Rear Flex Plate - Clarification needed
09-18-2007, 06:28 PM
#16
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Sean,
Do the bolt conversion and get it over with while you're here. The riveted rear flexplates have been known to vibrate loudly when the rivets loosen with time. There will be a horrible noise coming from the trans one day which will only get worse until you tear it down again.
Hopefully Jim can find the TSB.
Good luck,
Constantine
Do the bolt conversion and get it over with while you're here. The riveted rear flexplates have been known to vibrate loudly when the rivets loosen with time. There will be a horrible noise coming from the trans one day which will only get worse until you tear it down again.
Hopefully Jim can find the TSB.
Good luck,
Constantine
09-18-2007, 07:00 PM
#18
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Jim,
I thought the same as you did - I am glad I asked the question.
Roger
I thought the same as you did - I am glad I asked the question.
Roger
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
09-18-2007, 09:38 PM
#20
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You will need the following from Porsche. Use loctite on the bolts. Torque Nuts to 33Nm / 23ft.lbs. Also Change the bearings
8 Bolts N 010 240 7
8 nuts N011 008 8
8 Washers N 011 525 19
If you need more information I can make a PDF installation guide.
8 Bolts N 010 240 7
8 nuts N011 008 8
8 Washers N 011 525 19
If you need more information I can make a PDF installation guide.
09-18-2007, 09:48 PM
#21
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Steve,
What have you seen as far as rivets in the different 928 model years? Were they stopped after a certain MY?
As far as the bolt conversion, I used locking washers and loctite (yes, loctite) on the nuts/bolts. Did not want them to even think of coming loose!
Constantine
What have you seen as far as rivets in the different 928 model years? Were they stopped after a certain MY?
As far as the bolt conversion, I used locking washers and loctite (yes, loctite) on the nuts/bolts. Did not want them to even think of coming loose!
Constantine
09-18-2007, 10:55 PM
#22
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Steve,
What have you seen as far as rivets in the different 928 model years? Were they stopped after a certain MY?
As far as the bolt conversion, I used locking washers and loctite (yes, loctite) on the nuts/bolts. Did not want them to even think of coming loose!
Constantine
What have you seen as far as rivets in the different 928 model years? Were they stopped after a certain MY?
As far as the bolt conversion, I used locking washers and loctite (yes, loctite) on the nuts/bolts. Did not want them to even think of coming loose!
Constantine
Wow, I never gave it any thought as to which year had rivets or bolts. Porsche said loose drive plates on 1985 thru 1987 model cars can be repaired with bolts. Base on comments made, I guess Porsche would use what ever was in stock at that time.
On all of my rebuilt Transmissions I change the rivets and flange bearings as a normal rebuilt procedure, ever if the drive plate had bolts, I would install new ones. I use a lot of loctite, its better to be safe than sorry.
09-19-2007, 12:18 AM
#23
Team Owner
from that picture it looks like it has seem some movment between the flange and plate see the thin traces of rust colored dust from the flange/plate area
09-19-2007, 01:39 AM
#24
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Here's the bulletin. It's a bit distorted, but it's the only copy I have. Steve has the bolt PNs that are not legible below. It says "85-87" as if those were the only years.
09-19-2007, 03:13 AM
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Thanks everyone. I am just at that stage with my auto rebuild now. Good info.
Anyone have a good source on rebuilt torque converters. I seem to have hit a snag with that one. I am tempted to use the old one. There was no metal in the pan and when I cut the filter apart it was clean. It apears from the autopsy that the cause of problems was a bad O ring in the front pump. It was hard and split. The leak was not from the front seal as I had thought but from the o-ring breaking.
In the manual there is an adjustment on the valve body that will change the responsiveness in shifting. Has anyone played around with this?
Thanks
Dan the Pod Guy.
Anyone have a good source on rebuilt torque converters. I seem to have hit a snag with that one. I am tempted to use the old one. There was no metal in the pan and when I cut the filter apart it was clean. It apears from the autopsy that the cause of problems was a bad O ring in the front pump. It was hard and split. The leak was not from the front seal as I had thought but from the o-ring breaking.
In the manual there is an adjustment on the valve body that will change the responsiveness in shifting. Has anyone played around with this?
Thanks
Dan the Pod Guy.
09-19-2007, 10:28 AM
#26
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Bill,
Thats awesome and I was beginning to think it did not exist.
Lets see if we can get a perfect copy for all of us that want it.
Justin - of Justin who fame - has been doing a great job at finding TSB's so maybe with this copy he can come up with the actual TSB ib .pdf.
Thanks,
Roger
Thats awesome and I was beginning to think it did not exist.
Lets see if we can get a perfect copy for all of us that want it.
Justin - of Justin who fame - has been doing a great job at finding TSB's so maybe with this copy he can come up with the actual TSB ib .pdf.
Thanks,
Roger
09-19-2007, 10:32 AM
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Maybe after 87 they improved the riviting and stopped the problem.
Anyone out there changed out the rivits for bolts because of rattles after MY87???
Anyone out there changed out the rivits for bolts because of rattles after MY87???
09-19-2007, 09:40 PM
#29
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Thanks everyone. I am just at that stage with my auto rebuild now. Good info.
Anyone have a good source on rebuilt torque converters. I seem to have hit a snag with that one. I am tempted to use the old one. There was no metal in the pan and when I cut the filter apart it was clean. It apears from the autopsy that the cause of problems was a bad O ring in the front pump. It was hard and split. The leak was not from the front seal as I had thought but from the o-ring breaking.
In the manual there is an adjustment on the valve body that will change the responsiveness in shifting. Has anyone played around with this?
Thanks
Dan the Pod Guy.
Anyone have a good source on rebuilt torque converters. I seem to have hit a snag with that one. I am tempted to use the old one. There was no metal in the pan and when I cut the filter apart it was clean. It apears from the autopsy that the cause of problems was a bad O ring in the front pump. It was hard and split. The leak was not from the front seal as I had thought but from the o-ring breaking.
In the manual there is an adjustment on the valve body that will change the responsiveness in shifting. Has anyone played around with this?
Thanks
Dan the Pod Guy.
The pump o-ring does not affect the pumps ability to produce working pressure; it prevents residue oil from leaking out of the front of the transmission. Did you check the B2 piston like we spoke about.
09-20-2007, 04:35 AM
#30
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Steve,
Yes thanks much for your advice. I saw nothing wrong with the piston. Other rebuilders I taked to said they simply replace the teflon seals without any problems. I replaced the outer teflon seal, but the inner one from the kit I got was too big by just hair. Instead of triming to down in length I ordered a new one from Mercedes.
Since it appears I can replace the B2 piston from the outside without pulling the trans, I thought I would go with it and see what happens. All this is experimental anyways since this is the first time rebuilding an automatic. Given my past learning experience I expect to pull the transmission a few times before I get it right.
The B2 band looked to be in great shape. I measured all the tollerances on the clutches, but the new ones were the same as the old one. None of the steels were burned. The measurements on the two clutches was correct although with the new ones at the high end of the range. The space between the cover and the main clutches measured out right and I have the right amount of play in the front shaft - measured two different ways. I found nothing else damaged. All the needle bearing are in good shape. There was no metal traped in the filter when I cut it open.
The one concern I have is a little scoring on the front pump. The backing plate holding the gears in place was scarred a little. I polished it out.
All this is on a trans with 100K miles. I do not see anything that could be making a scaping or ticking sound I heard. I will do the bolt conversion on the flex plate and have already new bearings installed in the Torque tube.
The best I can figure is the trans started leaking faster than I expected and the fuild got low, although when I checked it the level was correct. Other than that one hard and split O ring inside the from pump housing I can see nothing else that looks bad.
I do have an 87 trans as a core. Is the B2 piston on that trans different from the 85? Is that one I can use as an upgrade if this does not work. The kit contained some parts i am not using including a wider teflon seal about the same size as the B2 piston.
I have not got to the valve body yet. I just glanced over the manual on the valve body, but will read it in more depth before I install it. There is a rebuild kit with new springs for the valve body on the internet which claimed to cure whatever problems valve bodies have. Any thing I should look at there before I clean it up and put it back together. Since the valve body can be removed from the trans while in the car I was just going to install it and worry later.
This thing came apart much easier than I expected. I am used to building manual transmissions and engaging a press to take the clusters apart. Nothing needed here other than the special spring compressor I made for the clutches. However, there are more rewarding tasks so if I get this one to go I am out of the automatic trans business forever. All my other 928s are five speeds.
Thanks again for you help and support.
Dan the Pod Guy.
Yes thanks much for your advice. I saw nothing wrong with the piston. Other rebuilders I taked to said they simply replace the teflon seals without any problems. I replaced the outer teflon seal, but the inner one from the kit I got was too big by just hair. Instead of triming to down in length I ordered a new one from Mercedes.
Since it appears I can replace the B2 piston from the outside without pulling the trans, I thought I would go with it and see what happens. All this is experimental anyways since this is the first time rebuilding an automatic. Given my past learning experience I expect to pull the transmission a few times before I get it right.
The B2 band looked to be in great shape. I measured all the tollerances on the clutches, but the new ones were the same as the old one. None of the steels were burned. The measurements on the two clutches was correct although with the new ones at the high end of the range. The space between the cover and the main clutches measured out right and I have the right amount of play in the front shaft - measured two different ways. I found nothing else damaged. All the needle bearing are in good shape. There was no metal traped in the filter when I cut it open.
The one concern I have is a little scoring on the front pump. The backing plate holding the gears in place was scarred a little. I polished it out.
All this is on a trans with 100K miles. I do not see anything that could be making a scaping or ticking sound I heard. I will do the bolt conversion on the flex plate and have already new bearings installed in the Torque tube.
The best I can figure is the trans started leaking faster than I expected and the fuild got low, although when I checked it the level was correct. Other than that one hard and split O ring inside the from pump housing I can see nothing else that looks bad.
I do have an 87 trans as a core. Is the B2 piston on that trans different from the 85? Is that one I can use as an upgrade if this does not work. The kit contained some parts i am not using including a wider teflon seal about the same size as the B2 piston.
I have not got to the valve body yet. I just glanced over the manual on the valve body, but will read it in more depth before I install it. There is a rebuild kit with new springs for the valve body on the internet which claimed to cure whatever problems valve bodies have. Any thing I should look at there before I clean it up and put it back together. Since the valve body can be removed from the trans while in the car I was just going to install it and worry later.
This thing came apart much easier than I expected. I am used to building manual transmissions and engaging a press to take the clusters apart. Nothing needed here other than the special spring compressor I made for the clutches. However, there are more rewarding tasks so if I get this one to go I am out of the automatic trans business forever. All my other 928s are five speeds.
Thanks again for you help and support.
Dan the Pod Guy.