rebuiling auto trans.degree of difficulty.
12-20-2010, 05:56 PM
#61
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12-20-2010, 06:19 PM
#62
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12-21-2010, 04:20 AM
#63
Chronic Tool Dropper
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Of course, K says she "misses me" when I'm away. Maybe with more time at closer range, her aim will be "good enough" one of these days. THEN it will be OK for you to think about getting out of the biz.
12-21-2010, 05:31 AM
#64
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Tom,
I have a couple of core three speed trans. One is partly disassembled. I have a rebuilt 4 speed if you have faith in my ability. I have two other 84-86 auto trans in working cars. I also have an 87 four speed with 23K on it, but it has been sitting for a while.
I have a couple of core three speed trans. One is partly disassembled. I have a rebuilt 4 speed if you have faith in my ability. I have two other 84-86 auto trans in working cars. I also have an 87 four speed with 23K on it, but it has been sitting for a while.
12-21-2010, 09:35 AM
#65
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I'm heading down the path of rebuilding my old 4-speed auto.
I was quoted $3750 and $4200 for professional rebuilding. With the value of our cars as low as they are, it's almost un-justifiable for the early 16v cars.
I know used units are available, but you still should have some things done. TC bearings and bolts, front pump seals etc. If I can learn to rebuild it, I can keep my car running if parts are available.
I've rebuilt 2 of the 4-speed valve bodies. The first was from the old trans just to see if I could do it and practice. The second was pulled from a running trans due to hard shifting. When I opened it up, it was black inside. Dirt and grit accumulated in the passages and bores so bad the valves were hard to move in teh bores. After cleaning, replacing springs and a couple screens it shifts much smoother. It really wasn't that difficult and parts were available. The WSM, Jim M's CD set and information I collected on the 722 trans (from a MB website), made it doable. No special tools (maybe a magnet for the *****), big and small screwdriver, metal pans, lint free wipes and clean ATF.
I have all the parts to the old trans but the sun gear and one of the clutch housings are damaged so I need those parts. Both parts new are $$$, so I'm looking for some good used parts.
I'm interested in any 4 or 3 speed (I have both) A/T rebuilding anyone has done and has information to share. I though about documenting the valve body rebuilding, but didn't think many would be interested.
I was quoted $3750 and $4200 for professional rebuilding. With the value of our cars as low as they are, it's almost un-justifiable for the early 16v cars.
I know used units are available, but you still should have some things done. TC bearings and bolts, front pump seals etc. If I can learn to rebuild it, I can keep my car running if parts are available.
I've rebuilt 2 of the 4-speed valve bodies. The first was from the old trans just to see if I could do it and practice. The second was pulled from a running trans due to hard shifting. When I opened it up, it was black inside. Dirt and grit accumulated in the passages and bores so bad the valves were hard to move in teh bores. After cleaning, replacing springs and a couple screens it shifts much smoother. It really wasn't that difficult and parts were available. The WSM, Jim M's CD set and information I collected on the 722 trans (from a MB website), made it doable. No special tools (maybe a magnet for the *****), big and small screwdriver, metal pans, lint free wipes and clean ATF.
I have all the parts to the old trans but the sun gear and one of the clutch housings are damaged so I need those parts. Both parts new are $$$, so I'm looking for some good used parts.
I'm interested in any 4 or 3 speed (I have both) A/T rebuilding anyone has done and has information to share. I though about documenting the valve body rebuilding, but didn't think many would be interested.
2. For those whose knees aren't wobbly, its time for us to fully-document, with Dwayne-style writeups, the rebuilds of the autos and manuals. I've got a lot of pictures of the B2 piston swap I did on an 85, plus the disassembly of the 84. More to come in 2011.
12-22-2010, 12:19 AM
#66
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Dan,
What MY is the 4-speed you rebuilt and is it with diff or without?
If your not far from Santa Clara, I will be there in early February for DesignCon.
If you have some time and could meet me (they don't let me have a car), maybe we could work something out so I could take a look?
Cheers,
What MY is the 4-speed you rebuilt and is it with diff or without?
If your not far from Santa Clara, I will be there in early February for DesignCon.
If you have some time and could meet me (they don't let me have a car), maybe we could work something out so I could take a look?
Cheers,
Last edited by Tom928; 12-22-2010 at 01:30 AM.
12-22-2010, 01:21 AM
#67
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Here are pictures of the gears. One is the planetary gear carrier and the other is the drive shaft. The planetary gear carrier has a ring of chips one one gear all the way around on the edge. The drive shaft has a bad chip out of it as shown in the second pic.
The K1 clutch(?) housing has the gear with a large concave washer that has 24 springs under it (every 6th spring is missing out of the 24 so only 20 are installed.). As you can see the concave washer looks badly galled. The shop wanted to replace the entire housing but it looks like the washer is replaceable?
I agree we should be documenting what we do. I have very few pics of the valve body rebuild. I just might take the valve body I practiced on apart again and do a white paper procedure on it with pics and such.
Cheers,
The K1 clutch(?) housing has the gear with a large concave washer that has 24 springs under it (every 6th spring is missing out of the 24 so only 20 are installed.). As you can see the concave washer looks badly galled. The shop wanted to replace the entire housing but it looks like the washer is replaceable?
I agree we should be documenting what we do. I have very few pics of the valve body rebuild. I just might take the valve body I practiced on apart again and do a white paper procedure on it with pics and such.
Cheers,
12-22-2010, 05:24 AM
#68
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I made a number of special tools for the rebuild. If I get a chance I will take some pictures and post them to my web site. They were cheap and easy to make. One was for disassembling the springs.
12-22-2010, 11:05 AM
#69
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Greg, Greg... now you're talking about quality, and that's a hard thing to nail down, it's value is different for every observer/implementer. The fundamental tests are does it work?, and for how long?
Talent is not a replacement for persistence and determination nor is it always a requirement for success.
Talent is not a replacement for persistence and determination nor is it always a requirement for success.
12-23-2010, 10:47 PM
#70
Under the Lift
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Sure, I'll bet you can save a whole lot of money in labor charges rebuilding your own AT. Reminds me of my first engine rebuild when I was in high school. The local shop wanted $500 to rebuild it (this was 1964). That was a whole lot of money to me. So, I bought an official shop manual for the car and started in on the project, never having done anything similar before. Heck, I had the whole summer. About a month and a half of 8 to 12 hour days later I had broken well over $500 in parts, had redone the rebuild a few times, but eventually I finished and the car ran perfectly. So, if you have at least a few months of free time to burn and a few grand for parts, go for it!
12-24-2010, 06:59 PM
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Bill,
But think of what you learned. I did have to tear down the clutch packs about three times to get the shim difference right. But once I learned the sequence it was a piece of cake.
In an auto rebuild you are mostly replacing seals. You can replace the clutchs too if they are worn. Mine were well with in specs but I had already ordered the clutchs, so I used the new ones. The shim offsets turned out to be identical, which has been my experience for most manual trans work. I always make sure not to mix up the shims.
But on the auto it is easy to measure the depths and double check things. That was the biggest learning curve was in the measurement and how to get certain things apart. I do not know all the technical names so forgive me - I am not good with names. There were some things that disassemble and only get new seals - there are a lot of seals in an automatic. But the kits are cheap.
I had to make a couple of tools for the disassemble and reassembly but they were easy to make from PVC.
If the weather every stops raiining and gets warm I will be glad to host a rebuild session. Just bring the kit and a clean transmission along with what was wrong with it. Some one will have to be my fingers as mine no longer work as they should - but then it is a learning process. I did not rebuild the valve body but I did not think this necessary. I hear that is another job - espeically if you mix the pistons up.
But think of what you learned. I did have to tear down the clutch packs about three times to get the shim difference right. But once I learned the sequence it was a piece of cake.
In an auto rebuild you are mostly replacing seals. You can replace the clutchs too if they are worn. Mine were well with in specs but I had already ordered the clutchs, so I used the new ones. The shim offsets turned out to be identical, which has been my experience for most manual trans work. I always make sure not to mix up the shims.
But on the auto it is easy to measure the depths and double check things. That was the biggest learning curve was in the measurement and how to get certain things apart. I do not know all the technical names so forgive me - I am not good with names. There were some things that disassemble and only get new seals - there are a lot of seals in an automatic. But the kits are cheap.
I had to make a couple of tools for the disassemble and reassembly but they were easy to make from PVC.
If the weather every stops raiining and gets warm I will be glad to host a rebuild session. Just bring the kit and a clean transmission along with what was wrong with it. Some one will have to be my fingers as mine no longer work as they should - but then it is a learning process. I did not rebuild the valve body but I did not think this necessary. I hear that is another job - espeically if you mix the pistons up.
