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Well yesterday when I took my new to me M38A1 for a spin every thing worked great.

Today was a different story.

Around 5:30 pm I drove it 2 miles to a local gas station and added 3 gallons of gas. This is the first time I have put gas in the tank. I drove home and parked it no problems.

Around 7:00 pm I took my brother for a ride on some back roads, after about 5 miles it started to sputter and then die. We tried starting it but it would fire up for a second and then die.

I have some experience with small engines (lawn mowers, motorcycles) and it seemed like a fuel delivery issue.

I called a relative and they met up with me. Since it seemed like a fuel starvation issue I disconnected the aftermarket fuel filter that was connected between the fuel pump and the carburetor.

We drove home and I used a pressure washer to force a jet of water through the filter. After letting it run for about 30 seconds I cut the water off and shook the filter till it was dry.

We drove back the jeep and I put some sea foam in the gas tank just in case it was a water issue and then primed the carb with a little gas.

We put the filter back on and I held down the starter until gas came out of the fuel line and then we put it back onto the carb.

The jeep cranked up and I was able to drive it home about half way before it started doing it again. I managed to keep it running by holding in the clutch and pumping the gas pedal even though it was sputter and backfiring. Knowing I wasn't going to get any where I turned it off.

At this point we had to tow it home.

Its late, I am tired, but had fun.

Tomorrow I am going to go through the manuals to see if I can find out what happened.

These are my 3 leading theories -
1. Crude in gas tank was stirred up when I filled up and clogged fuel filter.
2. Vapor lock, I didn't try running it with the gas cap off. Could be that the gas tank vent line is clogged.
3. Crude in carburetor. It was rebuilt a month ago using a kit by the previous owner, but some crude could have gotten in there.

I am leaning towards theory 1 and 2.

I will drain the gas tank and float bowl tomorrow and replace the fuel filter.


Do you guys have any ideas?

Start at the beginning. If you suspect fuel contamination, take out the fuel tank and clean it out. The M38A1 fuel pickup in the tank has a fuel filter, examine it and clean it (if it's OK, you don't need the aftermarket filter). Check the fuel lines for contamination. If the fuel tank cap is the fording type, check that the vent is open. Then start looking at mechanical issues - is the fuel pump working - check it's output. Carb - rebuilt by the previous owner? - with the correct parts and assembled right? Could it be an ignition problem? You may have to go through a number of the Jeeps systems to find the cause. Good luck!

Well i replaced the fuel filter with a new clear one. You can see little particles in it and the gas is a little brown ish. The jeep runs again.

I took a flash light and looked in the tank and it has surface rust.

In the past I have fixed some really old motorcycle tanks using these kits

http://www.kbs-coatings.com/Auto-Fuel-T ... _p_34.html

and the result were great, no more rust problems. I did follow the instructions to the "T" though.

Any one sealed up there M38A1 tank?

I did. Before I bought my jeep, it had sit for 7 years without any fuel in the tank. Needless to say, it had rusted up in the fill neck and there was quite a bit of grit down in the tank. After a thorough cleaning, I used a gas tank sealer I found at Tractor Supply. Don't remember what it's called, but it's a blue goop. I let it set up for 24 hours and now she's as good as new.

I've had gas in the tank now for about a week and I've not encountered any leaks so far. Saved me $350.

Good luck with your fuel problems. I'm having the same difficulties with mine, except I'm getting too much fuel. Removed the carb and found the float was stuck in the full open position, and the check valve spring was missing.