Camshaft bearing

1950 - 1952, M38, questions, discussions, regarding anything related to the M38.
Cannon Cocker
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Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 5:18 am

The front edge of the cam bearing is suppose to be chamfered according to the manual. Anyone know why? Willys L Head Engine Rebuild Manual states it's to "aid in inserting the camshaft". If this is the reason, does anyone know why or how it aids? I ask this question because I had the bearing installed by the machine shop along with other work performed. They did not chamfer the front edge. In attempting to load the camshaft, it goes in fine but stops short of complete installation by 1/4 inch. And yes, I have checked the block and cam journals for burrs and found none. Appreciate any advice offered.


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Re: Camshaft bearing

Post by Joe Gopan » Sat Sep 23, 2017 5:51 am

I install the current Cam Bearings with a small block of wood and a hammer. Staking is not necessary, and has not with the replacements since the late 40's.
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Re: Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 6:19 am

Thanks. I was hoping the lack of chamfering or staking as you call it was the reason why the camshaft is not loading all the way. (although I can't see why) The first time the machine shop installed the bearing, the camshaft lacked nearly an inch loading. On the second attempt I'm shy by 1/4 inch. Getting closer but no payday yet. This ain't my first rodeo for building engines but it is for the L134. Never had this problem before. Maybe I'll have the machine shop load the camshaft next time so they don't think it's me. Bet they'll want to do a line bore!

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Re: Camshaft bearing

Post by dpcd67 » Sat Sep 23, 2017 7:53 am

Be careful; the chamfer is not the reason it ain't going the last 1/4 inch. They should go in easily; may be a burr in your block on one of the inner bearing surfaces. (no bearings inside as you know). Check each bore with a finger. Insert your cam backwards into the front bearing and I am sure it will go in easily which will prove it isn't that. Is your back freeze plug in place? did permatex get onto the cam bearing surface of the block? Did your cam get warped in storage, did you store it vertically? They will move sometimes as will cranks.
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Re: Camshaft bearing

Post by dpcd67 » Sat Sep 23, 2017 7:56 am

Staking and chamfering are two different things. Neither of which is really necessary.
Oh, your machine shop should have checked your cam for straightness; mine always does. They are often not straight.
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Re: Camshaft bearing

Post by Joe Gopan » Sat Sep 23, 2017 9:36 am

I is your Cam Bearing USA sourced? Made in USA Jeep Cam bearing is self sizing. Is your Oil Pump removed? Is there anything way toward the rear near the expansion plug that is blocking the cam?
Use caution when installing your cam, the expansion plug at the rear can be unseated causing an oil leak at the rear of the engine.
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Re: Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 10:38 am

With the first bearing, I checked for burrs and found none. I inserted the cam backwards with the first and second bearings installed to determine where the cam was sticking. Both times, I found it to be sticking approximately 3/4s of the way inside of the bearing. I'm beginning to think there is a burr on the cast iron which is causing the bearing to compress in the area where the cam is sticking. Could be poorly made bearings but two in a row?. I don't recall the mfg(s) but I used two different suppliers. Obviously I'm going to have to pull the second bearing. This time I'll check the cast iron journal for the bearing for any obstructions or surface defects. Wish I had done this after the first bearing but chalked it off as a bad install by the machine shop. If you have any other thoughts, I'd appreciate it.

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Re: Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 10:50 am

The first bearing came from Walcks but don't recall the mfg. The second bearing came from Summit and the mfg is KGB part# CS101BB. Since I've got to buy another bearing, feel free to suggest an mfg and supplier. Part no. would be nice too. Gonna take a break from the project and head to MT for a birdhunt with my son. Hopefully when I return, I'll get this project finished. It's fun regardless. Why else would we do this, huh?

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Re: Camshaft bearing

Post by Joe Gopan » Sat Sep 23, 2017 12:57 pm

The Cam bearing is "self sizing" requiring no fitting or reaming.
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Re: Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 1:04 pm

Ben,

Can you recommend a supplier?

Thanks,

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Re: Camshaft bearing

Post by dpcd67 » Sat Sep 23, 2017 2:35 pm

We need to talk; the host of this great site, Ron Fitzpatrick, has all the parts you will ever need to restore a jeep; that is his business and he is the best in it, and is definitely the nicest guy too. He has new cam bearings in stock for ten bucks, US made. I can't fathom why guys will patronize other, unknown, parts dealers, and then come here and ask for help after they don't work. Maybe it's just me, but it's called loyalty.
Check your block cam bore too; it has an issue.
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Re: Camshaft bearing

Post by Joe Gopan » Sat Sep 23, 2017 2:59 pm

I've been installing Federal Mogul 1091M Camshaft bearing in 4 Cylinder L-134 Jeep since the 50's.
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
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COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO

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Re: Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 3:41 pm

Thanks. Will put it on order asap.

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Re: Camshaft bearing

Post by Cannon Cocker » Sat Sep 23, 2017 3:48 pm

dpcd67 wrote:
Sat Sep 23, 2017 2:35 pm
We need to talk; the host of this great site, Ron Fitzpatrick, has all the parts you will ever need to restore a jeep; that is his business and he is the best in it, and is definitely the nicest guy too. He has new cam bearings in stock for ten bucks, US made. I can't fathom why guys will patronize other, unknown, parts dealers, and then come here and ask for help after they don't work. Maybe it's just me, but it's called loyalty.
Check your block cam bore too; it has an issue.
I agree, I suspect the cam bore is likely the culprit. Two in a row bearing? I'll take a breather for a couple of weeks and then tear into it again. I'll post the solution when I have it.

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Re: Camshaft bearing

Post by artificer » Sun Sep 24, 2017 12:02 am

Can anyone tell me how a perfectly round properly fitted camshaft bearing can stop the perfectly round front camshaft journal going in that last 1/4 of an inch?
IT CAN'T!
So I'd suggest, stop replacing what is not causing the issue, establish precisely what the problem is & fix it.
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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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