727 Rebuild help
- Thread starter NewcScout
- Start date
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
I lubricate all parts with transemble (or any other sort of transmission assembly goop). It's used on all seal lips, bearings, between shims/spacers that rotate, bushing friction areas, etc.
I use actual atf only to soak the frictions before assembly.
Plenty of lube during assembly is imperative both for initial rotation and to keep the parts in their proper positions during assembly.
I use actual atf only to soak the frictions before assembly.
Plenty of lube during assembly is imperative both for initial rotation and to keep the parts in their proper positions during assembly.
NewcScout
Member
A bit more here now....
I drilled out the rear clutch piston retainer. I used the drill press for the straight holes and a hand drill for the 70-75 degree holes.
The instructions call to replace the input shaft seals with the hook-type seal rings. The only rings that fit in the kit were some composite/plastic rings that are not hook type. They do seem to be the correct size. Any ideas? The old one is on the right and the new one is on the left.
Next I put together the rear clutch assembly.
Now I'm onto the front clutch. I have a couple of questions here.
1. There is a ring groove in the bottom inside the clutch retainer. Should there be a ring there? I have 2 rings(1 straight and one wavy one) when I pulled it apart the wavy one was on the outside. I don't remember where the straight one came from
2. There were 4 friction plates and 4 steel plates in the front clutch when I disassembled it. There are 5 of each in the kit. If I put 4 in the kit there is a large distance between the thick flat pressure plate and the wavy ring. Way outside the 0.060-0.080 spec. If I install all 5 friction plates and steel plates, then with a little pressure I can fit a 0.060 feeler gauge in between the low spots of the wavy ring and the top of the thick flat pressure plate.
Now onto the rear servo.
The instructions call to add a shimto the servo shaft. There are 2 possible shims that fit on the shaft. I put them both on the shaft and they are in the picture below. One is steel and the other one appears to be teflon. The steel one will keep all the play out of the spring. The shaft would not be able to move at all.
Help!!
Thanks!
I drilled out the rear clutch piston retainer. I used the drill press for the straight holes and a hand drill for the 70-75 degree holes.
The instructions call to replace the input shaft seals with the hook-type seal rings. The only rings that fit in the kit were some composite/plastic rings that are not hook type. They do seem to be the correct size. Any ideas? The old one is on the right and the new one is on the left.
Next I put together the rear clutch assembly.
Now I'm onto the front clutch. I have a couple of questions here.
1. There is a ring groove in the bottom inside the clutch retainer. Should there be a ring there? I have 2 rings(1 straight and one wavy one) when I pulled it apart the wavy one was on the outside. I don't remember where the straight one came from
2. There were 4 friction plates and 4 steel plates in the front clutch when I disassembled it. There are 5 of each in the kit. If I put 4 in the kit there is a large distance between the thick flat pressure plate and the wavy ring. Way outside the 0.060-0.080 spec. If I install all 5 friction plates and steel plates, then with a little pressure I can fit a 0.060 feeler gauge in between the low spots of the wavy ring and the top of the thick flat pressure plate.
Now onto the rear servo.
The instructions call to add a shimto the servo shaft. There are 2 possible shims that fit on the shaft. I put them both on the shaft and they are in the picture below. One is steel and the other one appears to be teflon. The steel one will keep all the play out of the spring. The shaft would not be able to move at all.
Help!!
Thanks!
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
The soft parts kit is not produced by B&M but is sourced from an outside vendor. The contents of those kits change over time. The inclusion of the teflon seal rings is one of several changes made over the years. And they do not have interlocking ring ends, just flat tips. Use 'em anyway, there are no other rings in the kit.
The "white", small plastic ring is the gasket for the included drain plug kit to be installed in the pan as an option. The steel spacer is the correct one to use on the piston.
For the front clutch, the "wavy" retaining ring is used. However, on some older units, a flat ring was used that was a selective fit item.
I believe the "flat" ring you have is the one used on the rear clutch as the retaining ring.
With the set of five frictions in the clutch, as long as you can meet the specification limits for free play, you are ok. A distance of 0.060 is barely outside the dimension but will work just fine.
You will also see that the clutch frictions used are the same compound/configuration for both front and rear clutches. That was not the case regarding the oem clutch frictions which are a different compound front and rear. Again...this is an improvement for the B&M parts setup as compared to oem stuff.
I'm going into the hospital tomorrow (July 26) for some coronary repairs, won't be home until Wednesday nite. I'll have my cell with me but no computer, I'll be able to post a short response if needed until I get home Wednesday nite.
The "white", small plastic ring is the gasket for the included drain plug kit to be installed in the pan as an option. The steel spacer is the correct one to use on the piston.
For the front clutch, the "wavy" retaining ring is used. However, on some older units, a flat ring was used that was a selective fit item.
I believe the "flat" ring you have is the one used on the rear clutch as the retaining ring.
With the set of five frictions in the clutch, as long as you can meet the specification limits for free play, you are ok. A distance of 0.060 is barely outside the dimension but will work just fine.
You will also see that the clutch frictions used are the same compound/configuration for both front and rear clutches. That was not the case regarding the oem clutch frictions which are a different compound front and rear. Again...this is an improvement for the B&M parts setup as compared to oem stuff.
I'm going into the hospital tomorrow (July 26) for some coronary repairs, won't be home until Wednesday nite. I'll have my cell with me but no computer, I'll be able to post a short response if needed until I get home Wednesday nite.
NewcScout
Member
Ok. I took a few days off, but I'm back again.
It turns out the ring that I had was from the front clutch. It went below the piston. But still with all the plates in, I still got 5 pressure plates in within tolerance.
So, moving on.....
Put together the rear servo piston with metal spacer. This will remove almost all travel from the spring. There is perhaps .050 play on the servo shaft after the spacer is in.
The accumulator blocker rod does just that. Doesn't allow the accumulator piston to move at all. It sits now in its all-the-way-up position. This is a B&M add in.
Next I installed the front servo. This was by far the dirtiest place in the tranny. It took a bit to clean it. The instructions said to replace all 3 seal rings, but only provided 2 of them. My seal rings were in very good shape, so I cleaned one off real well and reused it. I also used a big c-clamp to compress the larger servo spring. The directions called to compress it until you could put a screwdriver into the pipe plug hole before installing the retainer clip, but that seemed like you'd need to compress that spring really far. The c-clamp worked well to get it in far enough to get the ring in.
Now I installed the output shaft support. The instructions called to put the shaft support in the freezer for an hour to get it to fit. Mine slipped in ok. Tight with no play, but ok. I didn't have to force it. Torqued the bolts to 150in-lbs. Silly they wouldn't just say 12.5ft-lbs since every torque wrench I have is labeled in nm or ft-lbs.
That's all for now. Perhaps more tomorrow....
It turns out the ring that I had was from the front clutch. It went below the piston. But still with all the plates in, I still got 5 pressure plates in within tolerance.
So, moving on.....
Put together the rear servo piston with metal spacer. This will remove almost all travel from the spring. There is perhaps .050 play on the servo shaft after the spacer is in.
The accumulator blocker rod does just that. Doesn't allow the accumulator piston to move at all. It sits now in its all-the-way-up position. This is a B&M add in.
Next I installed the front servo. This was by far the dirtiest place in the tranny. It took a bit to clean it. The instructions said to replace all 3 seal rings, but only provided 2 of them. My seal rings were in very good shape, so I cleaned one off real well and reused it. I also used a big c-clamp to compress the larger servo spring. The directions called to compress it until you could put a screwdriver into the pipe plug hole before installing the retainer clip, but that seemed like you'd need to compress that spring really far. The c-clamp worked well to get it in far enough to get the ring in.
Now I installed the output shaft support. The instructions called to put the shaft support in the freezer for an hour to get it to fit. Mine slipped in ok. Tight with no play, but ok. I didn't have to force it. Torqued the bolts to 150in-lbs. Silly they wouldn't just say 12.5ft-lbs since every torque wrench I have is labeled in nm or ft-lbs.
That's all for now. Perhaps more tomorrow....
Michael Mayben
IHPA Tech Moderator - Retired & No Longer Online
All is good!
Regarding the "blocking" of the front servo piston with a rod through the port...don't see how that can actually be done safely on these units. The proper method is exactly what you did! I use a very small valve spring compressor in the same manner.
Regarding the "blocking" of the front servo piston with a rod through the port...don't see how that can actually be done safely on these units. The proper method is exactly what you did! I use a very small valve spring compressor in the same manner.
NewcScout
Member
Alright, slowly but surely, I'm getting there.
Here's what last night held:
put back in all the rollers and springs. I don't really know why the kit didn't include the springs.
Then onto the governor and the output shaft. I put he governor back together wit a touch of gun oil. This seemed to really help with this part.
After that installed the output shaft
Installed the park latch mechanism in the output shaft housing, reinstalled the output bearings, and put the rear seal in as well.
Then I put in the kickdown band. I soaked the band in atf prior to putting it in. The direction said that this would "snap" into place. Not really. I had to back off the adjustment bolt back a ways to get it to fit.
The low/reverse drum carefully goes in. Don't knock out our overrun clutch rollers and springs.
Then went in the rear annulus gear, rear planetary set, and sun gear. I kept them all together when I put them in.
Then went on the thrust washer
Followed by the input shaft and clutch assemblies. This was a bit tricky while the tranny is on its side. So I stood it up and worked it down into the sun gear.
I then installed the pump. The instructions called to put the pump in without the seals or gasket to make sure all of the clutch packs are lined up. This was a really good tip as I wasn't fully seated and this caught it. But I took the clutch packs out and reseated them and tried it again and all is well.
More to come......
Here's what last night held:
put back in all the rollers and springs. I don't really know why the kit didn't include the springs.
Then onto the governor and the output shaft. I put he governor back together wit a touch of gun oil. This seemed to really help with this part.
After that installed the output shaft
Installed the park latch mechanism in the output shaft housing, reinstalled the output bearings, and put the rear seal in as well.
Then I put in the kickdown band. I soaked the band in atf prior to putting it in. The direction said that this would "snap" into place. Not really. I had to back off the adjustment bolt back a ways to get it to fit.
The low/reverse drum carefully goes in. Don't knock out our overrun clutch rollers and springs.
Then went in the rear annulus gear, rear planetary set, and sun gear. I kept them all together when I put them in.
Then went on the thrust washer
Followed by the input shaft and clutch assemblies. This was a bit tricky while the tranny is on its side. So I stood it up and worked it down into the sun gear.
I then installed the pump. The instructions called to put the pump in without the seals or gasket to make sure all of the clutch packs are lined up. This was a really good tip as I wasn't fully seated and this caught it. But I took the clutch packs out and reseated them and tried it again and all is well.
More to come......
NewcScout
Member
Thanks jason,
I'm glad you are getting something from it.
As far as the B&M instructions go, I'd give them a b-. They give a good checklist of what you should do. But the specifics are a little weak. They don't really do a good job of referencing parts and what they should look like. They also assume that the is preexisting knowledge on automatic trannies. This is where michael and the forum come in I guess.
My other brig complaint with the kit instructions is that the pictures are almost useless. You have to take a lot of pictures when you are taking it apart to know how it goes back together. Cause the pictures in the instructions are so bad.
The other reference I used was the munroe book. It has pretty good general instructions during the rebild process. All of the kit specific stuff is only in the B&M book.
There have also been some funny things that the instructions suggest that be done that simply don't make sense from both a safety standpoint as well as practicality. But I think that anyone that is mechanically inclined and has a clue how to maneuver around a shop could figure out.
I hope this helps.
Let me know if you have any questions. I'd be happy to help.
Cheers,
drew
I'm glad you are getting something from it.
As far as the B&M instructions go, I'd give them a b-. They give a good checklist of what you should do. But the specifics are a little weak. They don't really do a good job of referencing parts and what they should look like. They also assume that the is preexisting knowledge on automatic trannies. This is where michael and the forum come in I guess.
My other brig complaint with the kit instructions is that the pictures are almost useless. You have to take a lot of pictures when you are taking it apart to know how it goes back together. Cause the pictures in the instructions are so bad.
The other reference I used was the munroe book. It has pretty good general instructions during the rebild process. All of the kit specific stuff is only in the B&M book.
There have also been some funny things that the instructions suggest that be done that simply don't make sense from both a safety standpoint as well as practicality. But I think that anyone that is mechanically inclined and has a clue how to maneuver around a shop could figure out.
I hope this helps.
Let me know if you have any questions. I'd be happy to help.
Cheers,
drew
david30101
New member
This May be a stupid question, I just reassembed my transmission minus the tc. Just makeing sure, does the outer reaction shaft on the oil pump turn at all? (outer larger one, not the smaller inside one). I not sure if that was a fixed shaft and not susposed to turn or not. When I put the torque converter on, it turns "normally".
david30101
New member
Thanks, just making sure. I just had mine apart. Should know better..lol.
NewcScout
Member
So now onto the valve body...
First pulled the filter off the valve body assembly.
Then pulled off the pressure regulator spring retainer and then pulled the regulator valve and converter valve. They fall right out.
I then unscrewed the 13(not 14 as the instructions said) screws and separated the casting and the separator plate/transfer plate. A little care here pays off. There are 7 total balls in there and one on a spring. The instructions let you know to pay attention here.
Next was the shift valve end plate and the 1-2 shift control valve, the 1-2 shift valve, and the 2-3 shift valve and all of their springs.
Then came out the governor plug end plate and then the 1-2 shift valve governor plug, 2-3 shift valve governor plug, and the shuttle valve throttle plug.
At this point the directions said to go directly into drilling. My thoughts were that before I begin drilling and getting aluminum flakes down inside the shift selector valve channels I should disassemble the shift selector lever assembly. So here's what I did.(sorry if the terminology is wrong, none of this was in the directions)
pulled the park shaft assembly
Pulled the shifter connection shaft assembly and the valves
I pulled the 6 screws to remove the plate on the opposite side of the valve body and pulled the valve and spring assembly that was under the plate. The instructions don't tell me what this is.
There were 2 screws holding a small plate on the valve body. I pulled this plate and the valve assembly inside. I don't know what this one does too. It wasn't in the directions.
Back to direction instruction.
Pulled the 4 small screws and separated the separator plate and the transfer plate.
Now onto drilling......
First pulled the filter off the valve body assembly.
Then pulled off the pressure regulator spring retainer and then pulled the regulator valve and converter valve. They fall right out.
I then unscrewed the 13(not 14 as the instructions said) screws and separated the casting and the separator plate/transfer plate. A little care here pays off. There are 7 total balls in there and one on a spring. The instructions let you know to pay attention here.
Next was the shift valve end plate and the 1-2 shift control valve, the 1-2 shift valve, and the 2-3 shift valve and all of their springs.
Then came out the governor plug end plate and then the 1-2 shift valve governor plug, 2-3 shift valve governor plug, and the shuttle valve throttle plug.
At this point the directions said to go directly into drilling. My thoughts were that before I begin drilling and getting aluminum flakes down inside the shift selector valve channels I should disassemble the shift selector lever assembly. So here's what I did.(sorry if the terminology is wrong, none of this was in the directions)
pulled the park shaft assembly
Pulled the shifter connection shaft assembly and the valves
I pulled the 6 screws to remove the plate on the opposite side of the valve body and pulled the valve and spring assembly that was under the plate. The instructions don't tell me what this is.
There were 2 screws holding a small plate on the valve body. I pulled this plate and the valve assembly inside. I don't know what this one does too. It wasn't in the directions.
Back to direction instruction.
Pulled the 4 small screws and separated the separator plate and the transfer plate.
Now onto drilling......
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NewcScout
Member
So now the drilling.
I installed the drill guide plate that came with the kit. I then used the little measurement paper that came with the kit to set the depth of the drill by adding some tape. It didn't land directly on the rib. It was offset slightly to the side. It left a great deal of material burr that I had to cut off of the rib. I did this with a small sharp file. This picture is not too good but it was the best my little camera could do.
After that I drilled out the proper places in the transfer plate outlined in the directions. This left a bit of burr behind too. I removed it with a file.
Next I disassembled the throttle kick-down assembly in the limit valve spring end plate. The kit came with a new spring. It is the larger of the 2 shown below.
The shift valves got installed next. Simply cleaned and reinstalled the old valves and springs. The directions call to add a 1/4" ball into the 1-2 shift valve.
The end plate goes on next with a little pressure as those springs are pushy.
Governor plug valves are next. The kit comes with 4 new 1-2 shift governor plugs. It shows you which one to use. These are all machined but not deburred. Their edges are pretty sharp and don't slide through the body well. I used some 220 sand paper and oil to take the edge off of the machining.
After I put the rest of the governor plugs in and placed their end plate on I put the shuttle valve back in.
Next I put in both pressure regulator converter valves.
I then put the drilled transfer plate, the separator plate, and the valve body back together.
Since I took the shift control/kickdown assembly off, I put all that back on now. The instructions didn't call for removal of all of this, but I pulled it all and cleaned it all.
Now I put back on the spring retainer and adjusted the throttle pressure and the the pressure regulator adjustment. All of this is outlined in the directions.
More on next post.......
I installed the drill guide plate that came with the kit. I then used the little measurement paper that came with the kit to set the depth of the drill by adding some tape. It didn't land directly on the rib. It was offset slightly to the side. It left a great deal of material burr that I had to cut off of the rib. I did this with a small sharp file. This picture is not too good but it was the best my little camera could do.
After that I drilled out the proper places in the transfer plate outlined in the directions. This left a bit of burr behind too. I removed it with a file.
Next I disassembled the throttle kick-down assembly in the limit valve spring end plate. The kit came with a new spring. It is the larger of the 2 shown below.
The shift valves got installed next. Simply cleaned and reinstalled the old valves and springs. The directions call to add a 1/4" ball into the 1-2 shift valve.
The end plate goes on next with a little pressure as those springs are pushy.
Governor plug valves are next. The kit comes with 4 new 1-2 shift governor plugs. It shows you which one to use. These are all machined but not deburred. Their edges are pretty sharp and don't slide through the body well. I used some 220 sand paper and oil to take the edge off of the machining.
After I put the rest of the governor plugs in and placed their end plate on I put the shuttle valve back in.
Next I put in both pressure regulator converter valves.
I then put the drilled transfer plate, the separator plate, and the valve body back together.
Since I took the shift control/kickdown assembly off, I put all that back on now. The instructions didn't call for removal of all of this, but I pulled it all and cleaned it all.
Now I put back on the spring retainer and adjusted the throttle pressure and the the pressure regulator adjustment. All of this is outlined in the directions.
More on next post.......
NewcScout
Member
Next I placed the filter on the valve body assembly.
Placed the plug into the transmission body.
And put the valve body into the transmission.
Drilled out the place for the drain plug.
Installed the drain plug and put the pan on the transmission.
Done!!!
Now I get to wait until I get the xcase in as well as put the rest of the truck together to see if this works at all.........
Thanks for all the help everyone.
Cheers,
drew
Placed the plug into the transmission body.
And put the valve body into the transmission.
Drilled out the place for the drain plug.
Installed the drain plug and put the pan on the transmission.
Done!!!
Now I get to wait until I get the xcase in as well as put the rest of the truck together to see if this works at all.........
Thanks for all the help everyone.
Cheers,
drew
Fishwagon
New member
Drew,
excellent write up. I was doing mine at the exact time as you were (just now buttoned it up) and I was following your write up as I was doing it as well.
Those images in the directions are horrible.......but the kit is pretty straightforward to put in.
May I also recommend, for anyone watching this, there is a series of youtube videos on this rebuild as well (although not with the bmw kit). The videos will not help with the B&M specifics, but they really help with teardown/inspection/reassembly of main components.
This is first video in the series:
rebuilding 727 torqueflite 600hp part1 - youtube
To anyone thinking of doing this themselves, I would not hesitate to recommend so. Get the following book also:
amazon.com: torqueflite a-727 transmission handbook hp1399: how to rebuild or modify chrysler's a-727 torqueflite for all applications (9781557883995): carl munroe: books
Now I'm with drew, get to wait to put it in and see what happens!
Rich
excellent write up. I was doing mine at the exact time as you were (just now buttoned it up) and I was following your write up as I was doing it as well.
Those images in the directions are horrible.......but the kit is pretty straightforward to put in.
May I also recommend, for anyone watching this, there is a series of youtube videos on this rebuild as well (although not with the bmw kit). The videos will not help with the B&M specifics, but they really help with teardown/inspection/reassembly of main components.
This is first video in the series:
rebuilding 727 torqueflite 600hp part1 - youtube
To anyone thinking of doing this themselves, I would not hesitate to recommend so. Get the following book also:
amazon.com: torqueflite a-727 transmission handbook hp1399: how to rebuild or modify chrysler's a-727 torqueflite for all applications (9781557883995): carl munroe: books
Now I'm with drew, get to wait to put it in and see what happens!
Rich