Engine Missing

1952 - 1968, M38A1, M170, questions, discussions, regarding anything related to the M38a1 series.
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Bill P
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Engine Missing

Post by Bill P » Sun Apr 19, 2015 6:49 am

Recently, after running fine forever, my engine started missing really bad. The engine will start right up and run perfect for about 3-5 minutes and then it will start missing. If you step on the accelerator, it sputters, misses, etc. I have checked the carburetor and the float seems to be o.k. Fuel is getting to the carburetor fine. I checked the air cleaner and found no problem there. I pulled the plugs, cleaned and re-gapped. I had to replace the coil about a year ago, along with the points, etc. Could that be the problem?


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Re: Engine Missing

Post by Joe Gopan » Sun Apr 19, 2015 7:49 am

Points are a good suspect. Also look inside your cap for carbon tracers adjacent the contacts, this happens with distributor cap age and sparks will jump. Do not tighten the Spark Plug Wires up tight with a wrench, just snug them, we used to do the nuts at the sparkplugs a bit more than finger tight. Too tight will roll over the tops of the plugs inwards, they can then grip the red rubber insulator and cause them to break when you remove the wire from the sparkplug.
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skyjeep50
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Re: Engine Missing

Post by skyjeep50 » Sun Apr 19, 2015 8:49 am

Check the coil resistances as well. My M38A1 would do the same thing especially on a warm day - sputtering, missing, poor acceleration. The coil was going bad. The replacement coil I got was a take-out, I haven't tried the foreign-made "shiny" coils that some posts have suggested don't last very long. I've seen US made coils in dealer inventories but haven't heard if they are reliable or not.

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Re: Engine Missing

Post by Joe Gopan » Sun Apr 19, 2015 8:55 am

Some new point installations require regapping sooner than others.
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HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
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Old Marine
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Re: Engine Missing

Post by Old Marine » Sun Oct 10, 2021 3:55 pm

I have the same problem and wonder how you might have solved the glitch? My suspicion now involves vacuum maybe coil but I have a relatively new distributor.

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Bill H.
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Re: Engine Missing

Post by Bill H. » Sun Oct 10, 2021 6:34 pm

Old Marine wrote:
Sun Oct 10, 2021 3:55 pm
I have the same problem and wonder how you might have solved the glitch? My suspicion now involves vacuum maybe coil but I have a relatively new distributor.
You realize this thread is over 6 years old???
Bill H.

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dpcd67
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Re: Engine Missing

Post by dpcd67 » Tue Oct 12, 2021 7:43 am

Yeah, I have an M38 that is missing it's engine too and I thought that posting onto a decade old thread that no one will ever read would be the best place to find it.
It's got to be out there somewhere.
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Wolfman
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Re: Engine Missing

Post by Wolfman » Wed Oct 13, 2021 12:17 pm

:roll: Is this where the canned laughter gets turned up ?
You guys crack me up ! :lol:
Old Marine just saved a lot of typing bringing up an old post with the same problem.
And now for an unpaid commercial break sponsored by G-503.

Does your old M-38 a1 start great and then start missing after 5 or 6 minutes ??
You checked the carb, spark plugs and points & condenser. They seem OK but it just keeps doing it ??
Lets see. OK for 5 or 6 minutes ??
Heat ??
When it cools down, does it do the same thing over again ??
??????????
Tight valves that need adjusted !
Now, back to the show.

You guys crack me up !! ?? I already said that. :D
Oh. I had an M-38 come in the shop that did the same thing. 8)
Stress is getting to us !
( Engine missing. I had the same first reaction, TJ. )
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dpcd67
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Re: Engine Missing

Post by dpcd67 » Wed Oct 13, 2021 7:46 pm

You do realize that you will never hear from him again........
Difference is, that I actually do have an M38 missing an engine. I mean, gone.
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