1952 M38 Clutch Adjustment

1950 - 1952, M38, questions, discussions, regarding anything related to the M38.
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dero1548
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1952 M38 Clutch Adjustment

Post by dero1548 » Sat Apr 16, 2016 3:24 pm

Hello guys,

I just bought a 1952 M38 two days ago. It is awesome and a ton of fun! Now I have noticed that the clutch doesn't engage completely, and that there is about 2.5" inches of movement in the pedal before I feel the clutch begin to disengage. From what I have read that is supposed to be about 1.25 inches or so. I know its not totally disengaging as I will depress the clutch for about ten seconds or so first gear will still be rotating, but not at full force as I can manage to throw it into gear.

Where and how do I adjust the clutch?

Thanks,

Joe


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artificer
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Re: 1952 M38 Clutch Adjustment

Post by artificer » Sat Apr 16, 2016 3:44 pm

viewtopic.php?f=4&t=270021&p=1573036&hi ... t#p1572929
Doesn't matter which model this is how the Jeep clutch needs to be adjusted....it is always best to have the transmission cover off & watch exactly what the throwout bearing is doing & when it touches the pressure plate fingers.
This should correlate to approximately 1/2 - 3/4" movement @ the top of the pedal.
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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Re: 1952 M38 Clutch Adjustment

Post by Joe Gopan » Sat Apr 16, 2016 4:42 pm

You can feel the T.O. Bearing clearance by hand from underneath as you adjust the cable. It will show up as visible slack in the cable that you will be able to see and feel.
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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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Re: 1952 M38 Clutch Adjustment

Post by dero1548 » Mon Apr 18, 2016 12:48 pm

Thanks guys, I think I got it. Now the darn thing won't start UGH.

Appears to be fuel related. And the carb is getting great pressure, I am just getting no fuel. I am going to have the Carb rebuilt this thursday.

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Re: 1952 M38 Clutch Adjustment

Post by artificer » Mon Apr 18, 2016 1:24 pm

I am going to have the Carb rebuilt this thursday.
What for?
Will the vehicle start with a little drink?
Maybe the needle valve is stuck & not letting fuel into the bowl.
A bit of persuasion/hit around that area with a largish plastic screw driver handle might negate the need for a carburettor rebuild.
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: 1952 M38 Clutch Adjustment

Post by Joe Gopan » Mon Apr 18, 2016 2:56 pm

When was it last started? The YS-637S Carburetor used on M-38 do not take well to sitting for extended periods in excess of 1-2 years. The Diaphragms are prone to deterioration from contact with today's fuels which can affect starting and proper idle.
2011 MVPA PIONEER AWARD - MVPA #1064
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
LIFE MEMBER AM LEGION-40/8-DAV
7 MIL SPEC MAINTAINED MV'S
COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

dero1548
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Re: 1952 M38 Clutch Adjustment

Post by dero1548 » Mon Apr 18, 2016 3:26 pm

The darn thing will start easy enough on starting fluid but won't manage to keep running. I am sure the needle valve is stuck, it only has been sitting for a couple of days since i drove it last. I drove it about 100 miles right after I got it 4 days ago.

The real bummer is that I am so excited to drive it now that I have the clutch adjusted!!!!!!!!!!!

I'll try to give er a coupled of screwdriver whaps. I did it earlier and it didn't seem to make a difference.

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Re: 1952 M38 Clutch Adjustment

Post by dero1548 » Tue Apr 19, 2016 12:34 pm

Left the key on after attempting to start it, so now the battery was dead.

After a little charge I gave the Carb some hits with a rubber mallet. No success on starting. I decided to move further on fixing a couple of things, got new gaskets for the fuel sender and the pickup, and I also fixed the rear taillights, both of the covers were incorrect.

tapping the carb seemed to not make a difference. I have a hard time believing that it it worked fine so recently and now I have nothing... O well.


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