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Jimreaves
12-26-2016, 08:14 PM
Hi Gentlemen,
My first post since rejoining the forum. I have 1955 M38A1 that sat up for a long time and the gas went bad in carburetor and would not crank. I took the carburetor off and had it cleaned and a carburetor kit installed. Cleaned out the fuel tank and put in fresh gas. It cranked up and ran good for awhile. Then it started shutting off after it ran for awhile like it was running out of gas. It has electric fuel pump so I replaced it as well but it still does the same thing. It will crank right up and run good but shortly will shut off like it ran out of fuel. Once the fuel pump runs for a minute it will crank right back up. Please advise what I should check next, possibly the float in the carburetor?

LarrBeard
12-28-2016, 09:11 AM
Disconnect the fuel line from the carburetor and let the electric pump run. Make sure it delivers a steady stream of fuel for a "long time". It is not unknown for trash to load up a fuel line. Fuel can ooze past it after things sit a while, but the pump can't pull enough fuel through the clog to let things run normally.

If you get plenty of fuel from the pump outlet, you may have a float sticking in the up position. Once the bowl empties, the float will drop and let the needle open. Just as the engine starts to splutter, there is always the old trick of whacking the carburetor with a stick to jar a stuck float loose .....

The science is finding just the right size stick....

Good Luck

Jimreaves
12-28-2016, 02:38 PM
Thank you sir. I actually determined that some trash had clogged up the ports in the intake of the carburetor. I blew it out with air hose and it cranked up and ran for a long time with no issues. Hopefully that trend continues.

Next question, it has always run extremely rich but seems worse than it did before since I had carburetor rebuilt. What is the appropriate setting on the fuel/air screw. I cant remember. Thanks for the help. I will have many more questions as I continue this project.

LarrBeard
12-29-2016, 03:52 PM
Thank you sir. I actually determined that some trash had clogged up the ports in the intake of the carburetor. I blew it out with air hose and it cranked up and ran for a long time with no issues. Hopefully that trend continues.

Next question, it has always run extremely rich but seems worse than it did before since I had carburetor rebuilt. What is the appropriate setting on the fuel/air screw. I cant remember. Thanks for the help. I will have many more questions as I continue this project.

The fuel/air screw sets the mixture at idle. Turn it all the way in, gently, and back it out 2 turns. That should let you start the vehicle. Adjust the screw for best idle.

The running mixture is set by the size of jets and metering rod in the carburetor body. I am not familiar with which carburetor you might have - I learned a lot more about the Carter YF trhan I ever wanted to know!

Jimreaves
12-29-2016, 06:57 PM
Thank you sir. More questions to come.