Technical Anyone ever sandblasted a 4-sp case???

My ST-10 has been stored under my bench for the last 20-25 years. Therefore it has a lot of rust on the case (see pic below). The trans has all the innards in it.

I'm thinking of taping off the input shaft and output yoke and blasting the outside; then painting same color as engine and bellhousing.

1. Anyone ever blasted a case?
2. What media did you use or recommend?

NOTE: when I say "sandblasting" what I really mean is using an appropriate media. Also I'll remove the shifter and linkage.

ALSO NOTE: not that anyone cares but this trans has a 26 spline input shaft with 3 rings (2.64:1 first gear) with the # 13-04-065-904 on the case. According to my research the 904 at the end of that number denotes a nodular iron case.

ANOTHER NOTE: also not that anyone cares, this trans is slated to go in a full fendered '31 sedan behind a fresh nailhead (401 or 425; whichever turns out to be in better condition will get rebuilt).

3. Any reason I can't remove the input shaft and clean it up with a soft wire wheel on an angle grinder?

 

I just used solvent then Simple Green (straight) on my Muncie and left it at that.
That is my new Richmond Super T-10 next to it.


You can do your best wire brushing then you might consider leaving the tailhousing natural if it's aluminum and match painting the main case with something like a light gray "cast iron" paint, a few different brands out there, I painted my cast iron master cylinder with it and am pleased with the outcome.

 

Baking Soda blast it [as is] with a yoke on the output.

 

Looks like you've got what was known as the "Brute Strength" version, with the nodular iron case.
Sold over the counter only and at speed shops, never factory installed by GM.
I would not sand or media blast it unless you are prepared to clean the interior of each section.....it is very hard to get something like this sealed up tight to blast media.
Maybe soda blasting would be the ticket, since it could be washed out easily if there is a blasting leak.

Don't forget that vent, right above the side cover. Don't blasting into the bearing collar tube.

If you are going to try to remove the input shaft, trans must be held vertical, tail up, when you do as there is a set of loose needle roller bearings in a cup machined on the back end of the input shaft ( a dozen or so, about 1/2" long x 1/4"" diameter ), the pilot nose of the main shaft rides in that set of rollers(just like how the other end of the input shaft fits into the pilot bushing/bearing in the crank.)

I'd suggest you look up some pictures and exploded views so you know what to expect behind that front bearing collar.

 

I wouldn't blast with any media, unless you're doing a complete rebuild. It will either get into the seals or destroy the seals.
Good old chemicals. Evaporust or Naval jelly. Engine degreaser or simple green for crud.

 

Since it’s going behind a fresh nail head,,,,why not disassemble and check it out good .
It’s only a set of gaskets,,,,,,and you could clean it very easy while apart .
Some gunk engine spray,,,,,hose it off,,,,,and maybe some Scotchbrite pads and a good hand wash,,,,good to paint then .
It really looks more dirty than rusty,,,,,I don’t think it needs blasting .
Should be a good trans after gaskets and seals .

My old T10 looked much worse than that,,,,,I didn’t take any before pics,,,,but these are after,,,not too bad,,,,,not a terrible amount of work either .

Tommy

 

You can sandblast anything, right down to clean metal IF your willing to protect the part and clean it up after blasting.
I've blasted tractors motor transmission and rear end but you must clean up afterwards and protect the part from sand infiltration.

 

In my experience media is magical and gets EVERYWHERE. I’m on team don’t do it unless you plane to completely disassemble it for cleaning. It doesn’t seem like it would be to bad to clean up by hand.

 

OK. Thanks for the input. It looks like I'll forget the blasting idea. Although if I decide to empty the case for inspection/repair I might do it then.

Below are some pix I took after using the wire wheel/angle grinder on the numbers. I should be able to get most of the case looking that good, although I'll have to use something else to get down into the nooks and crannies (which is why I contemplated blasting).

I've googled these numbers but don't find any information on date codes that matches up with any of my numbers. Do any of you see a date code here? Could the bottom number in the last pic be it? It may not have a date code based on the Ericnova72 response. OR, because it says W. G. DIV was it actually a factory transmission?

 

I believe D-14-68 is April 14 1969 but others may no better.

 

Edit: 1968

 

Denny - that Muncie looks great. Of course, being all aluminum, it doesn't need paint.

Tommy - I hope mine comes out as good as yours did. Based on the new side cover gasket I see it looks like you disassembled yours.

 

That's what I thought but needed someone more knowledgeable than me to confirm. And I've been trying to decide if that's an 8 or a 9. I guess it really doesn't matter which though.

 

advice from a friend? I would not blast it.
Get you one of those wire brushes that you can put on a drill or a cup brush for your angle grinder and clean it up. The hit it with rustoleum primer for rusty metal.

or out of pure desparation make a trip to Browning with it. The missus will cook and we can make a day of it. I don't mind doing the grunt work for ya.

 

That right there sounds like "an offer I can't refuse" whether I bring the trans or not.

 

Well I probably anint goin no where.
The house is still a mess and we are still living down stairs but we are not ashamed of that. LOL You are welcome any time.

 

Years ago, I used a low-pressure, siphon-type media blaster to remove the rust from a cast-iron T-10. I can't remember if I used sand or glass. The media was in an open bucket/w suction tube inserted into the bucket. The transmission cleaned up nicely, and I think I clear-coated it afterwards. I did not drain the transmission, which did not leak before/after blasting. I wasn't obsessed with media getting into the transmission because I knew it needed work, particularly 3rd-gear synchro. I sold the transmission at a swap meet for $150. The buyer was happy to get it, and I did tell him that the transmission needed a synchro.

Depending on the type of blaster you use, I think it's possible to do without media entering the transmission. What I used was an inexpensive Harbor Tool setup, intended for the hobbyist, not for industrial applications, and was very controllable. Working up close confines the area that's being cleaned, which was also necessary due to low pressure and choice of media, kind of like using an airbrush instead of a gun. The siphon hose did have a tendency to clog, requiring removal and insertion of the hose a number of times.

 

I guess I'm a little selective when it comes to painting transmissions, not that I've ever done it.
It mostly stems from seeing those "rebuild" shop jobs where they always used that flashy aluminum paint on EVERYTHING.
I'd cringe anytime I saw a transmission painted with it.

 

I think that shops use whatever is cheapest for paint. I took some bare corvette heads to a shop for a 3 angle valve job once. The shop did good work and I did not have access to a valve machine at the time. I told them to please not paint the head and for whatever reason the machinist painted them anyway. beautiful Ford blue. Nice paint job but not for my chebby orange motor. LOL

I have a younger friend that rebuilt a T-350 when he was a kid (like 10 or 12 years old). Did a damned good job on it, he has used it in several cars over the years and it has not been back apart. For whatever reason he bought good paint and painted it in starts and stripes. The tranny sits on a shelf in his shop now still has that '70s paint job in it, Ugly as butt in my mind but he likes it.

 

Denny, you can take it to the bank that there will be NO aluminum paint on this trans or any others that I own. I haven't actually chosen the engine and body color for this car but the trans color will be the same as the engine. I've been thinking about one shade of green for the sheet metal and another green for the hard parts. Maybe. Maybe not...

 

By-the-way; the tail housing and side cover on this trans are both cast iron. I thought these should be aluminum on a T-10. Is this not true for the T-10 Ericnova72 referred to?

 

Mike ,
If yours is the Brute,,,they were built heavy to take some serious abuse,,,,,,most of them really caught a hard way to go ,,,LoL .
Mine is iron main case and aluminum cover and tail housing.

Yes,,,,I went completely through mine,,,with several new gears and a new pilot as well .
I had to switch the pilot because I couldn’t find the correct cluster,,,,,LoL,,,,lucky me .

Tommy

 

Tommy,

You'll note in my pic and yours the shape is almost identical, but not quite. Mine has a bulge on the top where yours is pretty much flat.





Anyway, I've been talking this evening to my buddy who is a transmission guru. After the holidays when we've all got cabin fever we're going to get together, pull the side cover, and decide whether we need to pull it apart for rebuild.

I'll be cleaning it between now and then as well as I can with wire wheels and wire brushes. If it needs to come apart that'll give me the opportunity to clean it even better then.

So, when you had yours apart, how did you clean up the empty case?

 

Mike ,

Yeah,,,,I’m sure yours has a few upgrades from mine,,,,,mine is a 62 model ,,,LoL.
There isn’t a vent on mine like there is on yours also .

Tommy

 

Not sure if the Brute had aluminum or iron tail housing, or of both were available....but the 26 spline input and iron case was never an OEM factory option, so it isn't any stock trans.

Now, it could be a shop built or home built combination of ST-input and replacement Brute T-10 case.....what size output spline is in it?? ST-10 would be 32 spline

That 1968 time frame was right about the time the Super T Brute was introduced IIRC.

Been a long time since I've seen one.

About the bump on the top of the case, the ST-10 has a larger, wider bump that isn't as pronounced looking as the photo Desoto291Hemi posted of the early iron case.

 

The GM Super T-10 was the OEM replacement when the Muncie era ended, about 1974.
I bought a freshened up ST-10 for my bracket racer around 1975 or 1976.

 

Folks; I've just self educated myself. While I was looking on-line for wire cups I saw wire end brushes. Perhaps that's what P-N-B meant but I just didn't catch it. I'd never heard of them so looked further. Maybe that's the solution for getting down into those tight corners and crevasses. Anyone use them? Got any suggestions? I'm thinking in a cordless variable speed drill. What say ye? Some are Stainless Steel and some are not. Any advantage or disadvantage to SS?

 

The stainless brushes will not get rusty when sitting around not in use would be the only advantage I'm aware of

 

I once sandblasted a fresh rebuilt White 6cyl. for my Halftrack. I spent days tracing all the gaskets to steel and torch cut exact covers for every hole in the block, silicone and bolted down to seal perfect. Engine ran a few hours before a rod knock started. You guessed it, sand on the bearing shell. No way for it to get in there...but it did. never again

 

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