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I seem to be puzzled my 1953 m38a1 runs great for the first 10 mins . of driving ,then starts to miss real bad and run real rough as if it is not getting any gas. I think it may be getting hot ?. When it stops it will not start again for several hours. I put new plugs and gas filter on it and checked the wiring . It has me really puzzled, I need some good advise .Lake.

Classic symptom of a plugged gas tank vent. A quick and easy test is to remove the gas cap and drive the jeep. If the problem is gone then unplug the tank venting system. There are two lines on top of the tank. one is a vent. Find the end of this line on early A1's and wiith the gas cap OFF blow through the vent and make sure you can here air moving in the tank. If you have a later M38A1 without the fording vent line plumbing there will be a vent cap on top of the tank. Remove it and make sure air can flow into the tank. Also check your gas cap. There are two types, vented and selectable vented. The selectable vented has a center plate inside that has two positions: "CLOSED" for fording and "OPEN" for normal use. Make sure it is open.


Early A1 with vent line plumbing.


Late A1 with vented fitting.


Selectable type cap.

As you have probably surmised for the symptoms you have it means that both the on the tank vent and the cap must be plugged to cause your symptoms.

O.K Wes I will give fenting a try before maybe looing at the carb,thanks Lake