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TR4/4A Vapor lock????

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I doubt that this is a fuel-pressure problem. Empty float bowls aren't caused by low pressure, but instead by low flow. Flow and pressure are two different (but related) things. The pressure regulator will reduce the pressure but affect flow only minimally. You have a fuel-delivery problem, either at the pump or somewhere in the line.
 
Yes, could be so, and after some further thought, I wouldn’t increase fuel pressure at this point. Instead, I’d run that engine while watching the gauge, and see what’s happening right when the engine stalls as you’re saying it does after a few minutes of operation. If the pressure goes way down before it stalls or spikes up before it stalls, that may tell you more about what is really happening. For now, though, I’d aim to keep your pressure at spec which is 1.5 to 2.5 psi, and anything greater may risk flooding or fire issues. I’d also check the wiring and connections to that pump, as well as the hose lengths, existence of kinks, type of hose, etc,
 
Sarastro said:
I doubt that this is a fuel-pressure problem. Empty float bowls aren't caused by low pressure, but instead by low flow. Flow and pressure are two different (but related) things. The pressure regulator will reduce the pressure but affect flow only minimally. You have a fuel-delivery problem, either at the pump or somewhere in the line.
Click to expand...
Thanks Sarastro for the info.
 
KVH said:
Yes, could be so, and after some further thought, I wouldn’t increase fuel pressure at this point. Instead, I’d run that engine while watching the gauge, and see what’s happening right when the engine stalls as you’re saying it does after a few minutes of operation. If the pressure goes way down before it stalls or spikes up before it stalls, that may tell you more about what is really happening. For now, though, I’d aim to keep your pressure at spec which is 1.5 to 2.5 psi, and anything greater may risk flooding or fire issues. I’d also check the wiring and connections to that pump, as well as the hose lengths, existence of kinks, type of hose, etc,
Click to expand...
Thanks KVH, I checked the pressure on the hose where it plugs into the carb. It was 3 psi. I turned the pressure up some at the regulator, didn't hook up gauge. Just took her for a short ride, didn't push it. Too hot outside to get stuck again!
Jim
 
It would be good to know what that pressure was after the car warmed up and was running for a while. I think I’d put a pressure gauge on the open side of that regulator.
 
KVH said:
It would be good to know what that pressure was after the car warmed up and was running for a while. I think I’d put a pressure gauge on the open side of that regulator.
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I will probably do that.
 
Not vapor lock, but sounds electrical to me. Do suspect the ELECTRICAL pump.
Most folks get a OTC at the corner store.Get a better one and regulate the pressure
to 3 Lbs or less.
Mad dog
 
Looking at all the posts, again at your pics, reading up on draw-thru superchargers—definitely more likely fuel supply and electrical pump issues as Steve and Mad Dog are saying. I wouldn’t focus on pressure if you’re at 3 psi.

See about that fuel pump and whether there were manufacturer recommendations on location and protection from heat. If not a high quality one, maybe start by replacing it, or at least run a flow test first to see what it’s putting out.

And I’d want to check the condition of the lines, and if possible the fuel tank. I’d check that the tank is venting properly from your gas cap.
 
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Here are two posts from a member with a supercharger and who had your exact problem and solved it:

“I have the regulator that came with the blower. Also it is the SU HS8 carb. 4.5 is the recamended pressure from Moss. I am getting 5 PSI right at the pump, but not under load. I think I will get a fuel pressure gauge to mount on the dash to keep a watch on things. I drove the TR to a show last night and had no problems. I will go for a longer and faster drive this morning.“

“Problem solved! The electric fuel pump was bad. I thought that a fuel pump works or don't, Talked to Blaine at Moss and thought it was rare for the pump to be intermittent . After installing the new pump I ran the TR down the HWY 4 bypass at 100 mph, for as long as I could stand it, (about a mile) No hesitation or any problems.
Thank You Randall for your help.“

Look up a 2015 post from “tinman58” and you’ll have the entire thread.

Maybe this:
Post in thread 'Electric fuel pump questions.'
> TR2/3/3A - Electric fuel pump questions. <
 
Thanks, you sure have been a lot of help. I wish you lived in TN and you could come help me figure it out in person.
Jimmy
 
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