8ba oversized cam bearings... .080

chuck stevens

chuck stevens

Well-known member
Just called my machinist and he told my my block has .080 oversized cam bearings from the factory. I thuoght I was on easy street, bore cleaned up at .020, no cracks, everything else cleaned up real nice, now this. Has anyone ever hear of this? And the big question where can a guy find new .080 cam bearings, thanks, merry Christmas, Chuck. Oh yea it's a 52 eab.
 
yep seen this before , let me do some checking & also try barnfind07 here on the F/barn
Cheers
Tony
 
Another thing...can you get hold of the old ones? Just in case...these are generally very low wear items. If there isn't evidence of significant wear, if they were removed properly without distortion, if new ones cannot be found...I would not be worried by re-use.
With a machinist involved, I do know they like to trash everything that isn't iron savagely!
Remove'em with a cape chisel, scatter them in a 3 cubic yard dumpster...
 
Chuck,
Cam bearing oversize/undersize is always confusing to me (like a lot of things). I think if the cam journals had to be ground then you would need undersize bearings on the ID. If the block had to be bored (why?) then you would need oversize bearings on the OD. Maybe someone can enlighten me. This will be an interesting thread for me. To Bruce's point....if the proper tool is used they drive in and out without damage. If they have the old ones measure them up. Thanks
John
 
Yes, use the old ones, they're the best lubricated, least loaded bearing in the engine. Not only that, but some of the aftermarket bearings are poorly made and have larger than stock clearances. Something else you have to check when rebuilding an engine.
 
You'll never be to old to never hear about something different on a flathead. I've had 2-3 engines to build in my lifetime with .010 over cam bearings. I can usually locate them BUT, why any engine need .080 cam bearings? Unless the factory casting was screwed up and the factory had them back in the day so they just lined bored to saved the block. Walt
 
I made a fast trip to the machine shop this morning to catch up with those bearings before they were scraped. He saved them, so I got some pictures. We are trying to locate some new ones, but will reuse the originals if we have to. They have a ford script stamped on the back side... looks like this engine was a Monday or Friday masterpiece.
The old bearings weigh twice as much as the new replacements. Thanks for all your help,
Chuck S.
 

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You may want to measure your cam as the bearings that the
parts book show with oversize OD also had undersize ID.

Bob
 
The cam line was bored oversize to save a core shifted block. A fairly common practice.
The old bearings might work. The bottom line is if the ID is within tolerance AFTER
re-installation.
If all else fails, bearings can be made from bar or tube stock. Either bronze or aluminum. We do that for race cams over .420 lift where the cam line has to be enlarged..
 
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Chuck you left a message with me you need these bearings I said I would look and I do have them. Call me again I have been trying you all day since 8 this morning are your lines down? Fred
 
Thanks for all the help, just a few years ago, with out a computer i would have been up the creek. I think we have a set, will check tomorrow, Chuck S.
 
Pete said:
The cam line was bored oversize to save a core shifted block. A fairly common practice.
The old bearings might work. The bottom line is if the ID is within tolerance AFTER
re-installation.
If all else fail, bearings can be made from bar or tube stock. Either bronze or aluminum. We do that for race cams over .420 lift where the cam line has to be enlarged..
Click to expand...


So my notebook entry should say blocks with .080" over cam bearings may be bad candidates for max overbore?

Lonnie
 
Binx said:
So my notebook entry should say blocks with .080" over cam bearings may be bad candidates for max overbore?

Lonnie
Click to expand...

Overboring the cam-line should have NO affect on the cylinder bore.
The last flathead race engine I built had the cam-line bored to 1.928.
The cylinders were 3.440.
 
The core Pete is refering to is the cam core. The blocks were made up of a lot of different wax cores all wired in place inside the mold. Shift can happen with several of the cores.
 
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