Not sure that this is the right forum for this question. I have a 1997 350 Chevrolet that the front cam bearing had come out while running. The issue is that a new cam bearing will slip right into the block. I've been looking for an oversized set to put into it. I found a set listed as being 2.030 diameter, whereas the stock bearing is 2.024. This is . 006 thousands bigger than the stock one. My question is, how much of an oversize is required for a good fit? I can't find anything that says what the block bore for the camshaft should be. If I knew what it was supposed to be, I could figure out what size I need to fix this engine. It was only run less than 10K miles if that. Block is basically new. It's a shame to just have to junk it because of one bearing. Any ideas on where to find the clearance specs for the bearing to block? Many thanks for any help you can offer. Cadman-iac
The cam bearings are a tight drive in fit with the proper tool to keep them in line and straight. Clearance for the bushing to the block is zero. Are the rest of the bushings damaged? I ask because it doesn't necessarily mean you have to replace all of them if they are good, not ****ed and tight in the bores. The ID is the important part. The OD size doesn't matter. You can take the engine to any good automotive machine shop and have them ream the bearing bore to fit the oversize bearing. Not a major project. They may also need to ream the ID for proper running clearance. Is the bearing surface on the camshaft damaged? A good guess on the bearing to cam journal clearance would be in the .001" to .0015" range. Not a job for the person without the proper tools and knows how to use them.
The engine has been out of action since 1998, the internals were used in another block. But I've been looking at this one as a replacement for the one in my 88 burb. I have the bearing installation tool for this. My main concern is that I don't know how much oversized the front bearing bore is. I'm unsure if the oversized bearings are actually big enough to stay in place, as I know they are a press fit. I just don't know how much "squish" is necessary. Hopefully this will not be needed, I have to dis***emble the engine coming out today, then I'll know more. As for your other question, the remaining bearings are all in good shape and still in place. Not sure how this one made it out of the factory this way. Thanks for your reply. Cadman-iac
I got that part. What I'm trying to find out is how much "interference" it's supposed to have. Is it .005", .008", .010", or what? I guess I'll have to ask a machine shop for that information. I just pulled the engine out of another vehicle and took the front cam bearing out and measured the hole, and if I did it right, the standard bearing would have about . 005" of interference fit. But I'd really like to confirm that. Thanks for your reply. Cadman-iac
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