D282 camshaft bearings

Good afternoon all. I am seeking advice as to the proper way to size new camshaft bearings after installation. After searching the forums here and recieving "advice" from various sources, I have come to the conclusion that there is a difference of opinion on this. I have done various rebiulds before but this is the first time I have installed single piece bearings. The old bearings were drawn out correctly with a threaded rod and properly sized puck, so no damage to mating surfaces. New Clevite bearings were installed in the same manner. No hammers here! The bearings fit nicely on the new cam which was in tolerance when miced. So, that being said, the bearings after install are to tight. No surprises there. The confusion is how to size them. I have heard to use a brake caliper hone, a bearing scraper, inline boring, to force it in and let it burn clear. The two options I am considering are a hone or inline boring. The hone seems the most economical but was told to avoid this because of contaminants getting into the bearing. Inline boring seems expensive for a simple fix. Bearings are straight and round and I need about .002 off. Any advice on this would be greatly appreciated!
Thanks. Art the beekeeper.

To do it right you need to have it lined bored. I know it's spendy but thats about the only way to insure it's right and not trying to flex the cam shaft. Trying to scrape or hone it bearing by bearing could lead to a broken cam. I myself have just installed the cam and run it, not on that engine but on others. I've never had a problem with one as long as i could get the cam to turn a little before the lifters were installed.

IMO, getting camshaft bearings installed properly involved the use of a camshaft installer tool. Did you use this tool, or did you just pound the bearings in?

Beekeeper,
I had a similar problem with an Idler Gear
bearing in a Cub engine. The bearing went into the gear with no problems but instead of having 0.001"- 0.0025" clearance, the bearing was undersized approximatly 0.004".
I spoke to two Machinists and they both told me the same thing; use 800 or 1000 grit wet/dry sand paper over a brake cyclinder hone and lube with WD-40.
It took about 2 hours but the clearance is now within spec and the bearing is much smoother than when I started.
I found that using heavy-duty double-sided tape over the stones on the brake hone then wraping the sand paper over the tape works fairly well.

Good luck,

Art

I have seen cam bearing spin in the block when fitted too tight. The secret to putting in a cam bearing is having the proper size driver, it should be a trifle larger than the journal on the cam shaft, like so you can just barely slip the bushing on the driver installer. The adjustable type can be a problem on some bearings. On the 282 you should not need to ream the bushings. If you can put the cam in and run it with an electric drill off and on until it is free you will be good to go. I have had to do this when I no longer had access to a really good installation tool and thought what I was using was good enough. Patience is the deal with these . Never use a hone unless they are solid brass which I am sure they are not, never saw that in a 282.

this is a german deisel and the cam bearing need to be line bored.

(quoted from post at 21:54:03 01/21/10) this is a german deisel and the cam bearing need to be line bored.

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You are correct that the German diesel engine (D310 and D 358) needs the bearings line bored after assembly but this is a D282, American made.

I have never had a problem with any of these diesels or similar gas engines (same bearings) but I do have the IH special tools to install them with.

I have had the cam installed and it does turn with resistance. The resistance is constant throughout the revolution, so I believe the cam and journals are inline. Inside mic confirms this. I am concerned about getting the proper clearance to obtain the oil "pillow" and not be oil starved. Perhaps I am being to critical on this. I have enjoyed rebuilding this motor but I have a hunch I would not enjoy it a second time so would like to get it right.

The cam turns at half crank speed. If you can turn it by hand with the gear it should be ok. Make sure the oil holes are all lined up so it gets a good supply to keep them cool. You can use a clean piece of oak & a hammer & hit the cam on as many ways as you can to try & gain a little more clearance. If nothing else , take the cam to a shop that grinds cranks & have them polish it down a thousand or two.

Thanks to all for the wonderful insights!! It is nice to know that there are others that have a reverance and appreciation for times gone by and the equipment that has built the ag industry to what it is today. I will try to post a completed project picture, but am a newbie to the computer thing.