76 Stingray Stalling After Heat Soak

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May 5, 2019 | 12:23 PM

Callin Cole Mote

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76 Stingray Stalling After Heat Soak

Here’s my issue. Just bought a super cheap 76 Stingray as a project, and on my 1strun about town, after about 30 minuets of driving the car started to cut out, was able to make home, but when I went to move into the garage would not start. Thinking it was an issue with an old and dirty Carb I tried some starter fluid but nothing. Next morning still nothing but with the help of some starter fluid got it running again. And then same thing, once the car was fully warmed up after about 30 minutes of driving cut out and would not start, this time didn’t make it home, left it on the side of the road, let it cool down, came back and with the help of some starter fluid got it running again.

Before I start stabbing in the dark, am I looking at a Vapor Lock issue? From what I’ve researched just the car cooling down should fix this issue. Is it Percolation? Any other suggestions?

May 5, 2019 | 01:27 PM

cv67

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From: altered state

St. Jude Donor '05

Check your coil and ign module when they get old they can give the same issues
Should cold start just fine

May 5, 2019 | 08:27 PM

4-vettes

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Could be a Coil, But the fact that you need starter fluid to restart makes me think it's a fuel problem. Have you tried undoing the fuel line at the carb to see if your pump is pumping? is your fuel return line hooked up and flowing?

May 6, 2019 | 06:00 AM

4corvettes

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From: Lancaster, Pa

I agree with both previous posters. I think you have multiple issues occurring simultaneously. Definitely get a new coil. Rebuild that carburetor or replace it if you have the $$$ right now. I believe your 76 has a solid state distributor so replace the ignition module inside it as well. Do these one at a time if you have patience. If you have more money than time, do it all at once. The fact that it won’t run when it is hot leads me to lean toward ignition. Because you need to spray starter fluid to get it running cold tells me that either you have a faulty choke or maybe your accelerator pump on the carburetor is not giving you enough gas to richen the mix for starting. Good luck!

May 6, 2019 | 06:46 AM

Rescue Rogers

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Multiple problems but you should give it a full tune first. I would go with new plugs, wires, cap rotor and coil. You dont know what the PO did or didnt do to maintain your new baby. And do and oil change and make sure you use an oil high in zddp/ zinc/ phosphates. Basics first. This should be done to every used car

Once you do that it should be fine except for the sstarts. That sounds like mine and it was fuel percolation due to the high alcohol content of modern gasoline. If thats the case a phenolic spacer will help alot along with a carb rebuild because the new fuel will eat old rubber.

what kind of carb do you have?
have you done any maintenace yet?
post pics, they help us alot

good luck, Scott

Last edited by Rescue Rogers; May 6, 2019 at 10:42 AM.

May 6, 2019 | 09:08 AM

HeadsU.P.

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From: Cool Northern Michigan

Failed coils and "modges" are the result of excessive heat. The modge has internal contact points making a circuit complete. With heat the contacts separate and all IGN is lost. No, sputters, no backfires, no loss of power, just dead circuit. Just like someone turned off the key. Once the modge cools the circuit is complete again.

It has been a common issue since '76 and one solution was a heat sink compound applied to the bottom of the module.
The fact that you still had a No-Start issue the next morning (cooled) suggest the modge is not the culprit here, rare but maybe.

You don't need to throw a bunch of parts in there just to see if one fixes the problem. However, just for peace of mind, a new module w/ compound applied will keep things up graded in the future.

Next issue and a cheap fix would be the carb filter. I suspect it barely flows and restricts even more with vapor-lock.

And last, make sure someone hasn't run the fuel line from the pump to the carb right up next to the cyl head. I have seen some that actually touch the hot iron.

Last edited by HeadsU.P.; May 6, 2019 at 09:10 AM.

May 7, 2019 | 08:37 PM

mdeslyper

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My 76 did the same thing. Like clockwork after about 30min would stop running. Root cause was ign module - easy to replace. Never bothered me again.

Mike

May 7, 2019 | 10:25 PM

drwet

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From: Thunder Bay

There's really very little to go wrong with the ignition system in these cars. I would replaced the module and possible the coil to eliminate these as a possibility. Do the cap and rotor at the same time just because they should probably be done anyway. Unlikely there could be enough wrong with the plugs or wires to cause the problems you are describing. Once you have done that, turn your attention to fuel delivery. In my opinion, that is most likely where your problem lies.