Cleaning tips

I was looking at my transmission housing yesterday and marveling at how hard 70 years of gunk is to remove. I started off by spraying a cleaner like Purple Power on it then using the pressure washer. I thought I was done but after it dried I could see spots I missed so I pressure washed it again without noticeable improvement. I scraped at some of it with a screwdriver before letting it soak a few days in the parts washer and have been scrubbing it with wire wheels, scotch brite pads and wire toothbrushes. It still shows dirt in spots when I let it dry. I can’t get into the tighter corners with a wire wheel.

Used Easy Off on some other parts and got similar results although it didn’t take as quite as much effort. I did notice more corrosion after using the Easy Off.

I have been tempted to do some of this in the sandblaster but my cabinet is a little small for a transmission and it could be a challenge to get all of the media out of the transmission when done.

The idea is to get it worth painting. I wanted to see what kind of cleaning tips a thread like this might produce. Not just for the greasy chunks but for frame restoration/paint prep as well.

Do you have access to anyone with a hot tank, maybe a local engine rebuilder or machine shop? The sodium hydroxide/caustic based cleaners and heat seem to do the best job of dislodging stubborn crud. They actually emulsify it and make it water soluble.

But - perseverence, poking with screwdrivers (popsicle sticks get into rounded corners) and just going over it again and again work too.

GMWillys has a lot of history and experience with getting things clean over at the Rust Ranch - he'll drop in here with comments fairly soon I'm sure.

Larrbeard hit on the head....
A hot tank is the best, they will put it in overnight usually and let it bake and it will come out like a brand new case!!!

I have a large parts washer filled with mineral spirits. I go after it with screw drivers and scrapers, let it soak in the spirits for a few days and then go after it with a stiff nylon brush and blow it off with air. It is hard to beat mineral spirits when you are dissolving grease.

At the rust ranch, I use Horrible Freight nylon abrasive brushes on everything. They work good on frames, cast iron components, and sheet metal. I'm a big fan of the brushes, and buy them by the gross. The brushes are run with a 3/8" variable speed drill. It's a bit time consuming, but the metal surface is ready for paint after running prep-sol over it before spraying primer.

That’s better than sand blasting it gm!!!
It doesn’t warp