Slow to start - no gas

[tarriverarms]

Unless I just turned it off recently you need to pump the pedal and let turn over for a few seconds. It could take as much as half a minute or longer to get enough gas to start. I have already changed out the fuel pump thinking the diaphragm was leaking. Worse when it is warm or hot outside. Did it before and after carb change out.

Your thoughts?

[Mars]

Ethanol. Fuel evaporating out of your float bowl.
Someone else might know better but mine does the same thing.

Mike

[440sixpack]

What carb ?

[joe]

Is your choke circuit adjusted and working properly?

[tarriverarms]

What carb ?

Both the original 2bbl and the 4bbl quadrajet.

Is your choke circuit adjusted and working properly?

Don?t have the foggiest idea. Wouldn?t know how to check.

Figure there might be old dry rotted fuel lines.

[CutterN55]

As said above, it's likely the fuel evaporating. I had good luck and much better results will this same problem after installing a phenolic spacer under the carb. It keeps heat transfer to the carb down and after you shut her down seems to keep the fuel in the bowl a little longer. Also, make sure the little port on the fuel filter is at 12 o'clock.

[tgreese]

An open-element air cleaner will make evaporation much worse than the factory air cleaner.

The TSM has a pressure spec for the fuel pump. Easy enough to test. Good practice to replace all the rubber fuel hoses if you never have. They can be the source of engine fires, as well as leaking air.

[mwood65]

Common problem it seems

I had the same problem with my 1974 Cherokee 6 cylinder.


I Changed the fuel line from the tank all the way to the carburetor.
I changed the fuel pump thinking it was leaking since it has a check valve inside I was told to prevent fuel from flowing back to the tank.


I finally installed an electric fuel pump on the frame rail and wired to a toggle switch and just use that to prime the system.
( A wise old man who owns FSJ's and lives in Globe who's name I will withhold at this time showed me his set-up )


Just flip the switch for about 10 seconds and then turn it off, hit the key and it fires up no matter how long it sits.


Thanks "old man" in Globe!

[Chadryan]

Make sure the vapor return line on the fuel filter is on top of the line going to the carb (12 o'clock). I had this issue and realized that the fuel was draining out of the fuel filter through the return line since is wasn't above the main line.

[tarriverarms]

Make sure the vapor return line on the fuel filter is on top of the line going to the carb (12 o'clock). I had this issue and realized that the fuel was draining out of the fuel filter through the return line since is wasn't above the main line.

I hope I am this stupid, as this will be an easy fix!

[tarriverarms]

I finally installed an electric fuel pump on the frame rail and wired to a toggle switch and just use that to prime the system.
( A wise old man who owns FSJ's and lives in Globe who's name I will withhold at this time showed me his set-up )


Just flip the switch for about 10 seconds and then turn it off, hit the key and it fires up no matter how long it sits.


Thanks "old man" in Globe!

I considered using an electric pump. Wouldn’t the electric pump work the same way? Just turn on the power for a second and then hit the ignition.

[tgreese]

I considered using an electric pump. Wouldn’t the electric pump work the same way? Just turn on the power for a second and then hit the ignition.

Depends. You can get fancy with the electric fuel pump wiring.

The simplest is to connect it to a relay controlled by the ignition - then it runs whenever the key is on. This is considered less safe than some of the other arrangements, since fuel will continue to pump in case of roll-over, accident or whatever.

You can use an oil pressure switch to cut the fuel pump if the engine dies. Then you'll need the aux switch to prime the float bowl for starting. There are also control modules that run the pump a few seconds when you turn the switch, and shut off if the engine stalls. There are also switches that will shut off the pump in case of roll-over. Plenty of opportunities for fanciness.