Crank/bearing Questions

[James_03]

Hey guys,

Recently I pulled the bottom end off my rb30dett only to find the bearing shells looking like shit. Basically they were polished on certain parts of the bearing. I wasn't too sure if this was normal or not (suspected not) so I took the crank out and took it to a local engine rebuilder for an opinion.

Basically the guy went thru and measured all the journals etc, and then told me it was just out of minimum standard tolerance. They told me I could "probably get away with it", but I opted to not "probably get away with it" and have it done right.

Ok so they then recommend having the crank ground then a linish, and told me to get 10/10 bearings? whatever the fck that means. I assume 0.25 o/size but can anyone confirm?

Now my other question, I asked them if they needed the block/rods brought in as well and they said no?

So are they skipping something here? I want it done right this time so please let me know if they should be checking anyting on the block/rods before I re-fit the crank with o/size bearings.

Cheers.

Edited October 28, 2009 by James_03

[r33_racer]

0.25mm is 10 thou. Most shops work in imperial, so they refer to things in thou.

They should be checking the block for tunnel straightness, the big ends of the rods and small ends for that matter. Should get them to check everything regardless of what they said, or goto a different workshop.

Were the big end bearings polished, or mains?

[James_03]

0.25mm is 10 thou. Most shops work in imperial, so they refer to things in thou.

They should be checking the block for tunnel straightness, the big ends of the rods and small ends for that matter. Should get them to check everything regardless of what they said, or goto a different workshop.

Were the big end bearings polished, or mains?

Yeah it was the mains that were bad.

The motor has done next to no k's at all, so I think it was simply linished then chucked back in out of spec, *sigh*.

Any recommendations on bearings? It had King's in it, thinking of going ACL racing this time. Ill take the block/rods back in and request that they check it regardless.

Cheers.

Edited October 29, 2009 by James_03

[Ziller]

Yeah it was the mains that were bad.

The motor has done next to no k's at all, so I think it was simply linished then chucked back in out of spec, *sigh*.

Any recommendations on bearings? It had King's in it, thinking of going ACL racing this time. Ill take the block/rods back in and request that they check it regardless.

Cheers.

This is not sounding good already, do some research and go to a known RB26 engine builder and tuner in your state?, it will save you all round.

[James_03]

This is not sounding good already, do some research and go to a known RB26 engine builder and tuner in your state?, it will save you all round.

Yeah true.

I was actually thinking of doing that, they have already started on the crank so can't get out of that now. What I might do is take the block/crank elsewhere again once I get it back.

Thanks all.

[r33_racer]

Were all the bearings polished and evenly? Or just no1 and no7 and only on the inside half?

Edited October 29, 2009 by r33_racer

[boostn32]

where are you located james