'66 Ambassador no spark again
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Category: The Garage
Forum Name: AMC V8 Engine Repair and Modifications
Forum Description: AMC-made V8 engine mechanical, ignition and fuel from basic repair to high-perf modifications
URL: https://theamcforum.com/forum/forum_posts.asp?TID=30175
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Topic: '66 Ambassador no spark again
Posted By: Trog
Subject: '66 Ambassador no spark again
Date Posted: Jun/13/2011 at 9:33pm
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Unable to search back to May 2009 when I first posted problem with '66 Ambassador V8 no spark wherein we discovered it was poor remanufacture of either the rotor or the cap (cannot find my notes either) wherein the gap was too large between the rotor and the cap contact. Well, we struggled with it and got the car running via new rotor or cap, but now again the no spark has hit us. I can get a instant spark each time I try to restart the engine but that's it and it's weak. Thinking maybe (as may have been suggested previously) of going to the Pertronix ignition but then looking through some of the postings on that subject do not appear to be all that encouraging with problems still persisting and then there's Ignitors I, II, III.....at this point not sure what to do. I did use local (national) parts suppliers for the rotor and cap, but as stated earlier had problems with manufacture of those and perhaps it has manifested itself again. Is there a particualr brand or source I should try to get for the cap/rotor or should I try to acquire a Petronix. I see Ignitor I on ebay for around $77. |
Replies:
Posted By: poormansMACHINE
Date Posted: Jun/13/2011 at 9:45pm
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What brand points/condenser are you using? Also, new or old coil? |
Posted By: Trog
Date Posted: Jun/13/2011 at 9:53pm
| NAPA or CarQuest for all ignition parts. I just cannot yet find my notes of exactly which was the problem previously, the rotor or the cap but I believe it was the rotor whose contact end point was visibly recessed too far to allow contact. Took us a while to find that after we had checked points, condensor, and coil. This is the third occassion of no spark on the car and we are talking less than a few hundred miles between times. The car is driven only occassionally like once a month or six weeks for short distances. |
Posted By: FuzzFace2
Date Posted: Jun/14/2011 at 10:11am
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Think I would start at the beginning again. New point/cond., rotor, cap, wires & plugs. There has to be a reason why the rotor & cap lugs got eaten up and it is resistance from plugs or wires. Now what gets me is “I can get a instant spark each time I try to restart the engine but that's it and it's weak.”? Are you getting a full 12 volts when cranking and do you get power to coil with key on? If not could be a bad IGN switch. If that checks out ok then as PMM said maybe a bad coil for the weak spark. What if you hot wire it will it start/run? Motor grounded to the body if not this may cause a weak spark because you do not have a full path. If you do go for the IGN kit after the parts you bought only thing not used would be the points/cond. I would go with new parts to get it running then replace with the kit. Dave ---- ------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: purple72Gremlin
Date Posted: Jun/14/2011 at 11:23am
| Check that little ground wire on the breaker plate? the coil??? Id sure take a look at it. getting 12 volts to the coil? another thing, was the cap and rotor the same brand? sometimes theres a mix match. I can remember years ago a cheapy points and condensor and a rotor kit would be $1.97................the better caps use copper terminals.....Accel, blue streak, mallory, and a few others I cant think of. |
Posted By: Trog
Date Posted: Jun/14/2011 at 6:34pm
| OK, all I could do this evening was check the coil. 12.5+ volts both sides but both sides drop to 8.2-8.5 volts when cranking. This car has a new coil with internal ballast resistor. I thought the voltage step down to 6 Volts on the car would not be until after ignition, the idea to prolong the lifr of the points. One time the car actually momentarily tried to start. (And for clarification, the first new rotor replaced was from NAPA and we found the rotor contact button on the brand new rotor to be too recessed to make contact with the cap. At the moment I do have a CQ rotor and a NAPA cap.) |
Posted By: Traveller
Date Posted: Jun/14/2011 at 6:38pm
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As an FYI, try a new condenser. There have been a large number of them that don't work right out of the box from the big name stores. My friend has an old 6 cylinder Chrysler and has been bitten by the condenser Gremlin several times. I know of several others with the same issue and we've duplicated it here. Seems like about 1/3 of the condensers we get aren't doing what they're supposed to. Crappy parts are laying around on shelves it seems.
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Posted By: poormansMACHINE
Date Posted: Jun/14/2011 at 6:42pm
Not much better in the 70's either. Probably the only spare part I kept in the glove box. |
Traveller wrote:Posted By: Trog
Date Posted: Jun/14/2011 at 6:53pm
| OK, guess that's the first thing I'll try, a new condensor. The worst part about this whole thing is that rear distributor cap screw jammed in up against the firewall that is barely accessible. I can usually get it loose but then getting it tightened back on is a real effort. I guess they are Delco intended for GM perhaps and adapted to AMC, but if the screws had been rotated 90 degrees it would make it so much easier. May be a few days before I can get to this. Thanks |
Posted By: bigbad69
Date Posted: Jun/14/2011 at 7:35pm
You didn't say anything about the plugs. If they got fouled for any reason, they won't fire even if cleaned. BTW, I found your old thread: http://theamcforum.com/forum/66-amc-ambassador-no-spark_topic9239.html - http://theamcforum.com/forum/66-amc-ambassador-no-spark_topic9239.html ------------- 69 Javelin SST BBO 390 T10 |
Posted By: FuzzFace2
Date Posted: Jun/14/2011 at 8:15pm
Also the rotor tip does NOT touch the posts in the cap. If so the tip of the rotor would break off. It should have a gap between rotor tip & cap post that the spark has to jump across, this adds to the resistance of the system the spark has to travell. Add to that bad wires & plugs with a large gaps and you can have issues.
Dave ---- ------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: Trog
Date Posted: Jun/14/2011 at 10:09pm
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Alright, the original thread. Checked plugs and they were not foulded but cleaned anyway. Thanks for the link to the original thread as it will help me know what all I did previously.
Understand about the rotor blade not touching the cap....it's just the rotor end contact point on the first new rotor we tried was indeed rececssed in visibly more than the original or the second one we acquired and we felt that gap was apparently too bog since until now that second CQ rotor has been working.
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Posted By: Trog
Date Posted: Jun/26/2011 at 6:17pm
| About to a dead end on this one what I can do. Changed out coil even though original one had 12V each side. Changed out rotor and condensor to new ones. Changed out coil to distributor cable. Still have just that instantaneous weak spark on the first ignition try but then nothing after that. |
Posted By: poormansMACHINE
Date Posted: Jun/26/2011 at 6:58pm
| Seeing 12 volts on the distributor side of the coil tells me the points are open |
Posted By: Trog
Date Posted: Jun/26/2011 at 7:32pm
| I checked while cranking with cap off and the points were opening and closing ok. |
Posted By: poormansMACHINE
Date Posted: Jun/26/2011 at 7:44pm
|
Did you ever change out the pigtail between the points and coil? The ground wire to the breaker plate? |
Posted By: Trog
Date Posted: Jun/26/2011 at 10:11pm
| I'll need to look at that. Believe that was done in '09 when we had the trouble then. But need to look agaon. |
Posted By: farna
Date Posted: Jun/27/2011 at 9:19am
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If it's a condensor/points problem the Ignitor will solve that. You want an Ignitor II. The original Ignitor will work fine, the II senses and adjusts dwell. The III has multi-spark technology (similar to an MSD box) and a built-in user settable rev limiter. You can use the III, but it's just over $140. II is $125-130, original is around $100. Not really a lot of difference in the prices considering what you get. The III is a good street/strip unit with the rev limiter. ------------- Frank Swygert |
Posted By: bigbad69
Date Posted: Jun/27/2011 at 11:34am
I have seen the wires break inside the insulator so everything looks OK, but in reality there is no connection. That was a "fun" problem to diagnose at -28C  ------------- 69 Javelin SST BBO 390 T10 |
Posted By: Trog
Date Posted: Jun/27/2011 at 8:02pm
| 0.22V at the coil - terminal and 0.1V at the inside-the-distributor side terminal. Ignition + side of coil reads ~ 9+ volts. Consistent reading over 3 measurements. |
Posted By: poormansMACHINE
Date Posted: Jun/27/2011 at 8:21pm
| Now start moving/pulling the power lead to the points and ground lead while you're checking it. |
Posted By: Trog
Date Posted: Jun/28/2011 at 8:40pm
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Continued testing. No effect on moving the new wires above.
First test I did was per '66 Service Manual page 17 "Primary Circuit Tests to detect excessive voltage drop. The measurement is supposed to be <0.4 Volt but I got 3.4 Volts on two occassions. Then I did this test:
1. Hooked up Voltmeter positive side to distriutor side coil wire.
2. Grounded other side of the voltmeter.
3. Turned the ignition switch on.
4. Points I know were closed so reading was 0 volt as it should be.
5. Cranked the engine and the voltmeter read close to battery voltage whereas I read on a tune-up chart that it should be 1/3-1/2 battery voltage.
With this reading, according to the tune-up chart results, there is an "open coil to distributor primary lead."
So it would appear the coil-to-distrubutor wire is bad?
Question: how is that wire replaced? Is there a rubber grommet or fitting through the base of the distrubutor? Since the wire has terminals on both ends, I'll have to deal with that.
|
Posted By: poormansMACHINE
Date Posted: Jun/28/2011 at 8:50pm
I asked about this wire and you said it was replaced around 09. How did you do it then? |
Posted By: Trog
Date Posted: Jun/28/2011 at 10:12pm
| I replaced the other two wires in the distributor, the condensor lead and the primary lead, the two that attach back-to-back. Did not touch the coil to distributor wire at the base. |
Posted By: poormansMACHINE
Date Posted: Jun/28/2011 at 10:25pm
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The wire should have the grommet molded on. If the wire moves, replace it.They eventually fall apart from flexing and corrode with age. |
Posted By: PHAT69AMX
Date Posted: Jun/29/2011 at 11:20pm
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Distributor Wire(s) Info - Delco Points Type
Ground Wire from Point Plate to Vac Adv Can Mtg Screw:
(2nd small hole in terminal at screw end locates on Vac Can Dimple)
#DL77 BWD is a "screw at both ends" replacement Point Plate Ground Wire. #DL77 BWD Distributor Ground Wire ( short internal Ground wire ) Wire from Coil to Distributor: #DL29 BWD Distributor Lead Wire - Qty. (1) $7.50 at Advanced 05-15-10 Tue 09-28-10 NAPA: Tue 09-28-10 Oriellys: Points Rubbing Block Grease: Tue 09-28-10 NAPA: Tue 09-28-10 Oriellys: -------------  Link to a http://www.youtube.com/watch?v=MySiKQsmWxU" rel="nofollow - Short YouTube Burnout Video |
Posted By: Trog
Date Posted: Jun/30/2011 at 6:22am
| Great information and have printed it out. Thanks very much! Try to get back to problem by this weekend. I pulled the coil-to-points wire a little through the grommet last night and got 12V at the points, so I'll try to see if I have spark now and then replace that wire as being the culprit. |
Posted By: PHAT69AMX
Date Posted: Jun/30/2011 at 9:49am
|
Welcome, copy and pasted, had it on my pc.
The Grommet at the dizzy is split on the Coil to Dizzy wires I've seen.
This allows remove/replace of the wire.
The wire itself has a small metal ring crimped onto it on the dizzy end that goes
inside the dizzy to prevent too much wire from coming through the grommet.
Old grommets can be pretty hardened, but usually come out in one piece.
Can cut the old wire first and remove from grommet.
This makes it easier to compress and remove the grommet. ------------- Link to a http://www.youtube.com/watch?v=MySiKQsmWxU" rel="nofollow - Short YouTube Burnout Video |
Posted By: poormansMACHINE
Date Posted: Jun/30/2011 at 3:12pm
Crap is all over 40 years old. Replace it all replace it once and be done with it. |
Posted By: Trog
Date Posted: Jun/30/2011 at 5:42pm
| Be this weekend before I'll get back to it if time permits. But after pulling that coil to points wire a little I thought I'd just see if anything changed and indeed I did get 12+V at the points terminal the whole time I tried to crank but again ONLY the initial spark and then never after that out of the coil wire. Strange but I'll replace the wire since I don't get the spark and see what happens. Pretty frustrating. |
Posted By: poormansMACHINE
Date Posted: Jun/30/2011 at 5:49pm
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So you had 12 volts at the points while you cranked and didn't see a spark? You shouldn't. |
Posted By: Trog
Date Posted: Jun/30/2011 at 7:25pm
| Right, with cap off and cranking the engine, I measured a constant battery voltage at the points/condensor terminal. Then held the coil cable ~ 1/4" from bare metal and only got the initial orange spark. Then immediately measured at the points terminal and it was still 12V. |
Posted By: poormansMACHINE
Date Posted: Jun/30/2011 at 7:32pm
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Open/intermittent circuit between points and ground. That's why I said just replace all the wires with fresh store boughts and take them out of the equation. Thge only thing simpler to fix than a points problem is a striker. |
Posted By: Trog
Date Posted: Jul/02/2011 at 10:03am
| Old wire removed and getting replacement tomorrow afternoon and then there will be all new components. But what about the neutral safety switch in the equation? |
Posted By: poormansMACHINE
Date Posted: Jul/02/2011 at 2:56pm
| If the starter turns what's wrong with the switch? |
Posted By: Trog
Date Posted: Jul/03/2011 at 7:49pm
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Had two problems, one yet to be solved.
1. Indeed the coil to points primary wire was faulty as with the new one I made up installed we got spark. So we buttoned it all up and got the car started for an instant, but then it would not keep running and we again los spark.
2. The terminal in the distributor for the points and condensor is retained by a copper spring but this spring is too weak to keep the terminals retained and thus they come off. Will replace this set of points with one that has a screw for tightening down and retaining the terminals. I saw the terminl jump off while cranking w/o the cap on.
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Posted By: 69 ambassador 390
Date Posted: Jul/03/2011 at 9:26pm
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Buy good parts. Stay away from the zone and others like it and hit a speed shop. The Accel and Mallory points are usually pretty good and try to stay away from Uni Points cause they force you to replace and adjust the whole thing when the Chineese condensor craps out. Also check the third or bypass wire on the solenoid if you have it. If there is a problem there it will spark at cranking but stop after you let off the key. Just jump a hot wire from the Batt. to the + side if the coil and it should stay running. If it does then forget about the distributor area or coil and look at the start bypass or ballast. ------------- Steve Brown Algonac, Mi. 69 Ambassador sst 390 84 Grand Wagoneer 69 Cougar XR7 65 Fairlaine 500XL 79 F-350 Super Camper Special |
Posted By: Trog
Date Posted: Jul/03/2011 at 10:01pm
| Yeah, online one of the national parts suppliers says "made in USA" but when I checked the boxes for thos every items across the counter, everyone of them said "made in China." On eof the other national parts dealer's are made in Mexico. Uni-points - is that the points/condensor combo? I have a set of those but haven't used them. Thanks for the tip about the third wire. My wife thought she detected "something" with the ignition switch when she was cranking the car over while I was under the hood. |
Posted By: poormansMACHINE
Date Posted: Jul/03/2011 at 10:31pm
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Yes, the uni point is the combo. Cross one bridge at a time. Swap the points and try it as it was intended with the key. |
Posted By: poormansMACHINE
Date Posted: Jul/03/2011 at 11:08pm
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This mfr always had good parts. Look up the numbers and search them out. http://www.wellsve.com/ecatalog.html - http://www.wellsve.com/ecatalog.html |
Posted By: Trog
Date Posted: Jul/04/2011 at 9:34am
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Thanks for the help guys. Another no go this morning so I'm letting the car sit for awhile. More important things to do than this frustration.
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Posted By: FuzzFace2
Date Posted: Jul/04/2011 at 10:05am
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I like the hot wire trick, wire from batt + side to coil + and see if it will run. If it does run then look from coil back to the key as it is not getting power. If it does NOT run then look from coil to dist. for issues. Right now it sounds like you dont know where to look?
I do here you about walking away, mine been sitting for over a month because it pissed me off.
Dave ---- ------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: Trog
Date Posted: Jul/04/2011 at 10:54am
| Tried the hot wire from battery to coil and no change. Replaced the wire from coil to points, got spark. Replaced everything. All the voltage and ohms readings are within specifications. Checked voltage from ignition switch to coil and 12+. Done all this stuff. In case it got flooded, I let it sit and cleaned all the plugs which weren't bad anyway....bene through all the motions. Burned out on it for now. There just aren't anymore places I know to look and check. |
Posted By: bigbad69
Date Posted: Jul/04/2011 at 11:26am
------------- 69 Javelin SST BBO 390 T10 |
Posted By: FuzzFace2
Date Posted: Jul/04/2011 at 11:42am
If you have somethiing else they will fit you can try them in it to see.
Dave ---- ------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: farna
Date Posted: Jul/04/2011 at 12:10pm
|
Once you find the problem do yourself a favor and stick a Pertronix unit in it (Ignitor or Ignitor II). Then you won't have points problems anymore. But unless you're POSITIVE the points are now the problem, fix it first. I'd try the hot-wire approach to see what happens next too (run +12V to coil). ------------- Frank Swygert |
Posted By: Trog
Date Posted: Jul/04/2011 at 12:49pm
|
Only the passenger side rear plug was damp at all and the rest were normal. I tried the hot wire from battery to coil + and there was still no change. Since yesterday we did get spark, albeit not blue but orange after replacing the coil to points wire, we thought we had the problem solved, i.e., until I noticed the "weak" spring retaining the points and condensor terminals. But I went back and looked again a time or two and they were still intact so it might have just been the terminal came loose the first time. It's peculiar that it will start just for a second but after that no restart. Then after messing around with it for awhile, you can just about repeat the happening. Plan is to go to Pertronix to eliminate points and condensor if I ever get this figured out. I have a '66 hardtop as well and have not experienced this problem with it and and Have had it a few years more. |
Posted By: farna
Date Posted: Jul/04/2011 at 6:49pm
|
Actually, the orange instead of blue spark indicates that the coil itself is likely bad. A weak spark won't run either -- may as well be no spark. Found that out with my 4.0L EFI engine when installing it. Was getting fire but it wouldn't run. Ended up being weak spark due to a corroded connector.
------------- Frank Swygert |
Posted By: gryzynx
Date Posted: Jul/04/2011 at 8:04pm
| Had a problem on a Chevy once. No spark, all looked well. found I had spark at the output of the coil, but not at the plugs. The rotor was arcing thru the center post to the distributor shaft. Did not see this until I removed the rotor. Since your 327 likely uses a Delco distributor, could be something similar. |
Posted By: Trog
Date Posted: Jul/04/2011 at 8:34pm
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We had a new rotor back in '09 when this no spark thing occurred....similar to what you had we had spark at the coil but not the distributor and it turned out that time to be a rotor contact buttojn too recessed apparently for the spark to jump across because a replacement rotor worked for a year until whatever this problem is.
Yes, the orange spark, the consistent orange spark bothered me but the coil is just a year old and all the ohms readings on the coil were per spec. But the coil is easy enough to change out one more time again so I'll do that soon and see what happens. I'm just burned out of lying on top of the engine changing out distrubutor components and doing all this testing with voltmeters and ohmeters that so far hasn't gained me anything.
|
Posted By: poormansMACHINE
Date Posted: Jul/04/2011 at 10:41pm
| Maybe it lost it's will to live! |
Posted By: 69 ambassador 390
Date Posted: Jul/04/2011 at 11:26pm
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Check the spark at the coil wire. That will eliminate the rotor and cap. If you have blue spark at the coil wire then it is the cap and rotor. To check the coil just disconnect the -NEG lead that goes to the distributor points and then with the ignition on ground and unground the Neg side of the coil. Still checking at the coil wire. Every time you pull the ground off you will get a hot blue spark. If not change the coil. Primary resistance checks only if a coil is definately bad. If the internal insulation is broken down then often the tiny voltage used in an ohm meter will not leak internally but several thousand volts will jump to ground. The same goes for secondary resistance. You can only check for a definitive bad but there is no way to check for a definitive good without a specialized coil tester that simulates actual working conditions. I am the only person I know who has one of these and it is very old. Now days the test is to get a known good part and try it. The problem is that a brand new part does not qualify as known good anymore. Find a good used one off a running car or test a new one before you install it. You can bench test a coil by supplying 12V to the + side with a wire and then grounding the Neg. side with a wire to the neg side of the batt. Use an old spark plug and the coil secondary wir. The plug body needs to also be grounded to the battery. When you break the ground to the coil it will produce a bright blue spark. Amaze your freinds by acting like a set of human breaker points. Shut the lights off and have your own little fourth of july. Just don't touch the coil wire or plug or you will deffibrilate yourself. ------------- Steve Brown Algonac, Mi. 69 Ambassador sst 390 84 Grand Wagoneer 69 Cougar XR7 65 Fairlaine 500XL 79 F-350 Super Camper Special |
Posted By: poormansMACHINE
Date Posted: Jul/04/2011 at 11:41pm
| I may have asked this question when I was 2 years younger, but how much resistance do you read between the negative post on the battery and the breaker plate? |
Posted By: 69 ambassador 390
Date Posted: Jul/05/2011 at 12:32am
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That is a great question. I had one give me fits and it turned out to be a badly grounded distributor. Lots of salt corrosion and a powder coated clamp. It took a couple of day to get the distributor out because of the white powder. cleaned the thing and sanded the clamp. instant blue spark. ------------- Steve Brown Algonac, Mi. 69 Ambassador sst 390 84 Grand Wagoneer 69 Cougar XR7 65 Fairlaine 500XL 79 F-350 Super Camper Special |
Posted By: Trog
Date Posted: Jul/05/2011 at 6:38am
| OK, I can try to do these tests tonight....but primarily the way I have been checking the coil spark is with cap off and rotor off. The ground to breaker plate was 0.1 V versus what I think I saw in a book should be <0.2 V. |
Posted By: JD
Date Posted: Jul/05/2011 at 5:49pm
LMAO  I think if this keeps on for much longer we all might lose our will to live.I know it would have been quicker to drive there and fix it.Sorry to be hard on you Trog but jeez.....  |
Posted By: Trog
Date Posted: Jul/05/2011 at 6:47pm
| OK, we'll just let this be my second to last posting on this subject since folks and me included burned out on it. Never had this much difficulty with a car's ignition system and this ain't the only old car I have going back even to 1941 including another '66 AMC and two mid 50s Nashes. It will go to a shop and see what happens from there. Tried above coil test (cap on and cap off) and got ONLY a weak initial spark and then that's it. Switched out coils and still got nothing albeit both coils are two years old but one never used. For the last time pulled the cap off and all is intact for wires and terminals. Ground for stationary point and baseplate tonight was 0 volts as opposed to what I have seen should be <0.02V (it was 0.01 last time I checked it). Maybe still another new coil....not gonna do it....it'll be up to whatever the shop finds and that will be the last posting. |
Posted By: jayson738
Date Posted: Jul/05/2011 at 6:53pm
Your dvom should be set to check ohms not volts when you check for continuity. You should have very little resistance to ground.
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Posted By: JD
Date Posted: Jul/05/2011 at 7:42pm
| Don't give up yet Trog, do what poormansMACHINE said about measuring the resistance....don't take my sarcasim to heart we all want to see you pull this through. |
Posted By: poormansMACHINE
Date Posted: Jul/05/2011 at 7:53pm
Volts? What happened to resistance as in ohms between the breaker plate and the battery negative post? |
Posted By: gryzynx
Date Posted: Jul/05/2011 at 8:10pm
| The volts check is legit, just have to make sure the points are closed, (current flowing) when you make the measurement. Looks like you are OK here according to what you have posted. |
Posted By: Trog
Date Posted: Jul/05/2011 at 8:10pm
| Ommeter read 0. Meter set to ohms, calibrated, one wire to negative battery post, one wire to clean breaker plate read 0. Checked it twice. Ommeter is in good working condition as I used it for the other resistance tests, all which passed according to specs. Distributor base ground confirmed as well as case as well as hold down bolt as well as battery cable to engine....all that. |
Posted By: JD
Date Posted: Jul/05/2011 at 8:29pm
| While you have the ohmmeter out check for continuity from neg. terminal of coil to breaker plate with points closed then crank to open points and check again. |
Posted By: Trog
Date Posted: Jul/05/2011 at 10:06pm
| Ignition coil with built-in bypass resistance, correct? No resistor on the firewall. Nothing shown on wiring diagram...only casual mention of a resistance wire. The two coils I have been using have the built-in resistance. |
Posted By: JD
Date Posted: Jul/05/2011 at 10:31pm
| Pretty sure you don't want a coil with a built in ballast resistance..... the ballast resistance is in the wiring harness ,the resistance wire they speak of,not in the coil! When you go to start and turn the key the resistance is by-passed and the full 12 volts is applied to the coil to give it an extra boost to help start the engine.After the engine starts and you release the key back to the run position the current now flows through the resistance wire to drop the voltage a bit so the points don't burn up as fast. |
Posted By: Trog
Date Posted: Jul/06/2011 at 6:38am
| Well, I do see advertised a Delco coil marked "use with primary resistance wire or external resistor" and maybe that's what I need although the other type with built-in resistor has "worked" for a couple years. The original coil had no markings on it and I cannot say how I got to using the coil we've had on the car for these two years. Not sure if this is the problem or not but it would sure be an easy fix. |
Posted By: JD
Date Posted: Jul/06/2011 at 5:04pm
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According to the Chiltons i have.... 1964 to 1971,i don't have a '66 amc tsm ,it says the ballast resistor is white porcelain located on the dash panel above and behind the engine on early models but late model engines are equipped with the ballast in the wire of the primary circuit and this wire replaces the dash mounted ballast resistor.Either way, your coil should not have an internal built in resistor in it if the Chilton Manual is correct.I think you need to get the delco that takes an external resistance that you spoke of. Do you have a AMC Technical Service Manual for your car ? Like others have said I think a new set of spark plugs would be a smart move too.
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Posted By: Trog
Date Posted: Jul/06/2011 at 5:59pm
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Well, since you guys are still hanging in there with me....yes I have the Service Manual which is where I noticed the sentence about the resistance wire which I was not familiar with. All I've seen are the porcelain or ceramic resistors mounted usually to the firewall. Local O'reillys did not have the AC Delco but do have a cross referenced Borg Warner which I would think would be ok and I will acquire it later this week when I'm in the neighborhood. Just unable to analyze if this could be the problem now based on previous starting and running of the car unless "somehow" something happened to render both virtually unused coils faulty. Wife checked American Parts Depot online catalog and found
only lists two coils...one is 48-55 and the second is 56-88 and says
All (w/External Resistor or Resistor Wire) Your advice I do have a new set of plugs and will change them out....even that awful access one at the left rear. |
Posted By: JD
Date Posted: Jul/06/2011 at 8:35pm
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Your losing quite a bit by having two ballast resistors inline ,one in the coil and the stock resistance wire too.The correct coil and new plugs will hopefully have her running like a top. |
Posted By: Trog
Date Posted: Jul/06/2011 at 9:58pm
| Keep you posted; hope to know by the end of the weekend. |
Posted By: Trog
Date Posted: Jul/10/2011 at 2:59pm
| No go. New plugs and new coil w/o internal resistor. Had orange spark only initially and then nothing. Repeated in a few seconds and same thing. Repeated after that and nothing at all. For this time, NO cap or rotor installed; only the coil wires connected to igniiton switch and points/condensor terminals. Coil cable held 1/4" from bare unpainted metal. Shop time. Can't keep going on and on with this, other projects more pressing. I'll post back here in the future if and when it gets figured out. I'm done testing. As the airlines always say "'preciate your patience." Note: Service manual wiring diagram shows a single yellow wire going from the coil + terminal to the ignition switch. This car has tan and green wires "molded together" going into the wiring harness and not appearing again. |
Posted By: FuzzFace2
Date Posted: Jul/10/2011 at 5:08pm
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1 last test seeing the TSM says 1 thing and you have something else and guessing you have been testing with the green/tan wires hooked up. Remove them from the coil + and run a jumper wire from the batt. + to the coil + Only other thing hooked to the coil should be a wire from the points to the - side and see if you have spark or run. Dave ----------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: Trog
Date Posted: Jul/10/2011 at 6:20pm
| SUCCESS! FINALLY! Thanks very much for suggesting this test again after parts were replaced. Got the car started with the jumper wire and it runs fine with the wire. This did not work previously with old coil with built-in resistor as I vaguely recall. Now to figure out what the problem is. In the interim I can hook up a switch for this function but I do not know IF the resistance is in line such that I have the 6-volts to the coil after ignition for driving. I just see nothing in the service manual wiring diagram or description detailing this "resistance wire." IF I can determine whether one of these tan or green wires leads to it (one has to be ignition), then it is obviously out of the equation now and then perhaps consideration to a "normal" ballast resistor on the firewall?. Again thanks. Such a relief to get the car started. Based upon what the problem really is, I may opt for the Petronix but thought I saw somewhere where the Ignitor I still uses 6-volts and I don't think I would need the Ignitor II or III features. |
Posted By: JD
Date Posted: Jul/10/2011 at 6:49pm
Yippee! You did it!! |
Posted By: FuzzFace2
Date Posted: Jul/10/2011 at 8:33pm
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Good to hear you got it running. When you said the bit about the wires I got thinking maybe they where shorting out and not letting power to the coil.
What color does the TSM give for the feed to the coil and does it say if resister or not?
The green & tan wires are they 2 wires with each having it's own end/connection or do both go to 1 end/connection?
If both wires have their own end/connection with key on do they both have power and what is the volts?
What happens when you crank the motor over same readings?
If you want an easy out just run a new wire from the IGN switch to the coil. You may need a resister so check into that if you run a new wire.
Good luck
Dave ---- ------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: farna
Date Posted: Jul/10/2011 at 8:52pm
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You said tan and green... but could that be brown and green? Does your car have a "Shift Command" transmission (console floor shift auto)? There is a green wire going to the neutral safety switch. Sounds like your car wiring has been tampered with. I checked the 66 and 67 TSM, just in case you had a late model 66 that may have had some wiring changes. There was no ballast resistor for 66 or 67. There was a blue and yellow wire connected to the coil (or spliced before they reached the coil, but most likely both connected to the coil post together). The blue goes to the starter solenoid, yellow through a resistance wire to the switch. 66 was the same way except the TSM states a PINK resistance wire instead of yellow -- no ballast resistor. The sixes didn't use a resistance wire, they used a coil with built-in resistance. That tan wire could be a faded pink wire? One of the wires should be traceable back to the starter solenoid. The other should go back to the ignition switch. The one to the ignition switch might be routed through the neutral safety switch. If you have a bad NSW you won't get power up to the coil. The 66 and 67 NSW are wired differently, but that shouldn't matter here. There should be four wires on the NSW. The two brown ones are for the backup lights. Pull the other two and connect together, then see if you have power to the coil with the switch on. The NSW might be bad... ------------- Frank Swygert |
Posted By: Trog
Date Posted: Jul/10/2011 at 9:22pm
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OK, the manual shows a yellow wire from ignition switch to coil + post and a blue wire from coil + post to the solenoid terminal "R". Previously I thought the manual showed one wire from the coil but that was applicable to the 6-cylinder only. The green and tan wires have one end connection.
Previously I measured 12+ volts at the + post terminal with the two-wires one-end connection terminal. At that time I had the coil with internal resistor and upon cranking, it would drop to between 8 and 9 volts as I recall.
Tan and green could be a very faded brown or pink and green. (On my hardtop they are both black and different gage).
Steering column gear shift.
I can try to check the other two wires out once I find the NSW which I believe is under the dash at the steering column.
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Posted By: FuzzFace2
Date Posted: Jul/10/2011 at 10:41pm
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Ok the TSM calls for yellow from key to coil & blue from coil to SOL. Over time with heat & oil I can see the colors changing to green (blue) and tan (yellow). You could open the harness to see if the colors are in fact B&Y and that the green (blue) goes back to the SOL. BTW the wire from SOL to coil is to supply full 12 volts when cranking for faster starting.
BTW2: for my 70 Javelin it shows the yellow wire from key to coil changing to pink (the resister part) in the center so if you look at either end you see yellow.
Dave ---- ------------- TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car |
Posted By: carnuck
Date Posted: Jul/11/2011 at 12:21am
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OK guys. Here's the scoop on points systems. They were designed for 6 volts. The ignition resistor system drops the voltage down to about 8 when running. Even the coils weren't designed for straight 12VDC except those with internal resistor. The fender mounted solenoid has 2 little wires on it. The S terminal is the one that gets power from the ignition switch when in the crank position. The I terminal is hooked to the + on the ignition coil and when you hit the key to start, it's energized with 12VDC from inside the solenoid (same contact ring that puts power from battery terminal to starter terminal makes contact with the I terminal) or whatever is in the battery at the time. (if the battery is slightly low, you may not get enough voltage at the coil to make enough spark to start) Yellow spark is bad condenser. ALWAYS! Blue spark is good spark. Having run many AMCs and Jeeps with points (as well as other brand vehicles), I suggest using a mid '70's Mopar electronic ignition coil replacement from parts stores. It has double the spark and doesn't tear up the points any faster than normal. Externally resistored Coils and points do NOT like 12VDC long term! They fry and burn out very quickly. |
Posted By: farna
Date Posted: Jul/11/2011 at 6:03am
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That's why I suggested a Pertronix unit AFTER the wiring issue is resolved. Trog, the Ignitor I is 12V for 12V cars, there is a 6V unit for 6V cars though. The II is the way to go, and it's only $20 more than the I. I forget the exact features, but I do recall looking them over. Yhe I is very basic and will do the job, the III has a rev limiter and would be better for a high performance/race application. The NSW is under the dash on the column -- you're correct there! Should be 6" or so back from the floor and on top of the column. ------------- Frank Swygert |
Posted By: PHAT69AMX
Date Posted: Jul/11/2011 at 10:34am
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Ignitor I & II use flying magnet, ring mounted under rotor, should shim dizzy for limited endplay.
Ignitor III is a prox switch tripped by dizzy shaft cam lobes, like Crane XRi,
checking / shimming dizzy not necessary. ------------- Link to a http://www.youtube.com/watch?v=MySiKQsmWxU" rel="nofollow - Short YouTube Burnout Video |
Posted By: Trog
Date Posted: Jul/11/2011 at 6:09pm
| Great information guys! I found the NSS under the dash easy access and should be able to get it all checked out by this weekend. And I see NSSws are availabe if I need a new one. |
Posted By: farna
Date Posted: Jul/12/2011 at 9:18am
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Easy test: connect the two wires together, bypassing the NSW. Remember, the brown wires are the back-up lights! Connect the other tow together.
------------- Frank Swygert |
Posted By: Trog
Date Posted: Jul/12/2011 at 5:51pm
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Closure! Fau;ty Neutral safety switch as I pulled the two green wires from the switch terminals, hooked them together with the ignition-to-coil wires back on and the car started and ran.
Thanks for all the help.
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Posted By: purple72Gremlin
Date Posted: Jul/12/2011 at 6:01pm
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Posted By: farna
Date Posted: Jul/12/2011 at 6:19pm
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The NSW is wired on those cars to prevent starting and running -- it interrupts power to the coil (switch-NSW-coil). When he bypassed the NSW with a hot wire directly to the coil it would start and run (that's what made me suggest the NSW). Maybe later models are wired differently? I know some in the mid to late 70s have an extra post on the solenoid that has to be grounded for the engine to start, and I think the NSW supplies the ground. ------------- Frank Swygert |
Posted By: 69 ambassador 390
Date Posted: Jul/12/2011 at 6:34pm
Thats why I asked about the third post on the back of the solenoid. I had one of those give me fits. I didn't know it went to the NSW though. Ya learn something every day. ------------- Steve Brown Algonac, Mi. 69 Ambassador sst 390 84 Grand Wagoneer 69 Cougar XR7 65 Fairlaine 500XL 79 F-350 Super Camper Special |
Posted By: purple72Gremlin
Date Posted: Jul/12/2011 at 6:36pm
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Posted By: Trog
Date Posted: Jul/12/2011 at 7:13pm
| Since this is a temporary hookup, I did not drive the car but just let it idle for a few monents. On a couple older cars from the 50s, the switch is totally bypassed and the only effect is it will start in drive or reverse as well.....no effect on running or driving. |
Posted By: farna
Date Posted: Jul/12/2011 at 7:54pm
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The whole purpose of the NSS is to prevent the car from starting unless in park or neutral. Older stick shift cars don't have one, just a back-up light switch. It wasn't until the later 70s that there were some cars equipped with clutch switches. Well, some older cars had such safety features before they were mandated by the government though. The push-button shift Ramblers, for instance. You turned the key switch to "run" but there was no start position. The Neutral button had to be pushed to start the car, so it could only be started in neutral. Park was via a separate lever under the dash with a cable to a separate arm on the trans. The car could be started in park, and one could start to drive off while it was still in park too! A few broken parking pawls... ------------- Frank Swygert |