904 rebuild...this concerns me

[TylerW]

Hey guys:

I'm working my way through overhauling my '73 904. I'm doing the front clutch right now and I spotted something that doesn't look right. The pictures are looking down into the front clutch piston retainer..see those shiny spots on each of the lugs? Not sure what's going on there or if it came that way.

The trans had a totally burnt up front clutch, but otherwise everything else looks good...so far. The #2 thrust washer had a .002 wear groove in it, so I'll replace that. The planetary assembly overall thrust clearance was fine but of course I'll disassemble it anyway to check everything.

Thanks for looking.

 

[AJ/FormS]

I think I know what did that and why.
With the lined plates wore off, the piston simply went out too far and hit the rear clutch.

 

[TylerW]

I think I know what did that and why.
With the lined plates wore off, the piston simply went out too far and hit the rear clutch.

Cool, thanks.

 

[TrailBeast]

I think I know what did that and why.
With the lined plates wore off, the piston simply went out too far and hit the rear clutch.

Yup, no biggie.
Look and the splined end of the rear clutch and you will probably see the other end of those marks.
That end will be steel though so it may not be real obvious.