noisy sbc

[565bbchevy]

The back of all the bearings will be marked with the undersize on them .010,.020,.030 you can just get new bearings if you need to, or just inspect everything and reinstall them. If you start changing parts make sure you check your clearances. I wouldn't change the rings, your main concerns are the rod and main bearings, and the cam bearings if metal passed through the motor, and the cam, lifters, and timing chain if the end play wasn't set correctly like said above. If the bearings are all junk a thorough block cleaning is in order as well as a new oil pump

X2
I would also make sure when you set up the endplay for the cam that you make sure the cam button fully engages smoothly into the hole where the cam locking plate
is and since the cam locking plate was basically designed to retain a cam button I would open the hole up to match the cam sprocket so there is no ridge for the button to possibly get caught on since there will be an in and out movement in the hole unlike a cam mounted button that moves with the cam.

 

[mebe007]

I think that was the problem. The hole in plate is smaller than can gear. Things were riding on the wrong things. I think I'll order a new button from clouds while I'm at it

Also how would I inspect the can bearings or see a problem. Also I'm thinking the oil pump should be replaced. Machinist swore to run high pressure pump. All new to me but that + street clearances gave me like 50psi at idle

 

[mebe007]

OK so tore it all down today. First things first there was a little bit of oil in some of the cylinders. Could this be from excessive oil pressure blowing by the rings? Crosshatch is still present in cylinder bores. A few of the pistons look to have some micro fine scratches on the skirts. I cannot grab a nail on it.

The journals appear to be of and the bearings didn't seem scored. The dam bearings looked fine to me.

I'll post pictures but tell me what you guys think, re ring it since blow by ( or leave it), new main and rod bearings, new oil pump, new timing set and button it back up?

 

[mebe007]

 

[mebe007]

 

[mebe007]

 

[mebe007]

Rod and main bearings both stamped .010"

Tapped can on one bearing on accident. Left a mark but no groove

 

[crotchss]

Pistons and cylinders look normal, bearings all look good. I would guess the filter caught most, if not all, of the debris. Also with the cover being aluminum that's a lot better than steel going through it. I've never used a timing cover like that. I've always used the roller bearing cam button retained with a lock plate like you have, but put in the cam nose pushing on the cover. BTW how much cam play did you have? Also what weight of oil are you using?

 

[565bbchevy]

It appears most of your shavings stayed in the timing cover area, did you see any in the pan?
Unless you noticed excessive oil blowby when it was running I'm thinking that is probably not an issue as long the rings look good and you set up your ring pack correctly.
Was there a thrust washer or Torrington bearing under your cam gear?
Also was this cam degreed in?
For the most part from what I can see in your pictures is just normal wear from a running engine on your cam and bearings, the micro scratches in your cylinder walls
and on piston skirts are typical when the assembly is not contamination free but if you say "they are not grabbing a nail" they should be fine.
If the crank has no scratches at all I would reinstall it but I personally would replace the bearings to me it is cheap insurance since they have already been torqued
and crushed and show some minor scuffing along with the fact that factory SBC caps are not really designed with perfect alignment.
As you already stated about replacing the timing chain set and oil pump also cheap insurance and hopefully this is the last time you assemble this engine.
Just take care in the assembly process and make sure everything is as clean as possible and when it comes time for the timing chain and cover assembly do multiple
mock ups and verify everything.
Make sure the cam button fully seats on the cam when all the way in and like I stated earlier open the locking plate hole equal to or greater than your sprocket hole.

 

[mebe007]

Yes the can sprocket has the roller bearing built into the back. Not sure of forward movement of can but was surely enough. You think I should leave the can bearings alone? Just replace the mains and rods? How do I determine ring condition? Could the oil have been from excessive pressure and not enough run time yo seat them? Also standard volume or high volume oil pump? Which bearings would be recommended?