m-38 L-134 engine head gasket

[1948willyman]

Engine seems to be running fine with cold engine compression checking
at around 100psi. on all cylinders. Some anti-freeze seems to be seeping
out around one of the threaded studs and nut. Is this indicating that it is time for a new head gasket? I have snugged the bolt down some more but didn't help any. No oil and water seems to be mixing although some anti-freeze is getting gone I assume due to leaking by the head stud

[wesk]

You actually contradicted yourself by twice calling them studs and once calling them bolts.

I prefer studs because they make gasket and head installation easier. And they result in much less thread wear for the block.

Several of the head studs are open below into a water jacket and these are required to be sealed at their threads. This sealing with Form-a-gasket #1 by Permatex must be done each time the threads are disturbed.

I would suspect your head gasket is fine and you only need to remove that one stud and clean and re-seal it's threads.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[1948willyman]

Thanks for the reply. I will try that
I forgot to mention the black sooty spark plugs I found when doing the compression check. It has the waterproof type plugs in it. I guess the engine is running very rich
Any idea why so sooty looking even though running ok?
Also the spark plugs on all four cylinders look that way
Thanks

[wesk]

If they are sooty after an hour's drive then you are running too rich. If they are sooty after a few minutes around the yard then you haven't driven it long enough for them to get hot and clean themselves up.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[1948willyman]

Well I took the old boy out for a drive today and had to limp back home but I made it. I pulled the stud out , re-sealed the threads and torqued the nut back down on the head. Seems to have fixed the problem of leaking up around the stud. When out for a drive I noticed it had started spitting at idle a lot and the performance went down quite a bit. re-checked the plugs and found a lot of black dry soot on them once again. The motor seems to be sputtering a lot with quite dramatic performance drop. Tried a different set of plugs and wires and made no difference. Carb was rebuilt about two years ago but it sure seems as though something has went wrong inside it
No single cylinder seems to be causing the problem. Some black smoke is coming out the tailpipe as if it is trying to flood. What is your thoughts on taking the carb back off and looking into it again. It has the original waterproof carb on it. Just wondering if some of the internal parts has already went bad.

[hillbilly21]

WHAT ARE YOU RUNNING FOR GASOLINE IN YOUR JEEP ??
ANY ADDITIVES WITH THE FUEL OR JUST GAS ??

WAS ENGINE REBUILT IF SO DID THEY USE HARDENED SEATS ??

I DO BELIEVE YOUR CARB NEEDS A REBUILD

[wesk]

I'll ask the same question as above. What type gas is in it. If you park these jeeps for the winter with today's ethanol loaded gas then expect problems with rubber parts and plugged passageways.

You should run the jeep dry before storage. Then load up some Aviation 100LL gas (blue dye in it). Run the jeep for a short 15 or 20 minute drive and then park it for the winter.

The behavior you describe is often perforated, cracked or weather checked diaphragms in the metering rod and accelerator pump wells. Both can be removed and inspected/replaced without removing the carb.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[1948willyman]

I am sure it is the ethanol loaded gas with no additives added
The motor has not been re-built in years although it still runs great and does not smoke until now.
I will check on the carb. and hope to find something
Many Thanks

[1948willyman]

Well I checked on the carb and found that the metering rod diaphragm is pretty much toast and the accelerator diaphragm is not far behind
Any one out there that knows a good place to buy these parts again that might be of better quality?
I assume I will have to buy the whole carb kit again to get these pcs.
I cannot even remember where I bought this kit from two years ago when I was buying so many items to patch the jeep back up.
Surely someone has got these that is more resistant to the new gas on hand now???
Many thanks for all the help that has come from this forum over the years
I am sure a lot of time is devoted to this as I have used it time and time again. Could not have done this project without this. Again THANKS TO ALL

[wesk]

I believe you will find that MWM, AJP and Fitzpatrick G503 parts all have the kits with modern rubber products in them. I know of no one selling just the diaphragms. MWM/AJP sell the same kits and they are a one kit fits both 637S & 950S carbs. Fitzpatrick sells his kits a single kits for either carb.

Most likely the kit you installed was an 80's or older NOS kit from surplus stocks.

Try mixing your gas 1/2 to 1/2 Aviaition 100LL gas to pump auto-gas.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php