Warm start issues...

[stuka1166]

Hello all...New MOPAR owner here.

Just picked up a 68' Road Runner/383/Auto...Cold start fires up. Warm start takes some pedal pumping to make it fire up...Common issue ??

Could it be vapor lock ??

Car has an Edelbrock carb if that helps ??

Thanks !!!

 

[texas69bee]

I would guess vapor lock. The 440 has a vapor separator, the 383 didn't but I don't see the harm in putting one in. Also block the heat crossover.

 

[red 69 runner]

I used to have that problem,replaced the Edelbrock with a Holley.

 

[Dennis H]

Big Block characteristic. 1/2 in spacer will help if you have room. Get used to it and learn what best works on those restarts.

 

[747mopar]

Had the same issue with a Holley, I insulated the fuel line that runs next to the headers, installed a carb spacer and went to 93 octane (less prone to evaporating) and no more hard starts.

 

[SlinktRR]

Not vapor lock. Cold start with a functioning choke, one gas pump to the floor to set choke and a shot from the acc pump is enough. Sometimes on a hot restart with the edelbrock the mixture will be too rich from fuel pooling in the intake/cylinders and you will need to open the throttle to lean the mixture. You won't need more gas in there, just hold the throttle open halfway.. or to the floor if necessary instead of pumping the pedal, then turn the key.

You can improve this by leaning out the jetting for cruise and idle mixture using fatter metering rods for the main circuit. Just watch your plugs and dont go too lean...

 

[coloradodave]

Some good suggestions above. Usually hot start issues are related to the fuel percolating from heat soak and dumping into the motor. As was said, 1/2" carburetor spacer (phenolic or wood), insulate the fuel line if it runs next to headers and between the fuel pump and the carburetor, and check that the float levels are correct. Don't touch the throttle when hot starting, or, as above, slowly open the throttle part to fully open before cranking. Each car will react differently. See what works for yours. It's not the carburetor. It's the make-up of our PC fuel.

 

[stuka1166]

Thanks for the info guys !!! I'm learning a lot !!!

 

[plymouth67]

Just Google.....Edelbrock heat soak...and be prepared to read for hours. Common problem with Edelbrocks since the float bowls are in contact with the intake at all times. It heats the fuel up and the fuel expands to the point in over powers the needle and seat, then drips fuel in to the motor while its shut off basically flooding it...spacing it up will help but may not cure it. Holleys are a little better because the float bowls are not in direct contact with the intake.

 

[coloradodave]

Good points. That's why it's important to use a non-conducting spacer under the carburetor. Depending on hood clearance, even a 1/4" spacer will help. 1/2" is better. Holleys will benefit from this as well. It is curable with a little work.

 

[SlinktRR]

Just Google.....Edelbrock heat soak...and be prepared to read for hours. QUOTE]

Yes this is right. Lots of different ways to try and fix but if you are not A) flooding so bad that your engine stalls B) diluting your crankcase oil with too much gas or C) fuel fouling plugs...then you should be alright. If your engine tends to load up when cruising (let off the gas on the highway and RPM's dont drop), this is a usual symptom.

The good news is that we are getting into the fall driving season, and as the heat and humidity dies down soon you will be able to jump in your car and just turn the key and hear the BB mopar start right up hot. Most of the time.