Info needed: Jeep not starting with new omix ada fuel pump

[Richard Whelan]

Was wondering if anyone knows if my problem with my new pump is with the spacer. It was needed for the old pump but is it required for the omix-ada fuel pump.

Thanks

[Jordan Baker]

Perhaps try taking the spacer off?

Did you bench test the new pump prior to install?

[rob love]

Do not take the spacer off, you could damage the camshaft or the pump.

Pull the pump and manually lift the lever.
I have seen where pumps will dry up and not pump. Getting some fuel in to them cures that problem.
But first I would do the following:

Are you sure everything is ok between the fuel tank and the pump? Add a bit of rubber line to the line at the carb and try and suck fuel up to the carb. If you get a mouthful of fuel, then the lines are OK. Then try and crank the engine to see if it expels fuel.

[Richard Whelan]

Hi

Thanks. The whole system is new but I checked and I blew air through all the lines from the tank. Pain in the backside but had to do it. I also filled the line from carb to the pump and turned the engine over and it pumped the gas out of the line.

The pump did draw some fuel but not very much. I did however prime the pump and the lines as best I could and am now charging my batteries for the next attempt

Just came to mind that if the spacer is not the problem could the problem be in the carb where the float is not working.

Richard

[rob love]

I have seen lots of cases where the needle gets stuck closed. That is usually tied in with using the crappy ethanol gasoline, which seems to cause the vitrol rubber on the needle valve to glue itself in place.



It only takes a minute to test the needle valve as it sits. Remove the line at the carb, and install a short piece of line in it's place. Blow into the line. If the needle is open you can blow into the carb bowl.



If it is stuck, a small tap on the needle valve area with anything may free it up....a screwdriver handle is good for that as it is less likely to harm the carb than say a 2 pound hammer. . If it's really stuck, it only takes a minute to undo the half dozen screws, remove the choke cable, and of course the fuel line and the vent line, and remove the top off the carb.



One concern on the Jeeps have always been the lack of a good fuel filter. The tank filter is rather coarse and allows rust particles thru the system, which get stuck in the needle valve and cause flooding. If you remove the top of the carb and notice what looks like very fine red sand, then you have the problem. Install an inline fuel filter somewhere along the fuel system.

[Lynn Eades]

Darcy Miller in Australia sells a paper filter to replace the brass disc element. I believe his range of Jeep parts are available via Mid West Military. A mechanical fuel pump can be bench tested with a vacuum / pressure gauge. from memory should draw (and hold) about 9 to 12 inches of mercury and deliver (dictated by the spring) something like 2.5 to 4 psi.
I hope that helps.

[Richard Whelan]

I will look into this paper filter Thanks

I have found two problems one was the pump and too solve it I did what Bob recommended and put fuel into the pump and it started working after about a minute.

The second was the needle in the carb. It was stuck. The jeep is now running. I need to find the float setting (trial and error)so that I can set up the carb.

Thanks for the help
Richard

[rob love]

Flip the bowl upside down and use a long 1/4" bolt across the top of the carb to set the float level. I believe that is without the gasket, but quite frankly even with the gasket it won't make much of a difference. I did not find these carbs to be too finicky.

And don't use ethanol.