Cam Box Flange Question

[mikedsilva]

I went to clean the cam boxes from my 964 today...
Whilst they weren't very leaky before I pulled the motor, the surfaces are quite eroded...

Not sure what to do here... will it be OK with some sealant? And advice appreciated...

[mikedsilva]

I ended up having a crack on the wet and dry, on the coffee table!
Not sure how far to go.. It seems I need to go quite a lot longer..

[DRACO A5OG]

Wow, good job, Heck I didn't even do that, just brass wire brushed it and put it back together, no leaks so far

I will do it on the top end re-build though.

I think the main trick is proper gradual torque.

[Steve@Rennsport]

I use my belt sander to do the same thing.

Just as soon as its uniformly shiny on all the sealing surfaces, you are good to go.

[mikedsilva]

Thanks for the replies.. so I have a LOT more sanding to go.. not sure why the surface was corroded though..

Plan is to use threebond 1211 on the o-rings to seal effectively to the cam box as there is surface corrosion in that area too... good idea?

[KTL]

Corroded because it's magnesium. Magnesium tries to return itself back to the earth much faster than the heavier aluminum.

Tip for sanding progress like that is to color it with a sharpie marker and you can watch your progress that way. It's a good way to confirm you're done and no need to keep on going!

[prschmn]

These parts do seem to move around over time-like all castings but I would first check
preferably on a surface plate but short of that-the glass coffee table top will work pretty
well to tell you how far out of flat they are. The ringed factory gasket will tolerate around .010"
off and anything less than that all you really need to do is remove any loose scale/oxidation
from the surface to insure a leak free part. These things are soft and need to be treated carefully.
It's very easy to ruin the flatness with any kind of overly aggressive methods.

[Ken911]

granite kitchen counter tops are also very flat. glass table tops tend to flex sometimes. I learned that the hard way with my glass patio table that turned out not to be so flat.

[theiceman]

you use gaskets and orings for these locations so cleaning them up is all you really need, dont need engineering blue tolerances.