Experts On Cleaning Magnesium Needed!!!

[Craig Roche]

A call to wealth of experts!! I'm trying to clean my transmission case and not having much luck. It's a 915 and looks like a combo of aluminum and magnesium pcs. Has anyone discovered an effective way to clean these up. Seems to be alot of discussion about how to handle the magnesium. Everything I put on it makes it worse!! Help!!!

[dvkk]

A friend of mine swears by using spray-on oven cleaner. He only does it on rebuild time when there are no other parts around but the Mg case. It might be touchy to do it with the trans in the car.

[Early_S_Man]

Craig,

I would strongly recommend against using any kind of strong alkali or chemically-active solvents or cleaners on a transaxle case!

For simple cleaning a coin wand wash does wonders for getting off years of road grime and petroleum build-up ... spend a couple of $$$ at the car wash leaning over and sraying the sides and underside of the 915.

With the car up on jack stands and the rear wheels off ... a home pressure washer would do the most effective job! After that, out comes the spray cans with Brakleen or carb. cleaner ... to remove the stubborn spots.

[surflvr911sc]

"1984 911 Targa"
If this is the car the trans is out of, it is aluminum.

Whatever you clean it w/ rinse w/ plenty of water before it dries on it. Once you have the heavy crud off, brake cleaner and a wire brush works great for the tough spots.

[Craig Roche]

Thanks all for the reply! I'm trying to make it look as good as yours does Ryan. I've been silently checking your progress, very very nice I must say!!!! Seems like the drivers side area where the CV's attach there is a cover that seems to be made of mag not aluminum and giving me the most trouble. It's out of the car, is it out of the question to bead blast it? Would it risk getting stuff inside?

[catuck]

Just a quick tip - make sure you plug the vent hole before washing. You don't want any water rusting your gears!

[Zeke]

Originally posted by Craig Roche
Thanks all for the reply! I'm trying to make it look as good as yours does Ryan. I've been silently checking your progress, very very nice I must say!!!! Seems like the drivers side area where the CV's attach there is a cover that seems to be made of mag not aluminum and giving me the most trouble. It's out of the car, is it out of the question to bead blast it? Would it risk getting stuff inside?

Only bead blast empty cases and leave the seals in to protect thier machined mating surface. For the same reason, bolt things together so you don't blast any machined sufaces. Separate everything and pull the old seals after basting and wash up real good.

Mag cases just look dull gray anyway. You can srub them down with hot water, licquid detergent and some solvent of your choice. Use gas, lacquer thinner, benezene, acetone, paint thinner,etc. It all warms up and evaporates, so get out doors. I finished my 901 tranny up with acid. Brightened it up real purdy. Carefull, it eats the metal before your eyes (which should be covered). Rinse with lots of water to flush the acid off the metal immediately.

Cheat. Get a can of dull silver paint and thin it out and use it like a stain. Put a little black in it if it's too bright.

[surflvr911sc]

Thanks Craig, the trans looked a lot better in the pictures than it was. Like the other guys said, I wouldn't blast it unless you are doing a full teardown.

I would like someone to confirm what the side plate is made of. I’m pretty sure that it’s aluminum, that area needs the strength. Good Luck!

[jeff m]

Aluminiun - hydrofloric acid
Apply with a good spray pattern from bottom up.
Rinse from top down.
This applies to all aluminium cleaning.

An aerosol of alum wheel cleaner from pep boys will do a decent job for those without access to acid. Two or three goes though.

Jeff