1969 FJ40

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I put the old carb back on with screw adjusted. Having the same result. Engine will run with / while pouring fuel down the throat of the carb.
Sometime this weekend, I'm going to remove the fuel line from the carb inlet, crank engine and see if fuel pumps out of the main fuel line. I doubt the pump is bad. It looks brand spank'n new.

I don't want to go this way but, I did call Mosley Motors about the TBI kits, just in case.
 
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I don't have experience with FJ40's and their carbs, but I do on old Chevy's and Studebakers. From what you have described, it appears you have a vacuum leak that is requiring that you dump gobs of fuel in to make it run.

Is this a mechanical fuel pump? It is possible that the diaphragm can no longer hold a vacuum and suck fuel from the tank to the pump.

Do you have an inline fuel filter in the line? If it is between the pump and the tank, it's a problem (unless it is an electric fuel pump). On mechanical diaphragm fuel pumps, the filter must be between the pump and the carb.

Check your hoses between the pump and the tank. If the fuel hose has any holes or cracks, the pump cannot generate a vacuum to pull fuel from the tank to the pump.

So, yes, verify your pump is pumping fuel.
It SHOULD have a strong stream of fuel, not at high pressure, but at decent volume. (max 7 PSI)

If the pump works, then the next possibility is where the intake manifold attaches to the head. If the gaskets there are not sealed, then you MAY be having vacuum leaks there and you A/F ratio is not proper to keep it running unless you're dumping in gobs of fuel.

Look for detached vacuum lines, PCV hoses, bad intake manifold gaskets, and bad carb mount gaskets.

Also need to verify distributor timing as well.

Some of the classic car guys are doing small electric pumps (vane style) at the tank to pre-pressurize the old mechanical pump and to assist with reducing possibility of vapor lock. It is run in conjunction with the mechanical pump. Not MY preferred method but many do this to BandAid the system.
 
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Also, is there a vacuum advance port on the carb that is NOT manifold vacuum, only vacuum under acceleration port?

Also, have you verified with a vacuum pump that the vacuum advance is working inside the distributor?

Also check to make sure you have a VENTED gas cap on your tank (or just remove the cap while trying to run) because otherwise, it will vacuum lock and the pump cannot suck fuel.
 
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Going to give this a shot from my phone.
Is this a mechanical fuel pump?
Yes
It is possible that the diaphragm can no longer hold a vacuum and suck fuel from the tank to the pump.
I don't think that is the case. I had removed the carburetor originally, cleaned it up, put it back on and found fuel getting into the reservoir on the carb. I see the same thing now. I think the pump diaphragm is good to go.
I also realize this is a PITA to do from a cell phone.
I'll take a look at the rest of the comments, suggestions, etc. later.
Maybe while at work tomorrow.
 
Joined
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Messages
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Going to give this a shot from my phone.
Is this a mechanical fuel pump?
Yes
It is possible that the diaphragm can no longer hold a vacuum and suck fuel from the tank to the pump.
I don't think that is the case. I had removed the carburetor originally, cleaned it up, put it back on and found fuel getting into the reservoir on the carb. I see the same thing now. I think the pump diaphragm is good to go.
I also realize this is a PITA to do from a cell phone.
I'll take a look at the rest of the comments, suggestions, etc. later.
Maybe while at work tomorrow.
 
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When I reawakened my Studebaker, I had a hose by the fuel tank that was cracked enough to not leak fuel but enough to suck in air so I couldn't draw a vacuum on the tank.

I would just get a small puddling of fuel when I would crank, not enough to keep it running.

Then I had to find a pump that actually worked because there are so many bad aftermarket pumps for the old domestic iron that you need an OLD one, then rebuild it with new parts.

Also, don't run any ethanol fuel. It will give you fits!
 
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So please keep in mind a PO did a 2F Swap and I don't think think the carb is original to the 2F engine.

Do you have an inline fuel filter in the line?
Yes
If it is between the pump and the tank, it's a problem (unless it is an electric fuel pump). On mechanical diaphragm fuel pumps, the filter must be between the pump and the carb.
Filter is after the pump, and before the carb. Looks like a have a bunch of things to check.
Also, is there a vacuum advance port on the carb that is NOT manifold vacuum, only vacuum under acceleration port?
I don't know.
Also, have you verified with a vacuum pump that the vacuum advance is working inside the distributor?
I have not.
 

tornadoalleycruiser

SILVER Star
 
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i have test fired many a truck with a hose from the inlet of the fuel pump to a 2.5 gallon jug.
I have also blown air backwards from the pump to the tank to listen for bubbles.
 
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1) Remove the gas tank cap.
2) Unhook the fuel line from the carburetor. (Could be done at the pump or the back side of the fuel filter, anyplace after the pump. You may want to attach a piece of hose so you can direct the fuel into a bucket.)
3) Crank engine to determine if you are getting fuel from the pump. Should be a thick stream of fuel, constant or in large surges at first. If it is a dribble, it's either a vacuum leak of a fuel pump diaphragm issue, or an in-tank pickup issue.
 
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Verified I have fuel to the carb. I got this much from one 8 second run.

Going to reconnect the main line and give it another try.

IMG_20190608_140239186.jpg
 
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Engine is starting on its own without pouring fuel down its throat.
Still does not want to idle. Working with adjustment screws now. Things are much better than what they were
 
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Got my daughter out here to start the 40 while I was attempting to adjust the carburetor. After two or three attempts noticed an electrical arc happening at my starter.
40 still does not want to idle on its own.
 
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One thing I did was adjust the play or slack out of the throttle cable providing tension on the cable / carb. This did allow for idle thought I'd bet it isn't the correct way to make it idle.
Mr. Butler stopped by on his way home from KC. He stated that when he had a 2F, it was very cold natured. He had to use the choke for a while before it would idle well.
Before I can move forward with the Carb, I need to look into the starter. It stopped last night when I was trying to move the 40 into the garage.
 
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I did pull the starter and took it to the part store on the corner. They had tested it and it did fine. It also didn't spark or arc.
Took it back to the house and stuck it back into the 40. As you may have guessed, spark/arc happened.
I still can't tell where it is exactly coming from. I think it is from/between the solenoid to the starter?
 
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If you get it to idle even for a bit and can do it at night, in the dark, shut off the lights and look for an electrical show as wires short and arc as it runs.
 
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