In need of M38A1 ignition/fuel system advise - Pirate4x4.Com : 4x4 and Off-Road Forum

jblogan · 07-06-2011, 01:57 PM

I have a '54 M38A1, converted to 12V, Solex 34 PBIC carb., original engine and trans. Last summer it was running fine, then one day it started coughing and choking while going down the road. Began working on it again this summer, changed gas, in-line gas filter, spark plugs, distributor cap, rotor, oil, and cleaned the carb. Nothing seems to have helped. I can start the jeep, but as soon as I give it some gas, it dies. Sometime it backfires. Smells like its running rich. New plugs are already black from carbon. I'm suspecting ignition system or fuel system. The carb seems to be getting plenty of fuel, but it may need rebuilt. Choke on carb seems like it needs adjusting. Funny thing is that this jeep only has maybe 1500 miles on a completely rebuilt engine and transmission. Any help is greatly appreciated.

Mike C2 · 07-06-2011, 05:27 PM

I have an A1 as well, mine is a '52. I swapped in a 6v distributor from a WWII jeep and used 12v coil. Mine also has a Solex and I have been pretty happy with how it runs. A Solex has no choke, but an enrichener circuit. This would be a good spot to check in that it could be stuck in the "on" position, also it could be that your needle and seat are sticking open causing it to run excessively rich but the weenie fuel pump can't supply enough fuel to drown it out. Anytime you have sudden fuel issues, a rebuild kit can't be a bad idea. Get a gallon can of Berryman's B9 Chem-dip and soak the carb and all the hard parts for a couple of hours. Clean it with spray carb cleaner and compressed air and re-assemble.

I got the Willys · 07-07-2011, 03:52 AM

On the ignition,the distributor condenser can cause those problems.Sometimes they fail completely and the engine won't run,and sometimes the engine runs poorly.And I found out,a new one is no guarantee of a good one.Any Chevy condenser will fit making it easier to find in the parts store.6 or 12 volt,all the same.For the coil if using a 6 volt system it should measure about 1.5 ohms between the two small terminals.12 volt needs bout 3-5 ohms total using a 3-4 ohm coil or a 1.5 ohm coil with a ballast resistor.The engine will run with the wrong coil but may run poorly ...And of course check the carb ..........

07-06-2011, 01:57 PM	#1 (permalink)
jblogan Registered User Join Date: Jul 2011 Member # 193945 Posts: 1	In need of M38A1 ignition/fuel system advice I have a '54 M38A1, converted to 12V, Solex 34 PBIC carb., original engine and trans. Last summer it was running fine, then one day it started coughing and choking while going down the road. Began working on it again this summer, changed gas, in-line gas filter, spark plugs, distributor cap, rotor, oil, and cleaned the carb. Nothing seems to have helped. I can start the jeep, but as soon as I give it some gas, it dies. Sometime it backfires. Smells like its running rich. New plugs are already black from carbon. I'm suspecting ignition system or fuel system. The carb seems to be getting plenty of fuel, but it may need rebuilt. Choke on carb seems like it needs adjusting. Funny thing is that this jeep only has maybe 1500 miles on a completely rebuilt engine and transmission. Any help is greatly appreciated. Last edited by jblogan; 07-06-2011 at 01:58 PM.

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07-06-2011, 05:27 PM	#2 (permalink)
Mike C2 Wheeler Join Date: Nov 2006 Member # 82950 Location: Austin, TX Posts: 228	I have an A1 as well, mine is a '52. I swapped in a 6v distributor from a WWII jeep and used 12v coil. Mine also has a Solex and I have been pretty happy with how it runs. A Solex has no choke, but an enrichener circuit. This would be a good spot to check in that it could be stuck in the "on" position, also it could be that your needle and seat are sticking open causing it to run excessively rich but the weenie fuel pump can't supply enough fuel to drown it out. Anytime you have sudden fuel issues, a rebuild kit can't be a bad idea. Get a gallon can of Berryman's B9 Chem-dip and soak the carb and all the hard parts for a couple of hours. Clean it with spray carb cleaner and compressed air and re-assemble.

07-07-2011, 03:52 AM	#3 (permalink)
I got the Willys Banned Join Date: Apr 2011 Member # 188016 Location: To be announced Posts: 85	On the ignition,the distributor condenser can cause those problems.Sometimes they fail completely and the engine won't run,and sometimes the engine runs poorly.And I found out,a new one is no guarantee of a good one.Any Chevy condenser will fit making it easier to find in the parts store.6 or 12 volt,all the same.For the coil if using a 6 volt system it should measure about 1.5 ohms between the two small terminals.12 volt needs bout 3-5 ohms total using a 3-4 ohm coil or a 1.5 ohm coil with a ballast resistor.The engine will run with the wrong coil but may run poorly ...And of course check the carb ..........