Breaking free old frozen transmissions: Tricks?

[Kilroy]

I have this 49 Merc transmission that I'd like to see what I can salvage from it... It didn't look bad on the outside but the inside is frozen with some combination of rust and old grease. It's been soaking in penetrating oil and Posphoric acid in rotation for a couple days now and it's getting pretty clean inside, but unless it gets to where I can rotate the gears etc, it's probably all just wasted effort, so I'm starting to think maybe I've lost this one...

Are there any tricks to getting these old trans free enough to break apart? Take it to get hot tanked? Some chemical I haven't thought of? Or just a crap ton of torching? Can you just dump the whole thing is a tub and electrolysis its butt?

This one has an overdrive attached and I'd really like to get that off so I can attack both separately, but it won't budge...

[fordwife]

I have always drained the grease and soaked them in diesel oil. Give it more time to soak, like a week or more.

[slowforty]

acetone and auto trans fluid in a 50/50 mix works well too

[tubman]

Get as much grease and oil out of it as you can and then fill it with Evaporust or similar to attack the rust. Maybe a couple of two or three day soaks.

[rbone]

The other thing that will help would be to put some sort of torque on the input shaft and/or output shaft while it is soaking. You would need to make up something with a cheater bar and a weight or similar and have the tranny firmly in a large vice. On frozen engines, I have found that consistent pressure helps the motor free up a little easier. Would think the same would hold true for a transmission.

[RalphM]

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I’ve soaked them and then used a long brass drift and tap the gears back and forth till they free up.

[Aarongriffey]

I would not say acetone and ATF works well. I would say,”works Better than anything else”.
As SLow Forty says, “mix it 50/50”. It tends to separate so shake it up every few hours.
Add some MEK to the mix if you have some. Methyl Ethel Keatone.

[Viv W]

Water works better than any penetrating oil, put the Tranny in a drum of water and leave it to soak , 3 to 4 weeks if rust is not too bad, but up to 3 months if really rusted solid. The rust is caused by water and water will dissolve the rust and penetrate better than anything else on earth. I have used this method on several motors, the latest was a Model A that had sat in the rain for 10 years with no spark plugs in the head, it took 6 weeks and some gentle persuasion with a 4lb hammer and block of wood. I got all the pistons and valve train out and even got the rings off the pistons without breaking a single ring.
If you don't believe me, try it .

[tobby]

always liker ATF and diesel fuel or kerosene, acetone evaporates to fast. acetone is too expensive. and kerosene, a small amount spreads everywhere

[Lanny]

Originally Posted by Aarongriffey

I would not say acetone and ATF works well. I would say,”works Better than anything else”.
As SLow Forty says, “mix it 50/50”. It tends to separate so shake it up every few hours.
Add some MEK to the mix if you have some. Methyl Ethel Keatone.

===============================================


I've been experimenting with acetone/trans fluid 50-50 mix for over
two years now.
I've had this RUSTY nut/bolt that holds two pieces of trailer hitch
metal together, did I mention it's RUSTY.

For the first couple months or more, I always kept adding the acetone
a couple times a day, because it does evaporate very fast.
Every few days, I would take the nut/bolt out and try to get it loose
with 1/2 inch drive tools, after a couple months, that got REAL OLD.

Screw the acetone, what a joke... So, for 2 years or more now, it has
been soaking in just the trans fluid. I take it out about once a month
and try the 1/2" drive tools, and still NOT a chance in heck is it budging.

If you are getting rusty stuff loose with a 50-50 mix of that crap. THEN
your stuff is Not really very rusty, and a good penetrating spray would
have worked better for you, and a lot less hassle then the mix crap.

I'm going to experiment with "the soaking it in water trick" for a
month or two, and see how that works, wish me luck.

Click on pic to Enlarge...

[RalphM]

There comes a point in Rustdom where no amount of snake oil will break it free.

[Kilroy]

Originally Posted by Lanny

===============================================


I've been experimenting with acetone/trans fluid 50-50 mix for over
two years now.
I've had this RUSTY nut/bolt that holds two pieces of trailer hitch
metal together, did I mention it's RUSTY.

For the first couple months or more, I always kept adding the acetone
a couple times a day, because it does evaporate very fast.
Every few days, I would take the nut/bolt out and try to get it loose
with 1/2 inch drive tools, after a couple months, that got REAL OLD.

Screw the acetone, what a joke... So, for 2 years or more now, it has
been soaking in just the trans fluid. I take it out about once a month
and try the 1/2" drive tools, and still NOT a chance in heck is it budging.

If you are getting rusty stuff loose with a 50-50 mix of that crap. THEN
your stuff is Not really very rusty, and a good penetrating spray would
have worked better for you, and a lot less hassle then the mix crap.

I'm going to experiment with "the soaking it in water trick" for a
month or two, and see how that works, wish me luck.

Click on pic to Enlarge...

Soaking that in water is just going to make a nice place for a fish to hide... I think I'd be more inclined to see what Molasses does to it. I mean, if you're thinking 2 months anyway.

That said, I don't think 'unscrewing that' is in any kind of realistic future... That looks like no matter how much rust you get off of it, it's still going to be a torch/cut job.

But I bet 2 months in a molasses bath might make it a different color at least.

[tubman]

Lanny,

As a last resort, try the soak in Evaporust I suggested earlier. I think you can buy a quart at Advanced Auto or some such for less than $10. That should be more than enough to immerse the rusty part. Just another test procedure. (After soaking it in water, it'll probably need this.)

If it doesn't work, I'll pay for the Evaporust next time I see you.

Denny

[Lanny]

Originally Posted by tubman

Lanny,

As a last resort, try the soak in Evaporust I suggested earlier. I think you can buy a quart at Advanced Auto or some such for less than $10. That should be more than enough to immerse the rusty part. Just another test procedure. (After soaking it in water, it'll probably need this.)

If it doesn't work, I'll pay for the Evaporust next time I see you.

Denny

==============================================


hey Denny, how ya doin...
I used this old very Rusty nut and bolt just for the experiment, to see
if the "50-50 mix" was worth a hoot to free up very rusty stuff. It Isn't.

Here is a picture of a very rusty little hinge that I had placed in the mix
back a couple years ago too. I pounded a screw driver into one end of it
this morning, and as you can see, the little hinge would NOT budge loose.

Click on pix to Enlarge

[Lanny]

Originally Posted by Kilroy

Soaking that in water is just going to make a nice place for a fish to hide... I think I'd be more inclined to see what Molasses does to it. I mean, if you're thinking 2 months anyway.

That said, I don't think 'unscrewing that' is in any kind of realistic future... That looks like no matter how much rust you get off of it, it's still going to be a torch/cut job.

But I bet 2 months in a molasses bath might make it a different color at least.

===============================================

I said in my post, I was doing an EXPERIMENT.

Why don't you try molasses in your transmission then ?
I've experimented with molasses and that eats into certain metals.
Vinegar works better than molasses, but it sounds like Denny has
been Experimenting with Evaporust, and sounds like it works good.



.

[tubman]

Molasses is an acid, and if you let it go too long, it will harm the surface of the metal. There was a thread on the H.A.M.B. a few years back where a guy soaked a block in molasses for an undefined period. When he pulled it out, the whole engine (including the deck) was deeply pitted to the point of being ruined. If you are going to use molasses CHECK IT OFTEN.

I had an old set of Craftsman automatically adjustable pliers (not a vice-grip, but not plain pliers either) that had dropped in a damp corner in my shop for several years. They were a mass of rust and frozen solid. A couple of days in Evaporust and a little 3-in-1 oil and they looked and worked like new (which still isn't very good).

Unlike acids, Evaporust and it's clones will not harm ferrous metal. It's kind of expensive. so I have been trying for years to find out exactly what it is with not luck. It works by chelation which I am not enough of a chemist to fully understand.

[Kilroy]

Originally Posted by Lanny

===============================================

I said in my post, I was doing an EXPERIMENT.

Why don't you try molasses in your transmission then ?
I've experimented with molasses and that eats into certain metals.
Vinegar works better than molasses, but it sounds like Denny has
been Experimenting with Evaporust, and sounds like it works good.



.

Because it eats metal... But that wouldn't matter on that bolt and nut because it's so far gone anyway... Hence, why I suggested it...

It seemed like a better EXPERIMENT... Since simple water is pretty obviously not going to have much effect on anything other than surface rust.

[Lanny]

Denny (tubman), I did some checking on the Evaporust today, and
the store I called said that Evaoprust is a Water-Based product.

They told me that buyers keep coming back with praise for how it works.



.

[Lanny]

Here is a short comparison video of a few different rust remover products.
Take a look.
https://www.youtube.com/watch?v=CQMzUkEKaBo



.

[rotorwrench]

Usually the transmissions have enough old gear lube in them to keep them from rusting up too bad. It must have set out in the weather for too long. The input should turn with the cluster gear if it's in neutral. Both shift arms have to be in mid position. If the thing has overdrive then it may have a problem in the planetary. If that's the case, it will have to come apart to get any final drive movement.

A lot of the gears and the synchronizer are usable in the earlier Ford transmissions if they aren't ruined. The mainshaft is different whether its a standard drive or overdrive since it's the longer open drive type

[RalphM]

I just had a stuck transmission given to me. Open drive, 40’s ish, I haven’t uncovered the serial number yet.
I had a gallon and a half of evaporust laying around, used, so thought I’d experiment. Instructions say 30 min for light rust, overnight for more. I’m going to let it sit for a few days before I check it.

[fordor41]

for small stuff, nuts and bolts etc I've used muriatic acid. can get it at any home center. just don't soak things too long.

[F-ONE]

Originally Posted by fordor41

for small stuff, nuts and bolts etc I've used muriatic acid. can get it at any home center. just don't soak things too long.

Anything I have personally used muriatic acid on was eventually destroyed. I was careful. I cleaned and neutralized. The stuff looked like a million dollars.....

Until it crumbled to pieces.

I found a possible reason for this. The stuff is hot! Another thing is it can produce chlorine gas.

It seems muriatic chlorinates the steel. In other words it impregnates chlorine into the good steel at a microscopic level. Chlorine is an oxidizer.

Paint or even grease may prolong something treated with it because it seals out oxygen. Eventually though....it will rust.
Any untreated surface may look great but will turn to poo poo rather quickly.

[tubman]

Originally Posted by RalphM

I just had a stuck transmission given to me. Open drive, 40’s ish, I haven’t uncovered the serial number yet.
I had a gallon and a half of evaporust laying around, used, so thought I’d experiment. Instructions say 30 min for light rust, overnight for more. I’m going to let it sit for a few days before I check it.

I have used Evaporust quite often and like it a lot. I have never used it for something like this, though, and will be quite interested in how this turns out. From my experience, it will probably take several sessions, because the stuff does "wear out".

I will emphasize again that this stuff is not an acid, and therefore doesn't deteriorate he metal in any way. Acid will eat rust, but unfortunately adversely effects metal. It's just a matter of degree.

[RalphM]

I almost forgot about the transmission, it’s been a week. I just drained it out started to clean it but it’s still pretty stuck so back in the solution it goes. I have hopes of getting this one free because the gears and syncro’s look pretty nice.

[JSeery]

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Originally Posted by RalphM

I almost forgot about the transmission, it’s been a week. I just drained it out started to clean it but it’s still pretty stuck so back in the solution it goes. I have hopes of getting this one free because the gears and syncro’s look pretty nice.

I think a clean new solution would make a world of difference over reusing it.

[RalphM]

Your probably correct, I did add about 1/2 gallon of new evaporust to it today. It’s just the stuff is expensive, at least here. I think I paid about $40 for two gallons. I see Home Depot here has a 5 gal bucket for $76.

[tubman]

For stuff like this, I use something called "Rust-911". It's a concentrate, so it's a lot cheaper than Evaporust. In the long run, however, I don't think it does quite as good a job as Evaporust, but for something like this, the savings are worth it.

Here's a link : https://www.rust911.com/rust911-ultr...free-shipping/.

It looks like you are getting pretty good results with that transmission.

[Mart]

I'm going to be blunt here. I think you may be wasting your time. De-rusting something like a gearbox casing or old crescent wrench may be worthwhile but when it comes to precision engineered parts like gears and synchros you must surely be left with pits where the rust has eaten in.
Not trying to be a killjoy, but realistic about the potential outcome.
I hope you prove my conjecture wrong and have a good usable set of gears, but I don't believe that outcome is guaranteed.
Mart.

[Bored&Stroked]

In looking at the last transmission pictures, it does not appear that those gears will be usable - you can see heavy rust pitting on everything. I'm with Mart - rust pitting on precision machined parts - will ruin most of them.

[cas3]

and, while i am no engineer, i have always been told that the case hardening on the gear is not too deep, so it goes away with the layer of rust leaving you with a soft pitted gear. fact or fiction...take your pick

[tubman]

I know you guys are right, but I would like to see him complete the process just to see how well it works. The gears are probably toast, but the synchronizers look pretty good. I would like to see this taken to the point where we see if he can get that transmission to the point where he can disassemble it.

[rotorwrench]

I won't tell anyone not to do something but I will say that every rust pit is a potential stress riser for cracks. Cracks can lead to tooth separation.

The old ford transmission cases are sensitive around the front bore that the countershaft fits into. Any rust pits in that area won't make it stronger. The thrust surface on the back has to be smooth and thick enough to act as a thrust surface in conjunction with the thrust washer that goes in there.

[tubman]

To me, it's more about the Evaporust than the transmission.

[cas3]

evapo rust is a good thing, no question about that. i just hate paying for it! agree 911 is good too, but sightly weaker/slower. its all just another "if ya wanna dance, you gotta pay the fiddler"

[JSeery]

Originally Posted by tubman

To me, it's more about the Evaporust than the transmission.

I agree, was interested in seeing the results! I have been using 911 because of the cost difference.

[RalphM]

Kilroy,
Any luck with your transmission?

I’ve only been at the evaporust for two weeks, started with a used batch. But I’m impressed at how clean it is getting after two weeks. Still not free to move, but I think I’ll invest in some brand new if Evaporust and see how much further I can clean it. I lightly wire brushed the part of the gears I could get to and there is not any deep pitting in them.
So I’m still hoping that some of this might be salvageable.
Ralph
My really good pictures won’t load this is the best I can do

[JSeery]

Looking better! If you want any additional photos posted you can email them to me: [email protected]

[JSeery]

Two additional photos Ralph wanted posted.

[Zeke3]

Impressive progress.

[Lanny]

Before and After comparison pix.

Click on Pix to Enlarge

[cas3]

well, for me the pics would not enlarge. never had that before! but anyhoo, does the tranny turn yet? sure looks better!

[JSeery]

Originally Posted by cas3

well, for me the pics would not enlarge.

Same here. Ok, they are like 8 Kb files, so they are far to small to enlarge.

[Clem Clement]

I put a tranny in a tub of cheap white vinegar. About a month got most of the rust out

[tubman]

Vinegar is an acid, albeit a weak one. It will destroy metal while Evaporust (and it's clones) work by "chellation", which will not eat the metal.