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Engine mystery????

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vinny View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Apr/08/2012 at 8:54am
I had a similar engine running rough problem in a 64 196 that was cured with a new condenser.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Apr/09/2012 at 8:49pm
I suggest doing the capacity test as suggested in the TSM. Then you can know, by measuring, if the fuel pump is delivering or not. Why guess? Hard tests are the way to go especially when things get weird.
1960 Rambler Super two-door wagon, OHV auto
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http://www.ramblerLore.com

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rambo Quote  Post ReplyReply Direct Link To This Post Posted: Apr/16/2012 at 9:40pm
similar issues... i have a 65 American with a 232. after finding a problem with the distributor gasket. i made a new one and it was running better than ever for about two days. the reason i figured it was the gasket was because i went to adjust the timing and once i had it perfect id go to tighten it down and it would mis run super rough and die. it had me scratching my head for a minute. up until the point where i pulled the distributor and noticed the gasket wasn't it good shape. so that i thought had fixed my rough running from time to time problem.

so after two and a half days it acts up again. it got progressively worse on that drive home. to the point where is dies a couple times and i barely make it home. once i get home it wont even start.  so at that point in time i think timing... so i pull the distributor again. check everything and it looks fine. this time i double check the timing by placing piston one at TDC and going through all of that. double check the TSM for proper firing order and rotor rotation. i also realize it has been about six months since the last major tune up. so i get a new cap, rotor, condenser, and plugs. spending less than 40 bucks i figure this shotgun effect will solve my issue. still nothing..

it cranks and cranks and cranks. but wont start. it just backfires up through the carburetor sometimes even catching it on fire.. i have noticed that while cranking the engine over if i pump the accelerator once or twice it kinda slows the cranking for a monent.. then will most likely backfire.  at this point i dont know what to do hence the reason im on here.

my next moves are to do a compression test. (head gasket?) pull the carb and go through all that. even though it was just rebuilt approx 8000 miles ago and make sure the jets and everything are fine. and maybe check the fuel pump flow..

i did try blocking off the wiper motor to see if that helped. it did nothing.

once thing i did notice after barely making it home that night after sitting for about an hour was when i pulled the distributor and looked into the crankcase it was filled with smoke..

please help!!! i want to enjoy this thing some more before summer hits!

Thanks in advance!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Apr/16/2012 at 10:39pm
Did you look at the wires going to dizzy..the primary wires that is.  The ones that feed the coil  and go into the dizzy and connect to the points? Could have insulation breaking down and grounding out inside dizz.  Also how about the b+ wire to the coil. And it could be the coil itself. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Apr/16/2012 at 10:44pm
Rambo.  I wouldnt start pulling parts other than ignition, because it really sounds ignition related.

Edited by Thikstik - Apr/16/2012 at 10:55pm
75 gremlin x, jeep 4.0 headed 258,
264H Cliff cam, intake,header. 390 holley. I want a 282 VAM motor!

AC/PS/PDB.

72 AMX , 304 2bbl, 3speed, now disks...probably will sell, want an automatic /AC.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Apr/17/2012 at 4:53pm
Backfiring does point to timing. Are you positive you have the engine on the compression stroke? Could be 180 degrees out now, which would cause back firing. You might just pull the cap and note where the rotor is pointing. Pull the distributor and point the rotor 180 degrees from where it was (exact opposite). Try cranking and see if that helps. If it doesn't help (or makes it worse) then reverse what you did. Doesn't matter where the rotor is pointing initially.

Have you tried moving the distributor one way then the other while cranking? You might just be a few teeth off.

Has the timing chain been changed? If it's a high mileage engine the chain may be a few teeth off. That will cause timing to be way off and backfires also.

Frank Swygert
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rambo Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2012 at 1:43am
okay i replaced the wire that goes from the coil - to the condenser. checked the primary and secondary ignition  resistance loads and everything is in spec. i tried flipping the dizzy 180. it didn't make anything better.

 i have been able to get it running. while cranking.. it backfires bucks and so on, then half rump runs. it order to have it somewhat idle the throttle needs to be approx 1/2 way down.. i keep hearing an occasional popping sound which seems to be coming from under the intake manifold towards the rear. (intake or exhaust manifold gasket?) at full throttle the engine might break 4000 rpms.. i dont have a tac..

also im not familiar with these older dizzy's. where is the dizzy suppose to ground and when? because im showing continuity from coil negative to anything that is metal on the distributor. is it suppose to be that way?

as for the timing chain... i dont think it has ever been changed. the milage shoe aprox 10,000 so id guess it has 110,000 on it. the car is in too good of shape to have 210,000 miles on it. all original glass, trim and door panels.. are the timing chain gears known to brake teeth? if so im afraid that might be the issue...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote kellysguy Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2012 at 6:39am
Originally posted by Rambo Rambo wrote:


also im not familiar with these older dizzy's. where is the dizzy suppose to ground and when? because im showing continuity from coil negative to anything that is metal on the distributor. is it suppose to be that way?

 
If the points are closed yes. I find it strange it started running bad when you tightened it down. A bad distributor gasket won't make it run bad. I'm wondering if somehow tightening it binds the distributor. Perhaps this somehow has lead to the drive on the dist to shear and become out of time.


Edited by kellysguy - Apr/18/2012 at 6:49am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote vinny Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2012 at 10:28am
Years ago I had a friend with a 304 in a Gremlin that was hard to start and took about ten seconds with foot to floor to get a few revs out of it. It hadn't had a tune up for so long that the points were no longer opening. Changing the cap, rotor, points and condenser as well as advancing the timing a whole lot really brought the engine to life.

What does the spark look like from the coil wire if you pull it out of the distributor cap and hold it close to ground  while cranking?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rambo Quote  Post ReplyReply Direct Link To This Post Posted: Apr/18/2012 at 3:07pm

i figured the reason the gasket was an issue was because it was grounding out once i fully tightened it down.. so once i made the new one all was well  for a couple days.

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