Cam bearings

marcjagman · Post by **marcjagman** » Thu Sep 08, 2011 6:38 pm

Does anybody know of a good way to fit cam bearings? Don't want to damage the ones I have just bought by using the wrong tools. Wondered if putting them in the freezer overnight would make it a bit easier to get them in.

ChrisJC · Post by **ChrisJC** » Thu Sep 08, 2011 7:39 pm

You need special tools. I have drawings, but you'll need to be mates with somebody with a lathe.

Chris

marcjagman · Post by **marcjagman** » Thu Sep 08, 2011 7:46 pm

Can you send them to me please?

101sean · Post by **101sean** » Thu Sep 08, 2011 7:57 pm

I cut an old camshaft up and faced up and drilled the bearing sections in the lathe. Then used them inside the shells with a larger piece outside to drive them. Found it easier to tap them in rather than draw them in with a threaded bar

stevieturbo · Post by **stevieturbo** » Thu Sep 08, 2011 8:21 pm

I haev successfully installed them in a R8 before by tapping them into place.

But after recent problems with my current engine, it seems the best way is to pull them in.

Have a puller made up to fit inside the bearing, nice snug fit with an edge so the bearing is secure.

Have another section made up, with a shallow taper. This will be used to pull against at the opposite end of the block.

Then a piece of threaded rod up the middle and use this to pull the bearings in.

And have to say, this is one of my better drawings !! lol

Blue bit is the bearing, in case it wasnt obvious.

Uploaded with ImageShack.us

marcjagman · Post by **marcjagman** » Thu Sep 08, 2011 9:08 pm

Thanks, will have to get some pullers made as all the bearings are differents sizes, excellent idea though.

stevieturbo · Post by **stevieturbo** » Thu Sep 08, 2011 9:23 pm

DO specify a shallow taper on the piece.

I just specified 45 deg for the one I had made, and whilst ok, it will not centralise as positively as I'd like it to. Although they also made the tool quite short, as I didnt give detailed enough measurements.
My own fault, although it will still work fine.

If the bloody bearings ever get here !!

ChrisJC · Post by **ChrisJC** » Thu Sep 08, 2011 9:28 pm

Download it from:
http://www.cowdery.org.uk/downloads/V8-Cam-brg-tool.pdf

Drawing doesn't show a large tapped hole in the middle of each part, and a long length of studding to draw the bearings in.

Chris.

stevieturbo · Post by **stevieturbo** » Thu Sep 08, 2011 9:38 pm

ChrisJC wrote:Download it from:
http://www.cowdery.org.uk/downloads/V8-Cam-brg-tool.pdf

Drawing doesn't show a large tapped hole in the middle of each part, and a long length of studding to draw the bearings in.

Chris.

Drift set implies banging them in or pressing them in. Ive done it before with no special tools.
Knowing what I know now, I'd be using the above technique and pulling them in slowly and hopefully the tool will ensure totally straight.

If you try and make the actual bearing part a suitable size so that only one tool is required, rather than many. If the OD of the bearings are different sizes, which they seem to do for some odd reason.

spend · Post by **spend** » Thu Sep 08, 2011 10:02 pm

You need a lead in in front of the bearing journal a tad smaller than the housing, and a press plate behind the journal just larger to stop when you've fully inserted the bearing. Use the smaller one to extract old bearings.

Measurements I used are:
Bearing Number.......... 1 2 3 4 5
Nominal OD............ 42.26 43.04 43.80 44.56 45.32
1/4” Inner clamp OD 44.76 45.54 46.30 47.06 47.82
1/4” Outer clamp OD 45.26 48.54 49.30 50.06 50.82

Then a plate Outside & to either pull out or pull in.
I run the studding all the way through from front to back to retain alignment, I had my tool opened up from M8 to M10 as that helped a lot.

Get the plates made up so that you can slot them onto the stud - you can do the whole lot in one go that way. All works fine if you have the crank out, just a lot lot lot more fiddly if the crank is in the way but do-able (one at a time threading / dangling / praying...). If you see them going in skewed a quick tap will pop them back square..

Some folks seem to try and misalign the oil hole to reduce flow, either by rotation or not fully inserting the bearing, I prefer to drill smaller holes and insert fully.