Fixing a Tranny Leak W/Pics

[91Caprice9c1]

Hey guys, had to crack open a 5-speed from one of my metros to fix a leak originating between the two case halves. It's been pretty fun so far, have a look.







So, if anyone needs advice on how to split one of these open let me know.

-MechanicMatt

[Irk]

I like the pictures, I thought there would be more to the transmission than that, it looks pretty easy to work on. What do the syncros look like, are they in this picture? My first gear synco is going out and I'd like to replace it sometime

[hot_sd]

Nice pictures. When I saw them I realized that many people may not have seen the inside of an automatic or a rebuild of one in progress. Here are some pictures I took while rebuilding the automatic on my metro.



Inside the transmission with all of the planetary system removed (apart from the first/reverse brake piston and flange.



Second brake piston overhaul



Valve body overhaul



Forward clutch overhaul



Reassembly in progress.

[91Caprice9c1]

Originally Posted by Irk

I like the pictures, I thought there would be more to the transmission than that, it looks pretty easy to work on. What do the syncros look like, are they in this picture? My first gear synco is going out and I'd like to replace it sometime

Thanks. Yeah pretty simple really, the only part of the puzzle you aren't seeing in these pics are the 5th gear pair, which mount outside the case, behind the black cover. The synchros are the gold colored pieces which match the speeds of the dogteeth with that of the shift collar. Access to a hydraulic press and a good solid gear puller are nessecary to play with that stuff. I didn't have to disassemble the shafts this time around though - I'll have some synchro jobs comin around as some of my metros aren't shifting down to second/first - common problem. I'll be sure to document those.

HOT SD- Lovin' the photography brotha. Automatics indimidate me man - haven't bitten the bullet yet and tried my hand at one. How hard is it to play with one of these puppies?

-MechanicMatt

[hot_sd]

HOT SD- Lovin' the photography brotha. Automatics indimidate me man - haven't bitten the bullet yet and tried my hand at one. How hard is it to play with one of these puppies?

Sorry for the thread hijack – LOL. Automatics are not really that difficult to rebuild. What is more difficult is to get a good understanding of how it all works and then do a good diagnosis based on the symptoms. A rebuild manual is essential as well as learning how automatics work. For the metro you can get the ATSG manual but if you have a late model you will also need the GM FSM as this has the info on the newer TCM and OBD2 codes for the transmission.

You will also need special tools. Most automatics have custom tools for each type – this includes the metro. The GM rebuild manual (which is a different book covering all GM auto and manual transmissions) has details on these. I have a full set (got off ebay) but they are prohibively expensive if you buy them new. You can also fabricate them yourself if you are into metalworking. I had to make a special took for depressing the first/reverse brake piston in order to remove the snap ring using my metal bandsaw, welder and drill press.

Unfortunately there are very few good books on automatics and how they work. I have a couple of books on the subject including a nice one from ATRA on how all the hydraulics work. It covers pressure regulation, how boost pressure works etc and even shows using basic physics principles how to moodify the valve body components to achieve different types of shifts and so on.

Automatics are fun to work on once you understand how it all works. Have fun with them!

[91Caprice9c1]

No worries man, you didn't hi-jack, you contributed =) Thanks for the insight.

-MechanicMatt

[way]

Hey Matt,

Is there any trick to splitting the case and also taking off the black cover?

I am about to start and the black cover is on pretty good. I don't want to distort it too much if I can help it. Thanks!

[DOCTORBILL]

Holy moley, Batman !

What beautiful photos !

Please do not misunderstand me, but it would be so nice if MechanicMatt would
let someone with PhotoShop annotate those pics....or, of course, do that himself,
if he is so inclined....i.e. Label the parts in the pics.

I will need to "rebuild" my '93's 5 speed this next summer and I sure could use
some pictures with little lines pointing to specific parts such as the bearings
that can be replaced and the Syncros, and so forth and so on....

Frankly, taking apart even a manual scares the living crap out of me !

I'll be 66 next February, so by summer I will be older than Dirt and these
things look like taking apart a clock....what a puzzlement.

I notice Hot_SD put plastic sheeting down to work on his Automatic.
Lord - the number of parts ! The plastic is a nice touch for keeping things clean.

And yes! I'll bet very, very few people have seen the guts of a Manual Transmission.

Diagrams are nice, but pictures like these are worth more than diagrams can show.

How hard is it taking the Manual Transmission out ?

Johnny Mullet said it wasn't hard - putting it back was. Any comments?

Thanks for taking such nice, clear, properly exposed, well composed, in focus photos
and sharing them with us !

Outstanding !

Please keep adding as much info and pictures as possible to this thread....!

These pictures will go down in History...will help so many untold poor souls repair
those ever diminishing Geo Metros.

DoctorBill

PS - Where are the Bearings one can replace with the Rebuild Kit ?

Are you replacing the Clutch also ? More pictures...?

[redneckgeek53]

Nice pictures, Matt!

I wish I had seen those before I tore into mine! Woulda made it a whole lot easier to jump into.

Question: Did you get your leak fixed? What sort of sealant did you use? So far I have tried regular silicone gasket sealant and an anarobic gasket maker compound, and it still leaks from the seam between the two halves.

If I have to tear it apart a third time I want to fix it right!!

Thanks

[way]

Hey Doc,

I'm rebuilding a 5 speed and will post pics as I can. I'm not a pro photographer though. I'll do the best I can though.

I got the black cover off. I used a sharp putty knife and a hammer, very gently though. I used the putty knife to go through the gasket in about 5 places and gently pried it apart. Something not immediately clear from the manual is that the cover has a small tube that inserts into the main shaft:



That tube is probably best kept straight so when separating the cover, gently pry in 4 or 5 places depending on how tight it is. Mine loosened up on the first penetration but I didn't want to force things. It appears for once my mistakes in the past helped me this time.

I've almost gotten to the point where I'm going to take the countershaft nut off. The manual says to take the caulking off first but I can't see any caulking anywhere:



The yellow paint appears to be from the factory? I'm not sure on it though.

Does anyone know where the caulking should be? What does it do? Can I live without it or do I have to find something to replace it with? Does anyone have a picture of the nut with caulking in place?

[Woodie83]

Don't know anything about caulking, that's a strange choice of words. I think they're referring to the spot on the nut where it's bent down into a flat on the shaft. It's at about 5 o'clock on the picture you posted, right under the yellow paint.

[way]

I had posted this in teamswift too and you're right. I've always heard this called staking. Someone told me that caulking is also used for rivets, where I guess the metal is folded into itself or something like that. I don't know, just never heard that term before. I don't know how it goes for everyone else but I had a helluva time unstaking that nut. I basically ended up removing it with a cold chisel. I'll post up some pics a little later. There are some parts that the manual doesn't quite catch and is misleading a little too. For instance I did not need a gear puller at all which is good since there was no space for the tangs anyway. But it led to some discombobulation for me at least.

[way]

A little update.

I could not drive out that tang for the life of me. I don't have a whole wide range of punches and chisels but I can usually find a way. In this case I ended up using a small cold chisel to remove the tang:



I used to have a 1/16 " pin punch but broke it a while back.

[way]

Here's how I got the countershaft nut off. Shifting into 4th or 3rd did not help, made no difference in the resistance of the shafts so I had to figure a way to stop the shafts from turning. Once I got the shift fork removed, (it pulled off easy once I removed the circlip) Input shaft 5th gear and countershaft 5th gear both pulled off easily by hand, no puller required. With so little clearance I don't know how I'd have gotten a puller in there anyway. So what I did was just wrap some nylon strapping around the input shaft, enough to be about a half inch thick and then used some slip joint pliers to grip it with. I could hold as tight as I wanted without risking damage to the teeth:



I could not find any place that had a 26 mm socket so I went to my regular SAE sockets. I found that a 1 1/16" socket was pretty close so I used it with the electric impact gun. Seemed to work ok:



Of course with the tang knocked out, I'm going to replace the nut anyway. But even so, the nut would still be usable if the tang were still there.