Cam Issue

[War Wagon]

The block has been fully preped along with new cam bearings.
We installed the cam tonight and when fully stabed in you can not turn it by hand. When you turn it with a wrench it will break free and start turning better. If you stop you have to use the wrench to start it turning again. Bearings were lubed with the cam break in lube. If you pull it out of the block to the groove in the front journal it will turn fine. Just for fun we installed the old cam and it turned fine by hand, now mind you this cam has 200,000+ miles on it. This is my first AMC build so not sure if this is right, myself I think not.

Jim

[82Waggy]

You should not use cam break in lube on the bearing journals. Use a good assembly lube instead, but not grease.

Cam break in lube is for lapping the cam to the lifters.

[JERSEYJOE]

I RAN ACCROSS THIS ON ONE OF MY 360 BUILDS. IT RAN FINE AND THERE WERE NO ISSUES.

[82Waggy]

I RAN ACCROSS THIS ON ONE OF MY 360 BUILDS. IT RAN FINE AND THERE WERE NO ISSUES.

Depends on the type of lube, but I would not use a molly paste type cam lube on the bearings.

I use Torco or Royal Purple assembly lube on bearings.

[War Wagon]

We had redline assy. lube and cam lube as well.

Jim

[tufcj]

It's a min/max thing. The bearings are at their maximum tolerance (making the smallest hole) and so are the cam journals (making them the largest diameter).

I had the same thing happen with my AMX 390. I thought I had a bearing in crooked, but they were all good, so I started measuring tolerances, and the cam was tight, about .001-.0015 on all journals. Mine was with a Crower cam. Probably a good thing, less bleed, so more oil to the main bearings. Hasn't been a problem so far.

Bob
tufcj

[82Waggy]

Might also be worth checking cam length/end clearance against the cam bore plug at the rear.

[War Wagon]

Thanks guys, we will check it out Friday, going to the track tonight for test and tune.

Jim

[1980_Cj7]

I thought the idea of having a specified clearance between the bearings and the journals was so there was room for a film of oil inbetween so that you don't end up with metal to metal contact and the resultant wear. In other words, tighter is not always better.

[luxi401]

might also be a slightly bent camshaft....

[War Wagon]

might also be a slightly bent camshaft....

We were thinking that too.

Jim

[Dusty]

could be a case of a shifted block. had two 360s shift on me to where intalling or removing the cam was an undertaking and also turning the cam was extremely dificult. it was only inside of the block that shifted around the cam area and even the machine shop didnt catch it when the checked the block. they ended up comping us with the machine work on a new block since they had checked it but still a pain in the....

[Mudrat]

Would a line bore have solved this???


could be a case of a shifted block. had two 360s shift on me to where intalling or removing the cam was an undertaking and also turning the cam was extremely dificult. it was only inside of the block that shifted around the cam area and even the machine shop didnt catch it when the checked the block. they ended up comping us with the machine work on a new block since they had checked it but still a pain in the....

[War Wagon]

Got it turning some better so we went with it. We will see how long it will last, hay ya'll watch this.

http://i73.photobucket.com/albums/i201/jwillettgn/6.jpg

http://i73.photobucket.com/albums/i201/jwillettgn/7.jpg

Jim

[ironman_gq]

I'd keep an eye on those aluminum bridges I hear they have a tendancy of breaking :shock:

[War Wagon]

I'd keep an eye on those aluminum bridges I hear they have a tendancy of breaking :shock:

Thanks for the heads up, I have a set of steel ones on another motor I have that I could use. Would I be better off?

The Cam specs are 212/218 duration @ 0.050" lift.
.477/.484 lift on a 110 LS
We set it a 4 degrees advanced
Springs are CC 926-16


Jim