What are the odds of cam bearings falling in? Again
#1
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What are the odds of cam bearings falling in? Again
Back then during a cam swap cam bearing # 3 came out pulling the cam off my LQ4, motor had somewhat low oil pressure so that was tend to happen.
I got it rebuild and made into an 05+ LQ9 w/ LS2 rods and pistons as well as all new Clevite bearings (Main, rod, cam, and crank).
When putting it back together the cam was pretty damn hard to put in after it was 50% In. They had to use a rubber mallet to slightly tap it in and an Impact drill to turn it (cause it couldn't be turned by hand) to get it in so it was a tight fit.
Motor now has about 1350 miles and oil pressure is ~65-70psi at idle, no knock and runs perfectly fine. I currently have a 228r cam but want to upgrade for something bigger for my 4200 stall and CNC'd L92 heads.
So question is; should I be worried about the cam bearing falling in again when I pull the cam?
I got it rebuild and made into an 05+ LQ9 w/ LS2 rods and pistons as well as all new Clevite bearings (Main, rod, cam, and crank).
When putting it back together the cam was pretty damn hard to put in after it was 50% In. They had to use a rubber mallet to slightly tap it in and an Impact drill to turn it (cause it couldn't be turned by hand) to get it in so it was a tight fit.
Motor now has about 1350 miles and oil pressure is ~65-70psi at idle, no knock and runs perfectly fine. I currently have a 228r cam but want to upgrade for something bigger for my 4200 stall and CNC'd L92 heads.
So question is; should I be worried about the cam bearing falling in again when I pull the cam?
#2
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I'm not quite sure what you're asking about "bearing falling in" ????
Each bearing should have between .001" and .002" interference fit in the
block bores which is why they need to be beat into place.
There are a few things that can cause the overly tight cam turn you had.
Sometimes the block bores need a few licks with a hone bar..similar to a line
hone on the mains but only a few turns/strokes to fix core shift or bore burrs
from a hack removal job.
Another thing that can happen is the edge of the new bearing can get dis-
figured or flattened from the hammering on install. Most builders will cham-
pfer the inner babbit to prevent the cam interference and after I do that I
also put the bearings in the freezer for about a half hour, which shrinks them
slightly so they install easier and less chance of wrecking the edge.
IMO your engine should never have been left to chance like that and the
obvious interference could have created a babbit burr on the edge now that
may fall into the engine upon removing the cam....kinda hit or miss really
Each bearing should have between .001" and .002" interference fit in the
block bores which is why they need to be beat into place.
There are a few things that can cause the overly tight cam turn you had.
Sometimes the block bores need a few licks with a hone bar..similar to a line
hone on the mains but only a few turns/strokes to fix core shift or bore burrs
from a hack removal job.
Another thing that can happen is the edge of the new bearing can get dis-
figured or flattened from the hammering on install. Most builders will cham-
pfer the inner babbit to prevent the cam interference and after I do that I
also put the bearings in the freezer for about a half hour, which shrinks them
slightly so they install easier and less chance of wrecking the edge.
IMO your engine should never have been left to chance like that and the
obvious interference could have created a babbit burr on the edge now that
may fall into the engine upon removing the cam....kinda hit or miss really
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#8
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Rubber mallet to install it and then an impact to turn it? That's really really really bad news. Like whoever built your engine should be shot in the head and/or both ***** so they can't reproduce.
Cams should slide in with virtually ZERO resistance, and you should be able to turn them almost effortlessly (If it's just the cam with no lifters). I could turn the cam in my motor with my pinky finger on the cam gear dowel. If you need anything more than a few ounces of force, then there's a problem; either the cam is bent, bearings are cocked in the block, or the bearings are the wrong size.
Cams should slide in with virtually ZERO resistance, and you should be able to turn them almost effortlessly (If it's just the cam with no lifters). I could turn the cam in my motor with my pinky finger on the cam gear dowel. If you need anything more than a few ounces of force, then there's a problem; either the cam is bent, bearings are cocked in the block, or the bearings are the wrong size.
#9
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Back then during a cam swap cam bearing # 3 came out pulling the cam off my LQ4, motor had somewhat low oil pressure so that was tend to happen.
I got it rebuild and made into an 05+ LQ9 w/ LS2 rods and pistons as well as all new Clevite bearings (Main, rod, cam, and crank).
When putting it back together the cam was pretty damn hard to put in after it was 50% In. They had to use a rubber mallet to slightly tap it in and an Impact drill to turn it (cause it couldn't be turned by hand) to get it in so it was a tight fit.
Motor now has about 1350 miles and oil pressure is ~65-70psi at idle, no knock and runs perfectly fine. I currently have a 228r cam but want to upgrade for something bigger for my 4200 stall and CNC'd L92 heads.
So question is; should I be worried about the cam bearing falling in again when I pull the cam?
I got it rebuild and made into an 05+ LQ9 w/ LS2 rods and pistons as well as all new Clevite bearings (Main, rod, cam, and crank).
When putting it back together the cam was pretty damn hard to put in after it was 50% In. They had to use a rubber mallet to slightly tap it in and an Impact drill to turn it (cause it couldn't be turned by hand) to get it in so it was a tight fit.
Motor now has about 1350 miles and oil pressure is ~65-70psi at idle, no knock and runs perfectly fine. I currently have a 228r cam but want to upgrade for something bigger for my 4200 stall and CNC'd L92 heads.
So question is; should I be worried about the cam bearing falling in again when I pull the cam?
#13
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when i did the 6.0 iron block tear down for my formula the number 3 cam bearing fell out, I got new cam bearings installed but nothing was beat with anything else