Carburetor running out of gas (1 Viewer)

[Rhinoliner]

I'm about to start pulling my hair out here and I need some help!

The engine starts perfect and runs perfect until it warms up (temp guage just past first bar). After that, it will continue to idle perfect as long as you let it, but if you rev it up to about 2K to 2.5K RPM the fuel level in the carb will quickly decrease until the engine dies.

Some background info:
1978 FJ45 with a 2F from Canada (no emissions stuff ever as far as I can tell)

Compression: 130, 130, 132, 132, 135, 137

Cam and lifters: brand new and valves adjusted properly (Hot)

Carburetor rebuilt by me using the Toyota manual and soaked in a Chem-Dip bucket overnight. (looks like new) Keyster? carburetor kit

Float level triple checked. Fuel at half glass at idle

Power valve jet .060 - plunger operates smoothly

Main jets (150 & 220) and (141 & 180 current) I've tried both sets and still have the same problem

Solenoid valve operates properly

Choke breaker operates properly

Only 2 vacuum lines on carb, choke breaker and distributor. Both checked and fine.

Intake manifold brake booster port capped and still the same problem.

Intake and exhaust manifold machined together and new Remflex gasket installed

New fuel pump. Same problem with original fuel pump.

Fuel tank professionally cleaned and lined. Fuel lines and filter are new

Intake manifold checked for cracks and none seen

Original exhaust flapper installed and operates freely

I've sprayed carburetor cleaner all over intake and carb while idling (warmed up) and there is no change in RPM


Does anyone have any ideas of what I am overlooking? This thing is killing me.

 

[Rhinoliner]

I just thought of one other thing. Vacuum at idle is 18.

 

[steverb]

mine did the same thing. it was driving me nuts because i thought it was a fuel problem. it turned out it was a bad cap and rotor. tune up fixed the problem.

 

[ducktapeguy]

Fuel input and return lines mixed up? The input line should be going into the one pointing torward the front, the return line should be coming from the banjo bolt near the valve cover. The banjo bolt will flow just enough fuel to keep it idling, but not enough for anthing above that.

 

[Rhinoliner]

mine did the same thing. it was driving me nuts because i thought it was a fuel problem. it turned out it was a bad cap and rotor. tune up fixed the problem.

I'm willing to try just about anything at this point. I'll have a new cap and rotor for it in the morning and give it a try. Thanks for the feedback.

 

[Rhinoliner]

Fuel input and return lines mixed up? The input line should be going into the one pointing torward the front, the return line should be coming from the banjo bolt near the valve cover. The banjo bolt will flow just enough fuel to keep it idling, but not enough for anthing above that.

Yeah, I thought about that a while back and verified them to be routed correctly.

The hard lines in the engine compartment on this truck can't get mixed up because the input line is threaded on both ends and the return isn't. But the hard lines under the truck could have been switched.

One thing I haven't checked is to see if the fuel tank outlet might be partially clogged with the lining material. Before I drain the tank and check that I was hoping someone might point out something that I am obviously overlooking.

Thanks

 

[igotta40]

Gas tank venting?

 

[Pin_Head]

What is the volume of fuel that the pump puts out in 15 seconds of cranking? It should be about 4-8 ounces. If not, something is probably obstructing the flow, like junk in the tank, a clogged fuel filter or fuel lines.

 

[Rhinoliner]

What is the volume of fuel that the pump puts out in 15 seconds of cranking? It should be about 4-8 ounces. If not, something is probably obstructing the flow, like junk in the tank, a clogged fuel filter or fuel lines.

I don't know the answer to that. I can check it tonight.

Thanks

 

[numby]

I would've thought distributor problems but you indicate that the fuel in the carb decreases at anything above idle. So it must be a fuel delivery problem. New cam rules out failed fuel pump cam lobe. Something is either blocked, clogged, or lines are switched as suggested above.