Main bearing question

[Randall]

Hey everyone,
I just wanted to ask, when do you replace the main bearings? Is it necessary without a rebuild needed? I am going to be installing a used motor into my SHO and I wanted to know if in addition to rod bearings, I should replace the mains. Thanks for any advice!

 

[SHOtime2511]

you can pass on the main bearings if you want!

 

[Off Road SHO]

If the rod bearing and journals aren't in bad shape, such as scoring, more than likely the mains are okay.

Tom

 

[AREA 91]

So far, I haven't seen any really worn main bearings. The mains usually last twice as long as the rod bearings. You will be fine.

 

[somedude_001]

this is actually a good question, i purchased a set of main bearings for my car but haven't installed them yet. i'm over 216K and since the turbo is almost ready i figure it couldent hurt.

 

[Randall]

Great! Thanks for the input guys. Would you recommend that I pull a main cap and check the bearing on the cap side before dismissing the idea? If so, do you just yank the cap off, check the bearing, and then put the cap back on and re-torque to spec?

 

[yamahaSHO]

On an NA car, the main bearings should last a long time. On my SC car, the bottom bearings had a decent amount of wear.

 

[Off Road SHO]

On an NA car, the main bearings should last a long time. On my SC car, the bottom bearings had a decent amount of wear.

That's because your supercharger is trying to drive the crank through the pan and into the asphalt.

Tom

 

[Off Road SHO]

Great! Thanks for the input guys. Would you recommend that I pull a main cap and check the bearing on the cap side before dismissing the idea? If so, do you just yank the cap off, check the bearing, and then put the cap back on and re-torque to spec?

Yes.

Tom