77 vette with a mild cam, 650 carb, just installed a mallory hei 8548201c. set dwell at 13.
problem-starts when cold heats up turn off and will not start.with the old oem distributor it strarted hot or cold. I replaced with mallory because tack pick up did not work. engine is bored 30 over runing 3" pipes with flowmasters. thanks
350 CI REBUILT NEW AND BORED .030" OVER
• NEW PISTONS, CAM, HOOKER CERAMIC COATED HEADERS
• HIGH RISE ALUMINUM INTAKE MANIFOLD
• HOLLY 650 FOUR BARREL CARB
• CUSTOM 3" STAINLESS STEEL DUAL EXHAUST
• DUAL CHAMBER FLOWMASTER MUFFLERS
• 4-SPEED BORG WARNER TRANSMISSION
• T-TOPS
• NEW COOPER COBRA WIDE TRACK TIRES
• CRAGER MAG WHEELS
• LUGGAGE RACK WITH T-TOP QUICK CHANGE CARRIERS
• T-TOP LEATHER HOLDERS
• CUSTOM CAR COVER
• ORIGINAL PAINT (SILVER WITH BLACK LEATHER INTERIOR
• 73,000 ORIGINAL MILES 2,000 MILES ON ENGINE

 

Sounds like "starter soak". Starter or solenoid getting hot. How close are those headers or 3" pipes to the starter?

 

about 3" but did not have this issue with oem hei.

 

engine running 193-200 degrees after start up, never had a problem with oem distributor

 

Need more info. Define won't start a bit more. Does the starter behave differently or does it spin fine just engine wont start? Has the outside temp changed much since the conversion and how do you feel about a 180 tstat?

A few things come to mind. Since the only thing you changed was the distributor, could the timing be different than before? Perhaps try to retard the timing a touch and see if that helps. Too much advance can make it hard to start.

Heat soak will make the starter drag and really labor to turn.

Vapor lock, the starter turns fine but no fuel at carb.

Heat can also make the fuel boil in the carb and it will boil over through the accelerator pump nozzles and flood the motor

 

Your headers are probably giving off more heat than the old cast iron. Stock also had a starter shield in place. Did you reinstall yours?

 

when the car is running and at operating temp,does it break up at higher rpm above 3500?you could have just got a bad ignition module in your new distributor,i happens far and few between but it does happen.when they get hot they start to break down,any locale parts store should be able to test the module for you,jst ask them to test it about 5 or 6 times to make sure it gets to an operating temp because even a bad module will sometimes test good when cold

 

A little heat shielding between the header and starter certainly can't hurt, but could be you're running to much initial timing too. You can try backing down intitial timing 5 degrees or so, to see if this gets you moving in the right direction. Also, even though a hot engine, floor the pedal quickly for a carb enrichment shot. This will mess up the fuel/air mixture for a bit, preventing firing for a few cranks, and maybe help get the starter spinning. Some MSD and other ignition systems, actually retard initial timing during starts.

 

thanks for your help. here is more info;
timing is set at 13 do i go lower?
no heat sheild installed, will do so.
using origanal corvette from 1977.
will try 180* thermo.
when engine is up to temp i shut down and start engine with no problem but if i shut down and wait for 10 min or so the starter spins the engine but it will not start. should i reenstall the heat sheild between the carb and intake? I use a after market air clealer should i use something else. how would get cool air to carb?

 

using dwell of 13 should I go to 10?

 

Its not starter heat soak. Did the problem start when the heat shield was removed? I am going to guess fuel is percolating in the carb after you shut down. Next time you get it hot and get home , turn it off and remove the air cleaner and see if fuel is dripping down the throat. If you hold the gas all the way will it start? (Flooded)

What carb is it? Check for fuel dripping and reinstal the heat shield.

 

I'm thinking the other way, Vapor Lock.

Set it up so the problem happens, wait the 10 minutes.
Pull the air cleaner right a way and see if you have vapor coming
out of the throat of the Carb.
If you do then the float valve is leaking and your engine is flooded.

My guess is that there are no vapors.
If not then prime the Carb, and try to start the engine.

There are several ways to prevent Vapor Lock.
Install a section of "Rubber" fuel line in your all steel line to the Carb.
Insulate the steel line by the headers.
Electric fuel pump next to the fuel tank

Keep us posted

Ralph

 

Are you using the original carb? My '79 had a similar problem. I found out that the casting ports in carb were capped off with bronze and over time they will leak fuel back into engine after setting for a few minutes and causing it to flood. I removed carb and epoxyed the casting ports up and problem solved.

 

I have been having the same problem with my 73. Went out on a 15 min run and it burbled and stalled while at cruising speed. Managed to get off the road, pulled over and after about 30 seconds was able to start her back up and kept going for another 5 mins till I got to a buddies house. Left there 15 mins later and same thing happened on the way home, only this time when I got off the road it only cranked over a couple of times and then I got into a no crank/no start and was left sitting on the side of the road. Took an hour and a half and I had finally just called a flatbed to come and get me and then as soon as I got off the phone, I hit the key again and it cranked over and fired up just fine.....Pulling my hair out now as I can understand a percolating/vapour lock would cause it to die, but will a starter soak really make it no crank/no start for over an hour and a half. btw, there is no heatshield on my starter (has never had one on it in over 30 years). And the neutral switch seems fine, tried the shifter in all ranges and it still was a no crank/no start until it sat for the 1 1/2 hrs. I did have this no crank/no start occur last week when I put new metering block/fuel bowl gaskets, and acc. pump diaphragms on it...I had to crank it about 3 times at 10-15 second intervals until it refilled the fuel bowls and then it quit and I let it sit for about 5 mins and it went back to cranking normally. I think there is something very finicky or heat related with my recently rebuilt and installed starter.