rebiuld questions

[Camaroman1221]

i am rebuilding my 3800 motor in my camaro that has 120k miles, should i replace the crank shaft? I didn't spin a bearing or anything and the crank isn't damaged.

[bigbrian442]

Re: rebiuld questions

You should at the minimum have a machine shop check it out.

[97rs4life]

Re: rebiuld questions

i am rebuilding my 3800 motor in my camaro that has 120k miles, should i replace the crank shaft? I didn't spin a bearing or anything and the crank isn't damaged.

no need, just have a machine shop clean it up and check it out for you

[ssms5411]

Re: rebiuld questions

I had mine rebuilt at 122,000 miles and the mechanic checked out everything and then used clev.77 bearings all around and it has been running great ever since with 168,000 miles on it and 7 years later.

[Camaroman1221]

Re: rebiuld questions

ok i screwed up the #1 bridge for the crank shaft trying to get it out, anyone know the part number or if i can even get one off of GM Parts Direct?

[bigbrian442]

Re: rebiuld questions

ok i screwed up the #1 bridge for the crank shaft trying to get it out, anyone know the part number or if i can even get one off of GM Parts Direct?

Do you mean the main cap?

[Camaroman1221]

Re: rebiuld questions

Yup that would be then, forgot the name of them for a minute

[bigbrian442]

Re: rebiuld questions

If you need to replace a main cap on a block, you need to have the block line bored after the replacement. It may be cheaper finding another block.

[Camaroman1221]

Re: rebiuld questions

oh great, ok i am gonna have to look at the cap and see what i did to it cause i only think there is a nic on the top part of it from me wiggling it, the part were the cap touches the black and were the bearing sits are untouched

[bigbrian442]

Re: rebiuld questions

oh great, ok i am gonna have to look at the cap and see what i did to it cause i only think there is a nic on the top part of it from me wiggling it, the part were the cap touches the black and were the bearing sits are untouched

If the cap doesn't fit against the block tight the clearence will be off on the bearing to crank. If you burred it, you may be able to just remove the burr.

[Camaroman1221]

Re: rebiuld questions

ok thats good to know because the parts that is messed up alil bit is not the sides or bottom where it contacts the block, is the part on that top so i should be ok

[bigbrian442]

Re: rebiuld questions

ok thats good to know because the parts that is messed up alil bit is not the sides or bottom where it contacts the block, is the part on that top so i should be ok

As long as it is not bad enough to effect the strength of the cap it should be fine.

[cam98aro]

Re: rebiuld questions

ok thats good to know because the parts that is messed up alil bit is not the sides or bottom where it contacts the block, is the part on that top so i should be ok

can you take a picture?

im betting that it is fine and you can re-use it

a nick on the top of the main cap doesnt seem like a threatening problem on a 200hp engine

[Camaroman1221]

Re: rebiuld questions

i'll get some pics of the cap when i get off work and post them up

[Hib Halverson]

Re: rebiuld questions

i am rebuilding my 3800 motor in my camaro that has 120k miles, should i replace the crank shaft? I didn't spin a bearing or anything and the crank isn't damaged.

Crankshaft replacement is usually not required in a rebuild.

First thing to do with the crank is have it magnafluxed and checked for straightness. If it passes those two tests, then it's journals need to be inspected for wear and machined undersize if necessary. If there is no significant wear, simply have the journals micropolished.

As for bearings, I think that, right now, the best stuff comes from Mahle Clevite. If the crank didn't need undersizing, use either standard or -.001 bearings to get the desired main bearing clearance.