Vapor Lock Confirmation?

[81_El_Homewrecker]

it's either the pump or the lobe on the cam is worn

I’m sincerely asking, it’s possible for mechanical pumps to fail intermittently?

 

[pontiacgp]

what was the fuel pressure when the car started up?

 

[81_El_Homewrecker]

what was the fuel pressure when the car started up?

After cranking it built up to its normal 6-7

 

[pontiacgp]

After cranking it built up to its normal 6-7

I would try reving it up to see if it drops. I had a problem once that came out of no where when the GP died when I was accelerating on the highway. I was in my way to buy a new A/F wideband cause the one I had died so I was flying blind. It would idle fine and I could slowly get up to speed but I was on a busy highway. I had my spare carb so I installed that but same problem. The fuel pump was on it's way out so I limped it home and changed the pump.

 

[81_El_Homewrecker]

I would try reving it up to see if it drops. I had a problem once that came out of no where when the GP died when I was accelerating on the highway. I was in my way to buy a new A/F wideband cause the one I had died so I was flying blind. It would idle fine and I could slowly get up to speed but I was on a busy highway. I had my spare carb so I installed that but same problem. The fuel pump was on it's way out so I limped it home and changed the pump.

Good to know thank you! I revved it and it maintains pressure like normal. I’m thinking about replacing the pump if nothing else, just to rule that out as an issue.

 

[5spdCab]

I had a situation about 1 1/2 yrs ago that I suspected was vaporlock. After the 3rd episode in as many weeks, I added the insulated spacer between the manifold and the carburetor, rerouted the fuel line, and have not had any problem since. Also as added insurance, several weeks later I installed an electric fuel pump, including a pre-pump filter.

 

[fleming442]

Vapor lock is a bunch of hooey.

 

[pontiacgp]

Vapor lock is a bunch of hooey.

it is when traveling down the highway, the gas flow prevents vapor locks

 

[5spdCab]

it is when traveling down the highway, the gas flow prevents vapor locks

Right, it seems to only happen when you park the car, come back in 10-15 minutes to restart, make it out to about 1/4-1/2 block away, and stall in the middle lane when the float bowl goes empty..

 

[81_El_Homewrecker]

Wanted to update everyone.

I continued to drive without issue until it happened again. This time I unscrewed the gas cap thinking my newly installed vent may have been plugged causing a vacuum in the tank that eventually became too much for the pump to pull against. Well, needless to say it happened again a couple weeks later with the cap loose. Runs fine around town, but get on it at all or high RPM for a while it starts to drain the bowls and eventually die.

Double checked my supply lines at the tank and found I kinked the rubber line when putting the new tank in back in March. It must have flowed enough to keep the bowls full at low RPM, but any extended pulling it couldn’t keep up. What an idiot...

Thank you all for your help!