Question on 65' 396 dying and restart

[Russell L.]

I have had 2 occurances where my car dies after having been driven up to operationg tempeture. This has always occured at an intersection. I when rpm's are low. I can't restart the engine and it just turns over and over until flooded or battery becomes low. After about 20-30 minutes it starts up with no problem. Is the voltage regulator or coil the issue or what?
Russ

[Wayne W.]

Re: Question on 65' 396 dying and restart

I have had 2 occurances where my car dies after having been driven up to operationg tempeture. This has always occured at an intersection. I when rpm's are low. I can't restart the engine and it just turns over and over until flooded or battery becomes low. After about 20-30 minutes it starts up with no problem. Is the voltage regulator or coil the issue or what?
Russ

Sounds like flooding to me.

[Tom H.]

Re: Question on 65' 396 dying and restart

Old fashoined vapor lock ???

[Joel T.]

Re: Question on 65' 396 dying and restart

I have had 2 occurances where my car dies after having been driven up to operationg tempeture. This has always occured at an intersection. I when rpm's are low. I can't restart the engine and it just turns over and over until flooded or battery becomes low. After about 20-30 minutes it starts up with no problem. Is the voltage regulator or coil the issue or what?
Russ

Russ;

I have a similar problem with my '65 396... Cold start and idle is not a problem. Warm idle is fine as well. However if I drive the car for a constant stretch and then come to a light, the idle will drop way down and she will almost stall... Seems to be heat related. Someone recently suggested opening the idle jets a bit more which I did, and that seems to help. Had the car out here yesterday in NJ, nice day low 80's outside. Happened to me once, but by the time I got home, she was fine... I will try cranking open the idle jets a bit more and give it a try.

Joel

[Russell L.]

Re: Question on 65' 396 dying and restart

Sounds like flooding to me.

Thanks for advice, car runs great up until it just dies at idle after warm. Won't restart which is very unusual for car then easily flooded after trying to restart with no success. Sits 20 minutes and starts fine. I guess I need to check electrical and other areas as well.

[Duke W.]

Re: Question on 65' 396 dying and restart

One of the problems with the L-78 is that the VAC is not properly matched to the engine's idle vacuum characteristics - same as the '63 L-76 - and this will cause idle instability.

The L-78 develops about 14" at 900, but the VAC requires 15-16" to pull to the limit, so idle timing is not steady, and this can destabilize the idle and cause the engine to stall. The '63 L-76 OE VAC was the same "201". It idles at 900@12", and I could not get a stable idle until I installed the '64 "236" VAC, which is pulled to the limit at 8" Hg.

This may not be the total solution to your problem, but replacing the OE "201" VAC with a B20/26 12" VAC should improve idle behavior.

According to other reports, the L-78 has full time vacuum advance, but check yours to be sure and convert if necessary.

Vapor formation at idle will exacerbate the problem, but you could also have a wiring harness or TI issue. Many cars have been known to have intermittent loss of ignition due to corrosion in the cowl harness connectors, and the TI also can have intermittent problems due to broken wires in the pickup coil or issues inside the amplifier.

Duke

[Jack H.]

Re: Question on 65' 396 dying and restart

My 396 would start and idle like a champ! No problems with it dying during a decel to curb idle maneuver.

I think I'd be looking in two places:

(1) Is this the factory original 3124 carb? If so is it warped? How's the 'plumbing' integrity to/through the GF-416 external fuel filter?

(2) All L78's were TI equipped. Check the integrity of ground wires, especially at the TI amplifier on the radiator support. Lose ground reference with a TI system and you lose spark RIGHT NOW!

[Domenic T.]

Re: Question on 65' 396 dying and restart

Russel,
Just a shot in the dark but I ran into that problem in the early 70's with "the quit after warm up", then starts after 20 min.
It was not on a vette but all 3 cars had the same problem, (high resistance connection). A connector in the plug got hot and expanded away from it's mate and killed the ignition. After about 20 min it would cool and make a connection again.
A poor connection in the connector (plug) can do it also. The 3 cars I found that had the problem were all new cars and the white connector was dark at the bad connection from the heat. Just a shot in the dark but another place to look. I found the first one by wiring a temporary light to the ignition and ran it in the car so the customer could tell me if the light went out when it quit. It did go out and I followed the wire back and found the problem.

DOM

[Russell L.]

Re: Question on 65' 396 dying and restart

Have original 3124 carb and new meter blocks etc. was rebuilt no problem with carb. I think this is electrical in nature will check T.I. area too.

[Rich G.]

Re: Question on 65' 396 dying and restart

I had the same symptoms with my 66 327/350 recently. Many good suggestions from the board and I tried them all. Then one day I saw gas coming out of the seam between the top and bottom of the fuel pump. Even I knew this was not good. Changed the fuel pump and the original problem went away. I think Jack, who is driving coast to coast now in his 66 had the same issue. He made it a couple of hundred miles from the first instance until the pump finally failed completely.

I guess if that was your problem, it would not flood, though. Not sure if it's easy to check fuel pump proper operation, but if it is it might be worth a shot, especially if this symptom just showed up with no other changes.

Rich

[Russell L.]

Re: Question on 65' 396 dying and restart

Thanks everyone for all the ideas. I guess that problems of this nature are so common that it is hard to find just one answer. But I will take all into consideration and proceed ahead.

[Raymond G.]

Re: Question on 65' 396 dying and restart

I have had 2 occurances where my car dies after having been driven up to operationg tempeture. This has always occured at an intersection. I when rpm's are low. I can't restart the engine and it just turns over and over until flooded or battery becomes low. After about 20-30 minutes it starts up with no problem. Is the voltage regulator or coil the issue or what?
Russ

Russell,
I think your problem may be vapor lock but, for what its worth, the TI coil can be a possible but rare problem. My 396 would run great until it warmed up. The problem was most noticeable when the weather was really hot. The car would quit running and would not start until it cooled off a bit. Happens that I had a hairline crack on the top of my 210 coil. Bummer! Now I'm looking for someone who can repair the crack.
Best, Raymond

[Timothy B.]

Re: Question on 65' 396 dying and restart

I would consider trying a new coil, I don't know if NAPA lists a replacement coil.

Also agree that the grounds on the wire harness need to be checked.