Engine mystery????

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   Also vinny i know for a fact that the points are opening and closing. I looked to see what the spark was like. at first it looked weak. then after testing the resistance loads of the primary and secondary ignition checked out i looked at at the spark again and seemed fine.. i could actually hear it "snap"

Im afraid the dizzy is grounding somewhere it shouldn't be. or its the timing chain. which i haven't looked at yet..  

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Rambo Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/27/2011 Location: Phoenix, AZ Status: Offline Points: 94	Post Options Post Reply Quote Rambo Report Post Thanks(0) Quote Reply Posted: Apr/18/2012 at 3:13pm
	Also vinny i know for a fact that the points are opening and closing. I looked to see what the spark was like. at first it looked weak. then after testing the resistance loads of the primary and secondary ignition checked out i looked at at the spark again and seemed fine.. i could actually hear it "snap" Im afraid the dizzy is grounding somewhere it shouldn't be. or its the timing chain. which i haven't looked at yet..

Thikstik Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Mar/20/2008 Location: Alabama Status: Offline Points: 1327	Post Options Post Reply Quote Thikstik Report Post Thanks(0) Quote Reply Posted: Apr/18/2012 at 3:33pm
	Do you know your dwell for sure? Also, the dizz shaft bushings could be worn out causing dwell to vary. Did u try as Farna said to crank while varying dizz ever so little both directions?
	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.

Rambo Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/27/2011 Location: Phoenix, AZ Status: Offline Points: 94	Post Options Post Reply Quote Rambo Report Post Thanks(0) Quote Reply Posted: Apr/19/2012 at 8:48pm
	yes i did try what farna said. still no dice. the bushings seem fine so i would think the dwell shouldn't vary. i just now pulled the dizzy again the check continuity from the condenser wire to the rest of the dizzy and all checked out fine. points open.. no continuity, points closed there was continuity. so now im checking the wiring.. the coil shows continuity across the + and - now what i don't know for sure and im going to look at the service manual right after i post this. but the wire coming in to the coil + shows continuity to ground and not power (12v on the batt.) with both the key on and the key off..

vinny Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/05/2012 Location: Calgary Status: Offline Points: 2837	Post Options Post Reply Quote vinny Report Post Thanks(0) Quote Reply Posted: Apr/19/2012 at 10:41pm
	The next logical step would be to run a jumper from the battery to the + on the coil and try starting. That would have to be temporary but should work for trouble shooting.

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19675	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Apr/20/2012 at 9:56am
	Disconnect the existing + wire before jumping!! Sounds like you found the problem though, the resistance wire has probably fried. Rather than cut the wire harness apart to find it (the resistance wire is usually around 2' or wire folded up and wrapped in the harness -- resistance is so many ohms per inch) you can just run a wire from the switch (I'd disconnect the existing wire from the switch just in case) through a ballast resistor to the coil. If you're running an electronic ignition you don't need the resistance wire or ballast resistor. Though a Pertronix Ignitor I and II will work with the ballast resistor (III requires a full 12V), they don't have to have it and will work fine off a full 12V all the time.
	Frank Swygert

Rambo Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/27/2011 Location: Phoenix, AZ Status: Offline Points: 94	Post Options Post Reply Quote Rambo Report Post Thanks(0) Quote Reply Posted: Apr/20/2012 at 11:58am
	Hum... That makes sense! Because even though my coil checks out to be okay. When I disconnect the condenser wire and jump the negative post on the coil to ground.. (imitating the points to see if the coil is throwing spark) its either super super weak or no spark at all.. I'll have to check that wire when I get home!

Rambo Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/27/2011 Location: Phoenix, AZ Status: Offline Points: 94	Post Options Post Reply Quote Rambo Report Post Thanks(0) Quote Reply Posted: Apr/23/2012 at 8:36pm
	well replaced the wire from ignition switch to the coil +. and still it just backfires up through the distributor. i thought maybe its the ign switch it self. so i just jumped the coil + to the battery. and still nothing. i replaced the coil it self even though it tested out just fine and still nothing. i checked to see if the plugs are actually sparking by rotating the dizzy with the back and forth and there is good spark. so i tested my spark plug wires to make sure the resistance was in check. two of them were a little goofy so i bought all new ones. still the same problem. im really thinking it the timing chain... so ill probably check that out here after summer. phoenix is already 100+ degrees and without AC thats a little to warm for my liking. i appreciate all your guys input! Thanks again!

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19675	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Apr/24/2012 at 9:16am
	Rotate it around until the TDC mark is at the pointer on the balancer. Pull the #1 spark plug and probe in with a screwdriver to see if the piston is at the top. If it's close but not at the top the timing chain has jumped. If it's not close at all rotate the crank one full revolution and check again. The balancer could be off, but more than likely it will be the timing chain due to the problems you're having. While you're doing this you can pull the dizzy cap and see where the rotor is pointing. If you're on compression stroke it should be pointing at/near #1 plug tower, 180 out should be opposite. Mark/note where #1 is before removing the cap. You can also try moving the distributor while cranking to see if that helps. If you set timing by the marks and the balancer has slipped you can have problems too.
	Frank Swygert

Thikstik Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Mar/20/2008 Location: Alabama Status: Offline Points: 1327	Post Options Post Reply Quote Thikstik Report Post Thanks(0) Quote Reply Posted: Apr/24/2012 at 2:37pm
	Farna, we think alike because i was gonna put the same thing about finding TDC and making sure piston was at top. But then I thought about it, TDC would still be ok and not be thrown off by tim chain. Im thinking of no real easy way to see if tim chain has jumped. Cylinder pressure that is unusual for your car (hopefully you know its norm) can tell the tale. It can go up or down with repeatability in all cyl with a jumped chain.
	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.

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19675	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Apr/24/2012 at 7:46pm
	But TDC along with the rotor position will tell if the timing chain has jumped! If you have it at TDC on compression stroke and the rotor isn't very near #1 sparker tower on the cap...
	Frank Swygert