Pitting on crank

[Nollaig]

Hi guys,

This is a picture of an RB30 crank that has 1 connecting rod journal pitted slightly.

Anybody know whats the limit for grinding a crank and also would you class the extent of this pitting.

[r32-25t]

It’s stuffed just like the block

[Nollaig]

Have you seen a crank this bad or worse r32-25t?

Just curious on your statement as I dont know the limits of a regrind on a crank.

[NZ-GTT]

Take it to a machine shop and they will measure it, check for cracks and straightness. RB cranks can be ground undersize.

Don't believe all the hype about them being nitrided it's a fallacy.

[BK]

4 hours ago, Nollaig said:

I dont know the limits of a regrind on a crank.

I've had cranks reground. 20 thou (0.5mm) max regrind as you're limited on the bearing sizes available for an RB. Steps are standard, 1, 10 and 20 thou undersize. Obviously it would be crack tested first before any work as mentioned. Looking at it, it might not be doable and if it is it would be definitely a 20 thou regrind for sure to be at all useable.

That crank is also not "slightly" pitted. Looks like it's been left outside in the rain for a year.