Rb26 Crank Keyway/balancer

[aaronjod]

Hey guys,

Noticed my harmonic balancer was a little wobby, and it spat a power steering belt once so futher investigated.

Front crank seal was leaking so figured i'd have to replace it.

Got a 2nd hand Balancer and new crank seal and went to do the job today when i found this...

Basically the balancer has been on loose, flogged out the Keyway/Balancer/Shaft. Now i realise to properly fix it i'm looking at crank out - Reweld and redrill etc or new crank.

What i want to know is has anybody had any experience with other repairs? I was thinking liquid metal? Realisticly it's a stock motor, and eventually i will have to rebuild it later down the track, but do you think i would get a couple of years out of a cheaper repair as such? With a new keyway and balancer, there would only be a little bit of play left in the crank hopefully able to be repaired with liquid metal. It does look like majority of the damage was done to the keyway not the crank.

[t_revz]

I personally don't have experience with this exact problem but I would much rather a modified key to suit rather than liquid metal alternatives.

I would discuss with your/a builder

[MrStabby]

This has been discussed before - a number of ppl have had the same issue. IIRC the suggestion was to get it built up with weld and machine it again, but my memory could be off - search here and in Forced Induction and i'm sure you'll find some threads. Also the torque spec for the balancer bolt on RB26s is huge (?400 or 450? Nm), so im guessing these problems have occurred because some crappy mechanic hasn't tightened it enough.

[GTRsean]

Happened to my 32GTR I had. Had the machinist put a keyway in the opposite side of the crank.

[Pezhead]

I also had a similar issue when I did mine.

Since the crank wasn't out, I decided to custom grind a new key to size. I first found a 1/2 round that was the same width and then reshaped it on the grinding wheel until it seated completely in the 1/2 round bit.

Then I lightly skimmed the top 1/2 to size for the pully. Now it means that my timing mark is slightly off but way better than it was with that opened keyway.