Summershandy

Hydramatic side cover bolts

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Not sure if this is the best place to post. I suspected a leak from the control or throttle shaft in my hydramatic trans. The manual shows a seal inside. I took the side cover off (it will be fun putting it back, very tight against the underside of the floor) and dropped the bolts. When I was cleaning up the bolts, I noticed 5 of the 7 had brass washers. Somewhat like the ones that were on the valve cover gaskets. The other bolts had star washers. Is there a sealing factor or something I don't know or did one of the owners just run out of either or? I can't see why they can't all be stars. There's a gasket behind there. I've got time for replies as it turns out I didn't receive the proper seal on my last shipment. Hope they can find one or another post will be coming up!  I'll paint the cover and move on to another project for now. Thanks.

 

 

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I would go with all brass washers. I think they help with the sealing function whereas star washers serve some other purpose? Maybe electrical?

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Star washers are a type of lock washer. The brass ones may have been old school. Even I'm too young to know this stuff! Thanks Grizz. 

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32 minutes ago, Summershandy said:

Star washers are a type of lock washer. The brass ones may have been old school. Even I'm too young to know this stuff! Thanks Grizz. 

I take pride knowing my car is older than my dad!!

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The parts manual is not clear on which washer was used originally but it is clear that all 12 were the same and I would be inclined to think the star washer is the original.  The copper washers appear original for the side cover on the engine.  Probably could not hurt to use copper on the trans cover, even with a gasket, that was often done where extra sealing protection was needed and they should be easy to find at your local parts store (can't reuse the originals for sealing) Todd C

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Thanks Todd interesting. Never thought I would ever have to pay close attention to various washers in one application. The bottom of the side cover has 5 bolts and if I had to guess, those would be where the 5 copper washer bolts would go. I believe the bottom pan has all star washers and the gasket is a thicker material where as the side cover gasket is thin paper. I'm going to hunt around for new coppers. Like spring lock washers, I refuse to reuse them!

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1 hour ago, Summershandy said:

Thanks Todd interesting. Never thought I would ever have to pay close attention to various washers in one application. The bottom of the side cover has 5 bolts and if I had to guess, those would be where the 5 copper washer bolts would go. I believe the bottom pan has all star washers and the gasket is a thicker material where as the side cover gasket is thin paper. I'm going to hunt around for new coppers. Like spring lock washers, I refuse to reuse them!

 

If the bottom pan has the star washers that probably confirms my guess that the star washers were original on the side too.  But as we said using copper can't hurt, they were used at various times in other parts of the drivetrain.  Sounds like the leak from the side appeared with a previous owner and they did the copper washers as a repair attempt.   

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Ive got two extra hydramatics that come with the car, I’ll go down in the basement and see what they have?

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8 hours ago, Grizz said:

I’ll go down in the basement and see what they have?

 

Sure if you could, I'd be interested. My seal won't be in for a week yet so I can't put the cover back on for a time. Thanks.

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This is weird. I took pictures of what I have on both transmissions. They are in order the way they were taken out. One on the left and right and five top and bottom. They are not the same on either trans. Maybe they have been serviced before and put back in differently? Here’s the thing. We both have 7 stars and 5 coppers. This can’t be a coincidence and I’m like you in that I want it to be put back together the way it was intended. I’m glad your working on the same car as me! More digging is needed! I think copper is better for sealing so maybe those five go on the bottom?? By the way. What is under this cover? A valve body?D1DB7C95-1187-455F-9F57-8337F91F9150.thumb.jpeg.d26e1c223c3cfd6cf54517a7731de423.jpeg1D955DF6-1FA3-4A15-B79D-0AE0DA02D178.thumb.jpeg.bcd58aebb5c8ae22ba1799e73195918f.jpeg

Edited by Grizz (see edit history)

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That's crazy! No rhyme or reason there to me. I'm not overly familiar with hydra's and their innards. However, I think it would be interesting to rebuild one but I'm not pulling mine out, at least not this year. Thanks for the pic....now I'm even more baffled! LOL. We may never get the real answer except, maybe if a leak develops at a bolt with a star, replace it with a copper?

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Nah! Someone’s got an answer. Maybe we should move this question to the general forum? If that doesn’t work, car show season is upon us some old feller knows we just gotta find them.

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23 minutes ago, Grizz said:

Nah! Someone’s got an answer.

Just for fun I sent a message to Fatsco, supplier of transmission parts including hydra's. Maybe I'll hear back, maybe I won't. If I do I'll let ya know!

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My favorite hydramatic parts source is www.autotran.us , you might send the proprietor David Edwards an Email on that and definitely keep him on file for future parts if CPR does not have what you need, Todd C 

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i have the answer, and i got it from a hydra-matic rebuilding expert. the bottom five threaded holes in the main case that the side cover seals up to, are below the level of trans fluid when the transmission is filled. so the bottom five bolts need a sealing washer, not a star or lock washer. also it would help if those five bottom bolt threads get coated with anaerobic sealant too. the same anaerobic sealant should be on all the gaskets even the torus cover (flywheel) gasket and 30 bolt threads. 

 

charles l. coker

1953 pontiac tech advisor

tech advisor coordinator

pontiac oakland club int'l.

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By the sounds of it, Charles has it most correct. If I had to guess, I would have re-installed those coppers at the bottom as suggested or just replaced them all. Making sure surface areas are flat, clean and bolt holes not dimpled like valve covers.  Thanks Charles and Todd. One last interesting fact, 

People who didn't know or understand the reason for the copper washers just put the back on anywhere so it's easy to understand why some would not be in the right places today. 
 
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On 4/9/2018 at 9:07 PM, Grizz said:

I think copper is better for sealing so maybe those five go on the bottom??

C’mon guys! Nobody gonna give the young feller an “atta boy”?! Thanks for all the help!

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Really?! That’s interesting...you couldn’t find them that small or what? Is there a gasket there too? 

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Ya they were too small. I was going to auto parts and industrial shops. Must be more transmission related. There's a gasket for the cover. I'm also replacing the shaft seal and it came with a small o-ring and pin. I suspect where it goes but the way I see it, the tranny would have to be disassembled. I don't think I can replace it. Hope the leak was mostly from the seal or I'll have to live with it. I'll try to take a pic later today. 

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Better yet, here is a picture from the manual. It makes no mention of checking an o-ring for external leaks so hopefully this is not the case. The middle picture is the shaft seal I'm replacing. It's behind the side cover and it's where the throttle rods connect. There's a pin holding the smaller shaft which tells me the smaller shaft would be removed by pushing it in or moving it to the right. This is impossible because of the assembly and IMO would have to be dismantled. This smaller shaft turns within the outer shaft so there must be a seal of some sort in there. I'm not overly concerned and that's why I haven't posted anything about it. If it leaks this summer it leaks. 

 

 

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