Narve N

38 Imperial gearbox with rusted gears - help appreciated

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Posted (edited)

My good looking 38 Imperial gearbox with OD that I bought 15 years ago, turned out to having been quarter filled with water and no oil when I recently looked into it. Horror rust scenes was unveiling. Gears otherwise look excellent and probably the fault is all mine as I had it in a chassis standing outside for a year. Anyone ever tried to derust something like this e.g. submerging it in a hot tank, or do you by any chance know a vendor with gears laying around? The great thing about 38 Imperial is the use of a 11" clutch and is also the last year with manual OD, so the intention is to use this transmission in my 8-cylinder Special project based on a 1929 Series 65 parts car.

1904 23 Rust i 38 girkasse CT-S (2).jpg

1904 23 Rust i 38 girkasse CT-S (3).jpg

Edited by Narve N
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34 minutes ago, Tinindian said:

I would try molasses and water.  It works great and is totally biodegradable.

You beat me to it. I was going to suggest the same thing.

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Good suggestion, I am afraid that some of the hot tank stuff could attack any softer metals inside the gearbox. I likely could fill it up with the molasses mix and stir it around with a stick once a day. How is the procedure to remove the molasses, use pressure washer?

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They don't look very rusty to me. That appears to be mostly dirt and watery muck. Clean it out and have another look.

 

If you use molasses, expect to leave it in for at least a month. Cover it too, because all the local bugs would like a drink of molasses but they can't swim once they dive in.

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Rust can be removed by electrolysis, all you need is a plastic bucket, battery charger, steel electrodes and washing soda. Details can be found with a web search.

 

Suggest you take the box apart and carefully inspect the bearings and replace if necessary. Clean everything up and reassemble. It could be a wire brush is all you need to take off the rust.

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Were it mine, I would high pressure wash it, (at the car wash) and submerge it in EVAP-O- RUST.

IT  WILL NOT HARM SOFT METAL. And it is also biodegradable

Worked wonders on my '40 Buick cooling system..

Mike in Colorado

 

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If you do the molasses and water thing.

You would need degreasing first. (Pressure wash with detergent)

The barrier of any lubricant (or paint) will block the molasses.

 

FLYERs suggestion seems feasible to me as well.

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I am hearing a lot about Evaporust - that is a good looking gear-case inside - just need to de-muck it and get whatever you need handled to get it installed in the car.

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Evaporust works great if you can completely submerge the parts. I would fill it completely.

 

You don't want parts sticking above the level of the evaporust. That seems to cause rust right at the point where air is available.

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I appreciate all good suggestions. Another source also mentioned that I could be lucky and there might have been just enough oil left on the bearings to save them from the attack of water, so I could just try to clean everything as best as possible and run the transmission as is - to check my luck. Taking it off the car again if it doesn't work is a small job compared to taking it all apart for full derusting.

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Posted (edited)

Flush it with with kerosene, spin it around for a while with an electric motor with the thing filled with the kerosene, then power wash it out as good as you can. Fill with evapo rust, place it on a hot plate on low for a long time turning it every so often.......let it sit for a week or longer with the evapo rust and the low heat......be sure you can't get any fires going.....keep it safe. After the evapo rust treatment, rinse it a few times with clean water, then back to the kerosene. Be sure to get ALL the water out of it. Then you can eyeball it, as it doesn't look like a lost cause, you can probably fill it with gear oil and run it with a bit of luck. It would be best to take it apart........but the above method is fine to inspect it. It will probably be ok. 

Edited by edinmass (see edit history)
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Ed, I've never used Evaporust. Will that attack the bearing surfaces, or the brass/bronze bushings and thrust washers?

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Evapo rust will NOT touch brass, bronze, or any non ferrous metal. Gasket and leather seal as well as felt seal safe. It will remove all the rust, holding it in suspension. Just be sure to let it work, and flush it well. Most of the gears are case hardened. It will be fine, as long as there isn’t too much pitting. 

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1 hour ago, edinmass said:

Evapo rust will NOT touch brass, bronze, or any non ferrous metal. Gasket and leather seal as well as felt seal safe. It will remove all the rust, holding it in suspension. Just be sure to let it work, and flush it well. Most of the gears are case hardened. It will be fine, as long as there isn’t too much pitting. 

 

Thanks ed, I'll have to get some of that and try it.

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Posted (edited)

I have been watching this topic with  interest as I have prolbems with my overdrive

Just wondering if anybody knows of  any source of parts for these overdrives? 

I'm getting ready to remove mine from a 1937 sedan , it has bronze particles in the oil and has become noisy. I will most likely need to replace the large bush and a few of the small gears.

So I will need to find a replacement  or the specs to have a new one turned up.

Any information would be helpful! 

Thanks

Edited by aunty norm (see edit history)

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Evapo Rust available at Local Tractor Supply ,

grey plastic gallon container with yellow label ,

about $20-$22 /gal.

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Posted (edited)
On 5/26/2019 at 12:31 PM, aunty norm said:

I will most likely need to replace the large bush and a few of the small gears.

I had to replace the planetary gears, or at least the bearings and pins. The full complement needle rollers in them had worn barrel shaped and square. Just after I had them rebuilt at great expense, I found a planetary gear set NOS. Humph!

 

Which model do you have? The C15 OD is different to the C14 and C16.

restorecarsclassifieds.com/wiki/show_pdf.pdf?n=4849

restorecarsclassifieds.com/wiki/show_pdf.pdf?n=4850

Edited by Spinneyhill (see edit history)

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Posted (edited)

Hi! Spinneyhill

Not sure of the exact year and model.

But the casing has R6-1,  T86 - 1P ,W.G. DIv.           11  13  36,

It also had some numbers on top of the gearbox , SL2336

Plus it has a mechanic drop down, not electrical.

Hope this makes sense!  

I'm away at present but will remove the overdrive as soon as I get home! I have a club rally in a couple of months, not much time to repair the box!

20170219_122334.jpg

20170219_122245.jpg

Edited by aunty norm (see edit history)

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T86-1P was used in the '37 Chrysler C14, Imp; C16, Roy; and the '37 DeSoto.

 

Electrical kick-down came in 1939.

 

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