Engine died!!No clue why!!
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Le Mans Master
Joined: Jan 2006
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Engine died!!No clue why!!
Car has been running fine but started acting up this morning. Started up fine but when it got warm it died and didn't want to start for ten minutes. Motor is a new 350/330 gmpp crate, with a new Mallory HEI. I'm using a Carter fuel pump with the return so I don't think vapor lock?? Up until now everything has been fine. I adjusted the distrubutor to 10 degrees of advance which is what the paperwork for the motor called for. Could it just be the carb out of tune? Holley 600 vac. secondaries. A mystery to me. Please help!!!
Melting Slicks
Joined: May 1999
Posts: 2,897
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From: Moon Township PA
I am surprised no one kicked in with ideas here. Obviously, there are only three things needed for an engine to run - air, fuel, and spark. When the engine died, did it just quit as if shut off or did it slowly die and sputter as if fuel starved? If the engine died while running, I would check your spark, once you are certain you have fuel delivery to the carb. I have had coil issues in non-Corvettes that only failed to work when the engine was warm. I swapped in a known good coil and was able to show that it was the problem.
Thread Starter
Le Mans Master
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Originally Posted by GaryS
I am surprised no one kicked in with ideas here. Obviously, there are only three things needed for an engine to run - air, fuel, and spark. When the engine died, did it just quit as if shut off or did it slowly die and sputter as if fuel starved? If the engine died while running, I would check your spark, once you are certain you have fuel delivery to the carb. I have had coil issues in non-Corvettes that only failed to work when the engine was warm. I swapped in a known good coil and was able to show that it was the problem.
Drifting
Joined: Jul 1999
Posts: 1,542
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From: Plano TX
A know the GM HEI module can fail and when it does it doesn't appear until the car gets hot. However it will usually run but when the throttle is applied the car will hestitae/bog since the ignition doesn't have enough energy to fire the misture as RPM's/cylinder presure rise. Could it be the module fails completely when hot?
I've also had the GM HEI pickup coil fail (coil at base of distributor that puts up pulse for reluctor ring). This however just failed and would not run at all.
Your problem sounds like ignition but seems to have different faults than I've encountered.
Could it be that it is running out of fuel after a period of time and it just seems to be at the time it gets hot? When it acts up can you hit the accellerator and see fuel squirt from the accellerator pump?
I've also had the GM HEI pickup coil fail (coil at base of distributor that puts up pulse for reluctor ring). This however just failed and would not run at all.
Your problem sounds like ignition but seems to have different faults than I've encountered.
Could it be that it is running out of fuel after a period of time and it just seems to be at the time it gets hot? When it acts up can you hit the accellerator and see fuel squirt from the accellerator pump?
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Le Mans Master
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Dave, this whole thing has me stumped. Gas is coming through the squirters no problem. I've put a plug on a wire and it has spark. I pulled a plug and checked it and it looked perfect. But when I go to start the car at this point..nothing. I've twisted the distributor every which way but Sunday and it won't hit a lick. Not even a backfire. Hopefully the distributor has not gone bad, cause it is brand new. But if that was the case I shouldn't be getting fire at the plug. If nothing else I would think it would run like crap or something. I've only had the car up and running three weeks since the motor swap and no real problems once I got the timing set.
Safety Car
Joined: Oct 2004
Posts: 3,725
Likes: 5
From: Minnesota
Not sure if it would have anything to do with your problem but I remember when I installed my 350 H.O. I had to change out the distributor gear to a "melonized" one. I think I got mine from GM Parts Direct. If you know you have fuel I think I'd pull the dist. out and maybe put the old HEI back in. I'm not a big fan of the aftermarket distributors anyway. Keep us posted.
Intermediate
Joined: Oct 2005
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Your problem sounds exactly like mine!!! I just rebuilt my motor, it would initially run but would pop and crackle out of the carb. Now it won't run at all. I have spark but it is intermittent. It definitely is not firing like it should. If you have the HEI style, you can take the ignition module out and take it to advance auto parts and then can bench test it. Had mine tested tonight and it was good. Put a lighter under it to heat it upp, because they can fail when heated, and it still passed. Check out my thread (Stumped!!!) It's totally crazy!! I can't get it to fire up for nothin'!!!
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Thread Starter
Le Mans Master
Joined: Jan 2006
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Originally Posted by Darthvetter05
Your problem sounds exactly like mine!!! I just rebuilt my motor, it would initially run but would pop and crackle out of the carb. Now it won't run at all. I have spark but it is intermittent. It definitely is not firing like it should. If you have the HEI style, you can take the ignition module out and take it to advance auto parts and then can bench test it. Had mine tested tonight and it was good. Put a lighter under it to heat it upp, because they can fail when heated, and it still passed. Check out my thread (Stumped!!!) It's totally crazy!! I can't get it to fire up for nothin'!!!
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
When some modules go bad they still produce a spark but the spark is weak. When under cylinder presure the mixture may not ignite.
See if the distributor uses a module similar to the stock GM and try a new one or better yet try to borrow one from a friend.
I always carry a spare module in my car.
See if the distributor uses a module similar to the stock GM and try a new one or better yet try to borrow one from a friend.
I always carry a spare module in my car.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by 69camfrk
Car has been running fine but started acting up this morning. Started up fine but when it got warm it died and didn't want to start for ten minutes. Motor is a new 350/330 gmpp crate, with a new Mallory HEI. I'm using a Carter fuel pump with the return so I don't think vapor lock?? Up until now everything has been fine. I adjusted the distrubutor to 10 degrees of advance which is what the paperwork for the motor called for. Could it just be the carb out of tune? Holley 600 vac. secondaries. A mystery to me. Please help!!!
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
I'm going to throw the old distributor back in at some point today. I'm thinking ignition too. If the dist. has failed, back to Summit it goes.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
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From: Eastern US XX
Originally Posted by Darthvetter05
Any luck throwing in the old dist? I am still not able to run either!! AUGH!!!
Intermediate
Joined: Oct 2005
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Supply voltage was bypassed by running a line from the battery directly to the distrib. Getting good voltage there. As far as grounding goes, that is a good idea. I can run a separate lead from the ground on the distrib to the chassis and see if that helps. I'll try that as soon as I get home!
Well wait.. scratch that. The negative terminal on the cap runs a wire to inside the distr. So, running a ground from the cap to the chassis will ground out the distr. and that would be bad. Hmmm...
Well wait.. scratch that. The negative terminal on the cap runs a wire to inside the distr. So, running a ground from the cap to the chassis will ground out the distr. and that would be bad. Hmmm...
Last edited by Darthvetter05; Oct 9, 2006 at 01:58 PM.
Thread Starter
Le Mans Master
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
I was going to throw the old distributor in today and see if there was a change, but after working on my friends Harley this morning we decided to go to the bar after it was fixed. Now it looks like a project for tomorrow morning. I work swings so plenty of time to work on it. As soon as I make the swap I'll report back. I hope it's not grounding out somewhere because that could be a real pain.
Intermediate
Joined: Oct 2005
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O.k. this makes no sense. I am out in the garage right now trying to trouble shoot. I took number 1 plug out and grounded it against the exhaust manifold. Crank it and no spark. While I was reaching to crank it again, I pulled the plug off of the manifold and cranked the car...Sparked like a demon!!! When I hold the plug away from manifold by about an inch, it will spark every time just like it should!! It will jump that 1 inch gap and spark perfectly. As soon as I touch it back to the manifold, it stops sparking. Tried to ground it to different things on the car and would not spark, but hold it away and it will jump the gap!!! So, something is grounding out in the car, but what?!?!?!
Thread Starter
Le Mans Master
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From: GA "When I grow up, I'm gonna get a Trans Am and run from the cops". Direct quote from my 4yo son.
Well, long story short....Mallory HEI out, Old HEI in, started up and ran fine. I was getting some spark with the Mallory but I suppose it was too weak to do anything. So, back to Summit goes the Mallory. I'm pretty disappointed in it, but also glad it wasn't anything more than that. I did not want to chase down a ground. Makes me wonder what kind of crap Mallory makes though!
Le Mans Master
Joined: Jan 2006
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From: Boca Raton Florida
Originally Posted by Darthvetter05
O.k. this makes no sense. I am out in the garage right now trying to trouble shoot. I took number 1 plug out and grounded it against the exhaust manifold. Crank it and no spark. While I was reaching to crank it again, I pulled the plug off of the manifold and cranked the car...Sparked like a demon!!! When I hold the plug away from manifold by about an inch, it will spark every time just like it should!! It will jump that 1 inch gap and spark perfectly. As soon as I touch it back to the manifold, it stops sparking. Tried to ground it to different things on the car and would not spark, but hold it away and it will jump the gap!!! So, something is grounding out in the car, but what?!?!?!
If you got enough spark to jump a 1" gap you should have enough to run. Verify timing, verify ballancer has not slipped, verify fuel.
Intermediate
Joined: Oct 2005
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Dump the Mallory and go with the MSD. Swear by it ..not at it!
Anyway.. I pulled all the plugs out and tested each one.. they were all bad!!! And these were brand new plugs!!! I had an old set on the bench and put this ein and they all worked perfectly. Had no time to try and crank it but I will tonight when I get home.
Anyway.. I pulled all the plugs out and tested each one.. they were all bad!!! And these were brand new plugs!!! I had an old set on the bench and put this ein and they all worked perfectly. Had no time to try and crank it but I will tonight when I get home.