New cam bearings

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wantafaster1
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New cam bearings

Post by wantafaster1 »

I bought some ACL bearings to fit into my block, and have made some top hats to pull them into place. I'm wondering if anyone knows how much tighter they compress when in place? They are a little slack on the top hats now, just rattle and no more.
A bit worried they will be compressed so much and I will mark them trying to get the top hats out again.

Thanks for your help.
ianh1968
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Re: New cam bearings

Post by ianh1968 »

Can't you just pull them in with a piece of plain flat steel?
I am thinking a bit of 1/4" thick plate with a hole in it, a length
of studding a bit longer than the width of the block, another
plate, and a winding nut...

I don't use anything fancy to get trailing arm bearings and
bushes in, nor do I for the idler bearing in the gearbox case.
Most pullers that are not already purpose built get made out
of generic studding and various washers/plates and nuts...

Why does the puller need to be "hat-shaped"?

Ian
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dklawson
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Re: New cam bearings

Post by dklawson »

ianh1968 wrote:Why does the puller need to be "hat-shaped"?
Ian
To keep it centered and prevent the shells from going in at an angle.

I don't know the amount of collapse. However, make the small diameter of the hat slightly smaller (maybe 0.002" smaller) than the cam journals. You know that the cam has to fit in the installed shells and most accounts today say that scraping the shells to size is hardly ever necessary anymore.

EDIT: That said... why not take the shells and your cam to the machine shop working on the block? Have them install the shells and size them if necessary. They are set up to do both tasks.
Doug L.
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Spider
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Re: New cam bearings

Post by Spider »

As Doug has suggested, but I make them 0.010" smaller.
ianh1968
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Re: New cam bearings

Post by ianh1968 »

dklawson wrote:
ianh1968 wrote:Why does the puller need to be "hat-shaped"?
Ian
To keep it centered and prevent the shells from going in at an angle.
I think that you would have to try really hard to get them in at an angle...
Once you've got the first got the first 1/8" in, they will surely be "self-straightening"?

Having dedicated tools is obviously better and far more desirable, but in many
instances there is little or no difference to the end result if common-sense and
care are exercised during assembly.

What ever method is used, the most important thing would be to:
MAKE SURE THE OIL HOLES ARE LINED UP!

Ian
wantafaster1
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Re: New cam bearings

Post by wantafaster1 »

Works perfectly, but no matter what I ended up having to tap them square to get them started off properly. Thanks for the input lads, another job I won't be frightened of again!
wantafaster1
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Re: New cam bearings

Post by wantafaster1 »

I did end up having to make a bearing scraper though, just pushed up a little edge on the first one I did.
I ground a sharp edge on a clutch drive strap and then made it a bit banana shaped in the vice. My goodness bearings are soft.
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