Corn Hole?

[GregL]

I have been chasing a ghost in the machine, on and off for the last couple of years. I'm in the California desert so triple digits are common. Almost like a vapor lock problem, definitely temp related. I drive 20 minutes away, shut off, go into a store (or whatever) back out in ten minutes, restart drive 2 blocks, I start to run out of fuel. ONLY happens under these exact circumstances every time. Heat soak seems to bring it on. I can usually feather the throttle when it begins and it will keep running, after a mile it clears up (temp drops). Once in a while I cannot save it and it dies completely. Will not restart and depending on the ambient temp, it may take half an hour or over night. Check the carb when this happens, no fuel.
So OK, already replaced the fuel pump, filter, rebuilt the carb, all rubber hoses at tank and fuel pump. Nothing aftermarket, engine, exhaust, etc. are all stock. Feed line from pump to carb is clean and unbent, not touching anything. I've ruled out tank sock as I went to Vegas two weeks ago hauling a loaded car trailer, full throttle in passing gear much of the way with no supply/demand issues at all. (but the temps were lower). This week temps back up and it faded on me twice earlier in the week but managed to keep it going. Yesterday it faded and died. Half hour later, fired right up. I'm absolutely certain it is NOT ignition related.
After all this the only thing that is constant and that I've overlooked is the lousy California ethanol gas. I finally decided that is where my problem lies. Higher alcohol content, **** load of problems for older carburated vehicles here in the high temp areas especially. So today I picked up some Thermo-Tec wrap to wrap the fuel line from the pump to the carb. I'm pretty sure that's where my problem is. When it goes bad it runs just about as long as it takes to empty the carb bowl before dying.
So, ethanol made from corn, pumping it into my truck....does that make this the "CORN HOLE"?

You must be registered for see images attach

 

[CSFJ]

Not sure if it makes that the corn hole, but it sure does mean the consumer is getting corn holed.

 

[foamypirate]

You must be registered for see images attach

 

[smoothandlow84]

High ethanol blends in gas will deteriorate the ruuber seals and rings in your carb and fuel system. You may want to consider nitrile replacements. Ethanol makes the older seals brittle and prone to leaks.

 

[RustyPile]

It also plays havoc with the composition floats in the carburetors....

 

[HotRodPC]

Sure hope you don't get'cher pecker stuck in that corn hole. It might have a flapper that grabs a hold and don't let go.

 

[HotRodPC]

High ethanol blends in gas will deteriorate the ruuber seals and rings in your carb and fuel system. You may want to consider nitrile replacements. Ethanol makes the older seals brittle and prone to leaks.

I've seen some nasty corroded aluminum too inside carbs that obviously ran E-10 or higher. Real bad on aluminum thin walled lawn equipment.

 

[twinturbo427]

This exact problem plagued the 82-83 v8 f-bodies. The fuel line from tank to engine would heat soak and the change in line diameter caused a pressure drop yielding vapor lock. GM added an in-tank low pressure pump and it solved (band aid) the problem.

 

[1987 GMC Jimmy]

This exact problem plagued the 82-83 v8 f-bodies. The fuel line from tank to engine would heat soak and the change in line diameter caused a pressure drop yielding vapor lock. GM added an in-tank low pressure pump and it solved (band aid) the problem.

Interesting, the Chevy P-Van based Class A motorhomes also did this exact same thing in mid-1984 for the exact same reason.

 

[bucket]

I don't think it's a corn hole in this case. It's only a corn hole on cars that have it hidden in the rear, behind a license plate or something. In the old days before ethanol, it was just a gass hole.

 

[Jerry phillion]

I'm pretty sure gm made some mechanical HiPO fuel pumps,
With a fitting for a return gas line. Can't remember if for sb
Or bb. You will have to make provisions at your fuel tank
For a return line. This would help keep your fuel moving
And cooler. Also wrap your whole fuel line with the thermo
Tec wrap. You didn't mention what kind off carb you are running.
If this don't work , maybe a diff carb might.

 

[GregL]

Thanks Jerry, fuel pump has the return line already and carb is the orig. Rochester. Truck is very original from air cleaner to oil pan. Also stock exhaust, no headers.
I covered the top of the fuel pump with the Thermo-tec as well just in case heat radiating from the exhaust manifold is an issue. I don't think I'll need to cover the rest of the steel line along the frame as it's very far away from the exhaust system.