Cam bearing R&R

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gzig5

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I got my block back two weeks ago from the shop. Had it tanked, honed, and new cam bearings. Just noticed tonight that #4 cam bearing is not clocked correctly. Almost 2/3 of the oil port is blocked. Can the bearings be removed and installed again to get to that incorrect one? Or will they be damaged on removal? I want to understand what reality is when I talk to them. Hopefully they will step up and do the right thing.
 
Its hit or miss, you may get lucky. Cam bearings are cheap, I would just buy another set.
I have seen them not lined up from the factory. Post a pic, might not be the end of the world to leave it be.
 
I have long drills I run down from the head surface, and main bearing saddle, to open up the holes.
Dress the bearing surface as nec.
 
Just gonna suggest that. That runs straight up from the crank saddle.
 
I’ve got a Snap-On cam bearing tool ! It works really well !! I’ve never messed up any cam bearings taking them in or out !! You can probably reuse them !! But anytime I have reinstalled a cam bearing the bearing itself just doesn’t feel like it as the same crush to it ( for lack of a better word ) . Cam bearing are cheap ! Why risk it !!
 
I would do like I do in any situation where I paid somebody to do a job and they didn't do it right. I would take it back to them and let him do it right..
This shouldn't be rocket science for machine shop...


Title of this thread what is a "can" bearing??
 
You may be fine with it clocked, our 273 had bearings installed by longtime mopar machinist. No issues.
 
Take it back. That is off too much. I have knocked 1 out then used lock tight when I reinstalled it. 20 years it’s still going strong. Kim
 
Rmoore said:
I’ve got a Snap-On cam bearing tool ! It works really well !! I’ve never messed up any cam bearings taking them in or out !! You can probably reuse them !! But anytime I have reinstalled a cam bearing the bearing itself just doesn’t feel like it as the same crush to it ( for lack of a better word ) . Cam bearing are cheap ! Why risk it !!
Click to expand...


You are right about the bearings don't seem to have the same crush when reinstalled... Due to the press fit, every time you remove the bearing and then reinstall it, it looses some of its retention force...
 
gzig5 said:
I got my block back two weeks ago from the shop. Had it tanked, honed, and new cam bearings. Just noticed tonight that #4 cam bearing is not clocked correctly. Almost 2/3 of the oil port is blocked. Can the bearings be removed and installed again to get to that incorrect one? Or will they be damaged on removal? I want to understand what reality is when I talk to them. Hopefully they will step up and do the right thing.
Click to expand...


2/3 blockage is too much... You should not have more than 50% overlap in the holes for the cam bearings and the oil feed holes...

Get it fixed one way or another...
 
inertia said:
I have long drills I run down from the head surface, and main bearing saddle, to open up the holes.
Dress the bearing surface as nec.
Click to expand...


I wouldn't recommend drilling the bearing in the block... How are you going to knock down the sharp burr/edge that it pushes through... It is difficult to be able to get into the cam bearing and re chamfer the oil feed hole after you drill it...
 
krazykuda said:
I wouldn't recommend drilling the bearing in the block... How are you going to knock down the sharp burr/edge that it pushes through... It is difficult to be able to get into the cam bearing and re chamfer the oil feed hole after you drill it...
Click to expand...

Not a problem , drill it out ------------
 
Sorry but you paid for a machinist to perform the work properly. Bring it back and have them do it right. That’s the problems of the world- no accountability and no reason to get better at something if nobody complains. What else did this person forget?
Make sure they run the cam thru it before you leave. I’ve seen too tight of bearings. If you don’t have the cam I understand. JMHO.
 
inertia said:
I have long drills I run down from the head surface, and main bearing saddle, to open up the holes.
Dress the bearing surface as nec.
Click to expand...
I was thinking about this as well. Worst case if it tears out is I have to change them anyway. I would grind the cutting end like an endmill so it would cut on half the hole.
$50 isn't a lot of money, but this wasn't my fault so I don't see why I should eat it. Should find out this afternoon. If they won't own up they will lose future business and I'll be telling anyone that will listen at shows and swap meets who not to use.
 
Syleng1 said:
Sorry but you paid for a machinist to perform the work properly. Bring it back and have them do it right. That’s the problems of the world- no accountability and no reason to get better at something if nobody complains. What else did this person forget?
Make sure they run the cam thru it before you leave. I’ve seen too tight of bearings. If you don’t have the cam I understand. JMHO.
Click to expand...
I stuck a wire down the oil pressure sender port and measured 7.5" which I am led to believe means that the plug is in there. They seem to have gotten the diameter of the oil pump shaft bushing correct as well. I'm hopeful they will acknowledge the error of their ways. He said they checked the bearings with a cam, but I still have the old cam or a new Comp XE275HL that I can take to check with.
 
Opening up the oil holes does no harm, saves a lotta drama, and chasing around, wasting time.
I clean up the babbit with a tapered stone, twisting between finger and thumb, a little patience, - tongue in the right position . lol

Plug under sender 7 1/2 ish" is correct.
 
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I've got the proper tools to debur the hole if it comes to that. I've scraped in the babbit bearings on a lathe spindle and this wouldn't be much different. Just hope it won't come to that.
 
famous bob said:
Not a problem , drill it out ------------
Click to expand...

I did mine about 10 yrs ago , easier/faster than hauling back to the machine shop , 2 towns away ------------
IMG_0474 (1).JPG
 
The shop said to bring it by and they'll replace the bearings. Hope to drag it over there this afternoon.
 
Job done. They were cool about it. Did it with the block on the tailgate. Knocked it out, cleaned and dressed everything back up and put it back in. It went in tight. Now we can all get back to more important things.
They had a 1965 Ferrari V12 engine block setting on the floor. Just had new cylinder liners put in and they are going to deck them 3 though above the aluminum deck. There is no head gasket, the liners seal directly to the head. Pretty cool. I don't think I'd leave that thing standing on the floor though

0EF3DA13-E1F2-440A-8674-A567AAA2C817.jpeg
 
gzig5 said:
Job done. They were cool about it. Did it with the block on the tailgate. Knocked it out, cleaned and dressed everything back up and put it back in. It went in tight. Now we can all get back to more important things.
They had a 1965 Ferrari V12 engine block setting on the floor. Just had new cylinder liners put in and they are going to deck them 3 though above the aluminum deck. There is no head gasket, the liners seal directly to the head. Pretty cool. I don't think I'd leave that thing standing on the floor though
Click to expand...

That's good. Sometimes though, the camshaft bearings are drilled in such a way that you cannot line one hole up without another being out a little bit. They aren't always perfect. I suspect the small misalignment you described would have hurt nothing, but I 100% agree that you paid for it to be right. Good for them. I would be using their services again.
 
You are correct. He got it clocked right, and the hole to the main is pretty much dead nutz, but the hole going up to the head is about 75% open. That should be enough, not their fault.

I added a pic of the v12. I couldn't believe how small and tight that thing is. Pic doesn't do it justice.
 
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