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-   -   I found something in my transmission!! (https://www.rx7club.com/1st-generation-specific-1979-1985-18/i-found-something-my-transmission-927932/)

rwatson5651 10-24-10 01:10 AM

I found something in my transmission!!
 
3 Attachment(s)
I am building my new engine and so as a matter of course I removed the front cover of the transmission (79 5 speed) in order to put in a fresh front seal and gasket and found this:


I found it here at the bottom of the front cover, where the screw driver is pointing:

It is not metal and appears to be some kind of plastic or hard fiber and it is "chunks" not filings.

The trans was driving perfectly when I took it down, I was just changing the front and rear seal as a matter of course, no grinding and the syncros were working well.

Anyone know what it is?????

Attachment 408076

Attachment 408077

Attachment 408078

Rotary_Junkie 10-24-10 01:16 AM

BUMP thats weird man, cant help ya there. only thing in mind is somthing got in there that wasnt suppost.

Jeff20B 10-24-10 11:48 AM

Speedo drive gear chunks?

I've had pieces of gears (metal) end up in that little area but haven't found plastic yet.

rxtasy3 10-24-10 12:15 PM

going by the color i'd say speedo gear as well. pieces of metal gear, being heavier, tend to fall to the bottom of the case. the plastic pieces would float around more and i guess could find their way there. gear teeth i've broken but never had a speedo gear do that.

j9fd3s 10-24-10 12:16 PM

some of the bearings along the line have been sealed, i wonder if that is one of the bearing seals?

mazdaverx713b 10-24-10 01:34 PM

could be either things mentioned. speedo drive gear chunks would have a hard time getting up there and settling but it is possible. i also wonder if its a solidified grease of some sort.. thats a tough one

rwatson5651 10-24-10 05:21 PM

Too solid for grease, even hardened grease would not be as solid as these pieces, the speedo gear sounds like the best guess, but the speedometer still works fine, I may pull it to see if there is any damage,

Is there anything from back around the shifter that could have crumbled and fell down into the trans?

The shifter feels good w/o any unusual looseness etc.

I guess if it aint broke I wont fix it.....so I will put it back in and keep driving it!

Jeff20B 10-24-10 08:07 PM

Good idea.

Crispin38 10-24-10 09:52 PM

If it shifts good i wouldn't worry about it. I know internally my tranny has to be in bad shape, but it shifts great so.
Just make sure you're running good fluid.

DivinDriver 10-25-10 10:31 AM

It sure does look like old nylon bits. You might try hitting it with some brake cleaner and see if the color clears up.

I'd guess speedo gear chunks, too. If you pull your speedo sender and the gear looks fine, I'd guess maybe the PO had one fail and replaced it.

Being an SA trans without the rear-remoted shifter box, it's may also have started life as the lower nylon bushing from the shifter. They're likewise nylon and one could have dropped in and gotten ground up by the trans, and been previously replaced.

rwatson5651 10-25-10 11:37 AM

However, the more I think about it the more I doubt that anything from that far back in the transmission could migrate and group together at the very front of the trans, if I remember correctly from the one time I rebuilt one of these about 15 years ago the front and rear of the actual gearbox would make it difficult for these pieces to move all the way to the front, so I am beginning to think it must be a bearing seal that crumbled, probably one of the front bearings.

Just a guess.......Im baffled

DallasFC1 10-28-10 09:36 AM

Now im curious
 
HEH,
You got me really curious.. and since I can't come look at yours, I'll tear into one of my spare transmissions in the garage and see whats in mine that ain't in yours. I'm honestly thinking there may have been a nylon/vinyl/or teflon, spacer of some sort that was heat fatigued and fell into the bearing as it was turning. making the bearing a blender :)

I'll let ya know what I find :) All else fails, you can clean a big piece of it real real good. Then burn it and watch the flame / smoke and see what has those burn characteristics.

:)

rwatson5651 10-28-10 11:05 AM

When you tear it down look at the "partitions" (for lack of a better word) in the gear box to see if it's possible for parts or pieces to move from the rear to the front, also look at the bearings on the input shaft at the very fron to see of they have any shields or seals, mine do not and that may be where the debris originated from. I have cleaned the parts better and will post another pic of them and will do the test that you described. Let me know what you discover, I, like you am curious!

GeenIdee 10-28-10 11:53 AM

a cage of one of the bearings maby?

dj55b 10-28-10 12:03 PM

does the bottom bearing have a plastic cover on it normally? I don't remember when I did mine.

rwatson5651 10-28-10 02:54 PM

I cannot remember if either of the front bearings had a seal or some kind of plastic shield or not. It's been years since I've looked at one.

DallasFC1 10-28-10 07:21 PM

Problem Solved
 
3 Attachment(s)
The bearings have a seal on them (lower smaller shaft bearing).

See the pics attached. the destruction you have is the front cover for the bearing that was chewed up and spit out :)

Since it did this I would check for play in the shafts and proceed accordingly.

Hope this helps bro!

rwatson5651 10-28-10 07:34 PM

Mystery Solved!!!!!!!

Thanks Dallas, your photo tells the story, I do appreciate the trouble you went to to remove the front cover and post the pic.

What would I do w/o this forum?

j9fd3s 10-28-10 09:09 PM

ive seen the bearings with and without those seals, mazda changed their minds about that periodically.

i believe a new factory bearing will be sealed, but the aftermarket ones won't

dj55b 10-28-10 09:47 PM

thought so :) the bearing might still be fine and the plastic just failing from over time .


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