M38 Running Problem

1950 - 1952, M38, questions, discussions, regarding anything related to the M38.
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sigo
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M38 Running Problem

Post by sigo » Tue Nov 20, 2018 7:23 pm

So, I’ve done quite a bit of reading about related issues, I’ve tried some things, but I cannot solve the problem. Perhaps the collective can assist.

BLUF: My M38 will not stay running. It starts and runs very smoothly, then sputters and dies after about five minutes. Does the same at idle or while driving, doesn’t seem to matter. Carb was rebuilt two years ago and ran great prior to this problem. I added fresh gas. I changed the fuel filter.

It’s odd that it starts and runs as always but dies shortly afterword. I’m at a loss...


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artificer
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Re: M38 Running Problem

Post by artificer » Tue Nov 20, 2018 11:05 pm

Never recommend guessing, but try the condenser, as most seem to have problems with these lately.
Bosch VW Bettle will fit & work fine v/s repro .
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

Joe Gopan
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Re: M38 Running Problem

Post by Joe Gopan » Wed Nov 21, 2018 2:50 am

Has your M-38 sat for a long time, perhaps your fuel has gone bad. E-10 can gum up fuel systems in vehicles that sit for a few months.No two brands of E-10 store the same.

If you are going to follow the suggestion and replace the condenser, you may as well install the one made for your distributor, the direct fit numbers replacing OEM are:

NAPA AL-869,
Guaranteed Parts is ALC 23, ALC-72, ALC 72S
Delco is A-202
Standard Blue Streak is AL 111X

Good luck.
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sigo
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Re: M38 Running Problem

Post by sigo » Wed Nov 21, 2018 5:20 pm

Thanks for the tips gents. I’ll try the condenser next.

I don’t use ethanol fuel for exactly those reasons. I always pay the extra money for non ethanol.

rgmutchler
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Re: M38 Running Problem

Post by rgmutchler » Thu Nov 22, 2018 7:40 pm

Are sure that your gas tank is vented. Check the cap. Is the vent clogged or if it has a valve is it open. Run the jeep with the gas cap loose and see if it solves your problem.
RGMutchler
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artificer
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Re: M38 Running Problem

Post by artificer » Thu Nov 22, 2018 10:49 pm

Very good suggestion!
Especially with the timing of the happening/event.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.


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