Gear Teeth Rust

[gungeey]

I got this set out of a 66k car about 25yrs ago and have been lugging it around with me from house to house since. I plan on giving it a new oil seal and installing it in a car. Weather took a little nibble out of it as seen below. I can crocus cloth the rust, immerse it in vinegar, or make pretend I never saw anything.

 

Any experienced thought? Thanks, Steve

[JFranklin]

I guess it all depends on what it is going in and its intended use. It will drive a car down the road and might not make any perceptable noise.

[NailheadBob]

Possibly Evapo-Rust may help you.

 

Bob

[Turbinator]

If it is rust removal I’d start with Naval jelly. Tape and or wrap up everything you don’t want Naval jelly to get on.. Rustoleum Aircraft remover old chemical make up will get it off. The pink color Citrus stripper is surprisingly effect and easy to get. After that the non woven fabric abrasive polisher come in many different sizes and shapes that are mounted on shafts. I’m sure the abrasive cloth will not take off any metal. Lastly Cratex rubber abrasives come in different shapes and sizes used in a drill motor or Dremel.

[RivNut]

Molasses and water mixed 1:9.  If you can immerse the part. You probably need to know if any pitting has occurred. What's the gear ratio?

[1965rivgs]

Steve,

  I dont think crocus cloth is going to do much to that degree of corrosion. If you are careful and orient the corroded section of the ring gear down so any rinsing technique doesnt wash abrasives into the center section, I think some course sandpaper and rinsing will be most expedient. Unfortunately the corrosion is significant in the area where the ring gear is loaded but if it were mine I`d clean it up as best I could, install it and see what happens.

Tom

[BrianM]

10 minutes ago, 1965rivgs said:

 if it were mine I`d clean it up as best I could, install it and see what happens.

Tom

I agree with Tom, I would clean it up as best as I could with minimal effort and run it. I have seen much worse run out fine after a few miles and an oil change.

[60FlatTop]

The surface of the gears would have been hardened when manufactured. That depth does not go far into the metal. The rust would have taken most of that hardened layer away. In a hobby car application where one to two thousand miles per year would be average driving it might not make much difference. In a daily driving or commuter application they would wear prematurely.

 

A howl could be an issue. I would toss them and put in a new set. At my age I would just call it a reverse inheritance.

[avgwarhawk]

The rust could be troublesome.  As Bernie pointed out, the surface is hardened.  Once this surface is compromised(pitting) it can cause noise as the two surfaces mesh.  As others said, clean it up as best possible.  Install and run it.    

Edited November 11, 2022 by avgwarhawk (see edit history)

[Bloo]

If it were me, I would dunk that bad spot in evaporust for a while, maybe a week or longer. I would want that heavy rust gone, clear to the bottom of the pits and that would take a while. This time of year (in the US) I would probably add heat, as evaporust slows down horribly when cool, and stops completely at 60F if I remember correctly. It would need babysitting, moving it a little as you walk by it because evaporust causes rust right at the transition to air line, and you would have to move it slightly real often to prevent more damage. Acid based cures will skin over and won't get all the rust. Molasses might get it all but I don't know much about that.

 

Once clean, the pits will just hold oil, so no big deal there. You would just have to try it and see if it is noisy. There's nothing you can do about the missing metal, or the hardness. I think it will be fine, but you never know until you try.

 

[gungeey]

I'm definately going minimal as i don't have the experience or machinery to dismantle and reassemble it (Well,i can certainly take it apart 😅). Also don't have a lot of faith in most that say they can. The works turn very smooth. The teeth have a bearing finish.

I used oil soaked fine emery cloth followed up with crocus cloth on the rough areas only. Spent a good hour. Pic below is the worst area and as good as its getting. 

It's going in this weekend. I think it'll be fine. 

The guys at HAMB say the corrosion will hold more great oil 😄 🤣 

 

 

 

 

[avgwarhawk]

Some light pitting.  Much depends on the contact of both gears. Mostly in the  middle. The pits are near the outside edge.  Personally, I'd install it and drive it. I think it will be fine. Keep us posted.

[gungeey]

7 hours ago, RivNut said:

Molasses and water mixed 1:9.  If you can immerse the part. You probably need to know if any pitting has occurred. What's the gear ratio?

 3.07 limited slip

[gungeey]

19 minutes ago, avgwarhawk said:

Some light pitting.  Much depends on the contact of both gears. Mostly in the  middle. The pits are near the outside edge.  Personally, I'd install it and drive it. I think it will be fine. Keep us posted.

 

That's the plan, Man... What's the worst that could happen

[60FlatTop]

I just did a quick check online, $100 to $150 for either Richmond or Strange ring and pinion.

 

One of my first lessons in "don't have a professional do it" was on a gear set job. I was about 23 years old, fresh out of the Navy and blew the rearend in my 283 powered '58 Chevy wagon. It had a front loader and back then we counted ten and 12 bolt rearends by the number of bolts holding the ring gear on, not the number of cover bolts. I had picked up a set of 4.11's for it but the books showed dial indicators, torque settings, Bluing and things I was unsure of myself with. And the 4.11's had a spacer ring with longer bolts. So, with youthful caution, I dropped all the parts off with a local mechanic about the age of my father. I had heard that any previous generation had much better people at anything.

 

Luckily I have almost always had two licensed cars. About four weeks went by with no results although I saw his car parked within a few steps of the mahogany rail he rested his elbow on. I finally stopped and told him I wanted it back. He accused me of being antsy and begrudgingly left his true love to retrieve it.

 

I found it on an oil drum assembled without the spacer ring and very loose with no adjustment. He said it didn't need the ring. I calmly asked for all the parts and how much I owed him. I don't recall ever sitting with him at that mahogany rail again. I put the third member in my great grandfathers old vice, took it back apart except for the pinion, and reassembled it with the spacer.

Not having the proper tools to measure I did it by feel. "A little tight" "Opps, too much", " Ah, this feels good", and back in the car. Everything was fine. I eventually sold the car to a member of a wild, notorious family up south of me. Last time I saw it they had blown two engines and it was sitting as a rolling chassis, rearend still in tact.

 

I am sure you can equal my success. The heat treating on those gears is porked. If you never change any of the rear suspension bushes or work on the driveshaft you might not notice it. For less than 200 bucks you only do it once. I am not into the "see how it works" stuff. You have a great opportunity to only do it once. It's right under your nose now.

[gungeey]

1 minute ago, 60FlatTop said:

I just did a quick check online, $100 to $150 for either Richmond or Strange ring and pinion.

 

One of my first lessons in "don't have a professional do it" was on a gear set job. I was about 23 years old, fresh out of the Navy and blew the rearend in my 283 powered '58 Chevy wagon. It had a front loader and back then we counted ten and 12 bolt rearends by the number of bolts holding the ring gear on, not the number of cover bolts. I had picked up a set of 4.11's for it but the books showed dial indicators, torque settings, Bluing and things I was unsure of myself with. And the 4.11's had a spacer ring with longer bolts. So, with youthful caution, I dropped all the parts off with a local mechanic about the age of my father. I had heard that any previous generation had much better people at anything.

 

Luckily I have almost always had two licensed cars. About four weeks went by with no results although I saw his car parked within a few steps of the mahogany rail he rested his elbow on. I finally stopped and told him I wanted it back. He accused me of being antsy and begrudgingly left his true love to retrieve it.

 

I found it on an oil drum assembled without the spacer ring and very loose with no adjustment. He said it didn't need the ring. I calmly asked for all the parts and how much I owed him. I don't recall ever sitting with him at that mahogany rail again. I put the third member in my great grandfathers old vice, took it back apart except for the pinion, and reassembled it with the spacer.

Not having the proper tools to measure I did it by feel. "A little tight" "Opps, too much", " Ah, this feels good", and back in the car. Everything was fine. I eventually sold the car to a member of a wild, notorious family up south of me. Last time I saw it they had blown two engines and it was sitting as a rolling chassis, rearend still in tact.

 

I am sure you can equal my success. The heat treating on those gears is porked. If you never change any of the rear suspension bushes or work on the driveshaft you might not notice it. For less than 200 bucks you only do it once. I am not into the "see how it works" stuff. You have a great opportunity to only do it once. It's right under your nose now.

I hear you loud and clear Bernie.. If I don't like it the old one can go back in. I don't think these positractions quite snap together like legos. If it's crap I can yank it, and then get the owners manual and a BFH out and really ruin it LOL. It's just a fun hobby, maybe I'll get a good story to tell out of it? Steve

 

G

[avgwarhawk]

35 minutes ago, gungeey said:

 

That's the plan, Man... What's the worst that could happen

Judging by the condition after cleaning probably not much. But you know, it behind you and turning up the radio hides many noises. Drive on!  

[1965rivgs]

49 minutes ago, 60FlatTop said:

I just did a quick check online, $100 to $150 for either Richmond or Strange

Can you post a link to the replacement gear sets?? To my knowledge ring and pinion sets for the 9 3/8ths Buick only rear-end are not available?

Sounds like your choice of a professional was a professional drunk!

Tom Mooney

[telriv]

No new replacement gears for the Buick 9 3/8ths. rears ONLY used.

 

Tom T.

[gungeey]

Gotta go shopping for an o-ring 😬