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All running perfectly until repairs to fuel tank.

My M38 starts okay and runs well until motor warms up. Then runs rough.... especially on inclines. This has happened since my dad had the fuel tank out and the sender repaired so I could have a workable gauge.

Checked the fuel line to carby and saw minimal fuel come from hose which I thought was unusual. My electric pump and restrictor is okay & PSI output to carby is fine. Vent line from tank still attached.

Check of plugs reveal fuel may be running lean. No other repairs to tank other than repairing sender unit. Wondering if the volume of fuel from tank has been restricted somehow?

Col

A plugged vent system on the tank will cause your problem. The simple test is to remove the gas cap and drive the jeep. If the isuue goes away then the tank is not venting properly. You can eithe fix the problem with the vent tubing or the vent valve or take a close look at your cap. If it has a valve on the inside that has a fording position then turn it to the other position. If it has no valve it is an unvented cap and simply buying a vented cap will alleviate problem.




This is the vented cap. Leave it in the "Open" position. If you have an unvented cap then either fix the vent system at the tank vent valve or buy this cap.