Cleaning 1931 Transmission

I have a 1931 Reo Royale transmission that must have 80 year old oil in it . I had to use a screw driver so it would come out the drain plug . It came out worse than molasses . How should I clean the oil gunk and residue out of the transmission ? The car is not operational . Thanks

I would disassemble the transmission completely to clean it up with any good degreaser like Simple Green and refurbish the guts.

Or you could fill it with kerosene and let it set. If it leaks out you could dunk it in a pail of kerosene. By the time you are ready to work on it maybe the old grease will dissolve.

If it is still on the car you could fill with kerosene and let it run at idle, in gear, with the back wheels jacked up for 15 minutes then drain it out. This will not hurt anything if it is not under load.

That oil is undoubtedly 600W.

You can thank that oil for keeping your transmission serviceable so long.

Not only that but it causes enough drag in the gears which makes it less of a crash box.

A mechanic told me to put a little automatic transmission oil in the bottom of the transmission . Since it is a light oil it will help break down the heavy oil . I like the kerosene idea but where it is stored they are not thrilled about kerosene as it could catch fire . The mechanic is worried about using varsol as it could affect the old seals ?

There are likely no elastomeric seals in the transmission, so there is no need to be concerned about damage.

There is however a chance that it has oil circulating passages that will not be flushed out with anything put in to thin the existing lube ( which is probably old 600W as suggested). Some transmissions of the era have a hole between the gear teeth to let turning gears act as a pump to circulate the lube. Also the unsealed bearings often are designed for lube to pass thru them then down thru a return hole to the bottom of the case. Either of these can be plugged by solidified lube and stop proper lubrication. Only really safe course is as keiser31 said, disassemble and clean. I am with barry22, probably no true seals in the modern sense.

By the way, 600W is still available and does work well.

You could also try putting a heat lamp or 500 watt halogen shop light on it for a couple of hours, then drain. That type of oil thins out quite a bit when it gets hot.

I am going to take everyone's suggestion . i will heat it up with light . Try a thin oil and if I am brave enough try keiser31 suggestion and take it apart .

What do you mean non operational?

The car has not run for 50 years ?

^ To me that's a good thing. 50 years less wear on it........

If it has not run in 50 years why are you worrying about the trans oil?

I will suggest using only a petroleum product to dilute the old grease in the trans.

If you do take the trans apart, I will again recommend using only a petroleum based solvent or cleaner.

The 'simple-green' and other citrus acid type of cleaners strip all the petroleum off the ferrous metals and other metals and if

the items are not immediately soaked in some form of petroleum product they WILL RUST within an hour or two.

I've learned this the hard way using a big upright hot water/detergent cleaning machine.. it's like a big dishwasher, uses 200* water with

what ever soap/detergent you add in.

The parts just about rust before your eyes when you blow off the residual water with an air hose, set the parts aside to do the next part or two.

Then you go to pick up the still warm to the touch steel bearings, steel shaft or other item and it already has surface rust forming. The soft parts. like an aluminum case will form a thick 'fuzz' on the machined surfaces.

So, if you do use a citrus-based cleaner, put EVERY part immediately into a bucket of ATF, motor oil or something, and brush a coating of similar ATF or oil on any large items, making sure to get into ALL areas.

I just about destroyed a transmission with an aluminum case using a recommended citrus based cleaner in this parts washer.

I then drained and flushed the parts washer tank, and put in fresh water with a product used by automatic transmission repair shops. This product leaves a thin, white coating on everything, which provides a protective layer against immediate oxidation. The coating wipes off with an ATF soaked rag, or in a bath of ATF.

I've also seen the engine compartment of a few vehicles a mass of rust and grey fuzz from being washed with a citrus based cleaner, and not rinsed well enough. The owner had to replace a LOT of fuel injection lines and fittings [diesel injection steel lines] and most of the brake lines and a lot of electrical components..

Too clean can be a big problem. Internal components that run in oil need to be kept covered in oil somehow.

GLong