Crankshaft seized after Trans Repair
08-21-2005, 03:22 PM
#31
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Not sure how it works down under.... but in the states, if they did work without having your signature on a work order, they would be on very thin ice, and would likely have to eat it. I hope you have a good lawyer...
08-21-2005, 04:08 PM
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Victim,
You should not be revaling any of the information given to you by tails to the Porsche people in Melbourne. Your lawyer should, upon discovery, determine whether the workshop had access to and used the service bulletin. They should not be told what they SHOULD have done, it should be made incumbent upon them to tell what they DID do in a court of law and then compare that to the correct standard.
You should be looking for a lawyer who is familiar with engineering principles and who is technically savvy and experienced.
You should not be revaling any of the information given to you by tails to the Porsche people in Melbourne. Your lawyer should, upon discovery, determine whether the workshop had access to and used the service bulletin. They should not be told what they SHOULD have done, it should be made incumbent upon them to tell what they DID do in a court of law and then compare that to the correct standard.
You should be looking for a lawyer who is familiar with engineering principles and who is technically savvy and experienced.
08-21-2005, 05:21 PM
#33
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Unfortunately, I know of nothing that could be called definitive to help you. Porsche has generally buried their heads in the sand regarding this. In fact, the description in the WSM pertains to pre-85 only, decribing the pre-load adjustment with shims, and including a statement that indicates on page 39-141 "Parts are deleted as of MY ‘85. Adjustment of the driver plate (including pre-1985 models) is no longer required."
Also, they include the following:
"To avoid axial pressure on crankshaft and crankshaft thrust bearings, the connections between flywheel and drive plate (distance X) must be checked and adjusted after replacement
of engine, flywheel or central tube. This adjustment is not necessary after replacement of transmission or transmission parts."
Ugh. This is not really true depending on how the work was done, but I'm not qualified to comment.
Here is further discussion that may or may not help you:
http://www.nichols.nu/tip598.htm
http://home.wxs.nl/~Jennit/Technical...ingFailure.htm
Also, they include the following:
"To avoid axial pressure on crankshaft and crankshaft thrust bearings, the connections between flywheel and drive plate (distance X) must be checked and adjusted after replacement
of engine, flywheel or central tube. This adjustment is not necessary after replacement of transmission or transmission parts."
Ugh. This is not really true depending on how the work was done, but I'm not qualified to comment.
Here is further discussion that may or may not help you:
http://www.nichols.nu/tip598.htm
http://home.wxs.nl/~Jennit/Technical...ingFailure.htm
08-21-2005, 06:34 PM
#34
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Vic,
From our first meeting on the Porsche 928 Message Board, I responded ...
" Subject: Re: Crankshaft seized after trans rebuild (40 views)
Message: We have written much about thrust bearing failure and you can access this in the Rennlist 928 forum archives - https://rennlist.com/forums/928-forum-69/.
The block is frequently destroyed as a consequence of two primary mechanisms in predominately '87 and up autos. The first category is of a slow and progressive forward 'creep' of the front flexplate along the splined prop shaft within the torque tube: a typical amount is 3mm, and begins the process by consuming a normal crank end float ( 0.1mm to 0.4mm). The thrust bearing erodes, then the block as the engine begins to stall when warm, bad, badder, worse, seized! .... this can be accommodated by periodic release of the pinch bolt which allows the front flex plate to retreat and allows the crank to 'float' as designed. Retorque to 65 ft.lbs. and check every year or so.
The second category occurs when someone who doesn't know their [Oops!] **from their elbow reinstalls a transmission: this pretty much covers your situation described above.
When the transmission is reinstalled, the rear flex plate has a similar coupling that spline locks to the drive/prop shaft - with one significant difference: the pinch bolt for the rear must also fit into a circumferential groove cut into the splines. This provides the 'reference' location for the reinstall.
The FINAL step is to assure that the front flex plate was released - and ONLY locked down as the absolutely LAST STEP! This is the only guarantee to assure that the necessary crank end float is preserved. A different torque convertor could cause a dimensional change - so if the rear is correctly fitted in the groove, the difference must be corrected at the front flex plate ....
If you dealership faulted on this essential step, IMHO, they owe you an engine - and a bill proportional to a normal xmission O/H."
** this reads better when '***' is substituted for 'oops' darn finikey moderators ...
The dialogue has advanced through the expertise of many kind rennlisters.
Regrettably ( not for Porsche), the elements that constitute good engineering practice and the empirical wisdom gained through witness to TBF disasters has not apparently been committed to paper by the manufacturer. The sole '***** in the armour' would appear to be the suggested allowance of increasing the pinch bolt torque by 10% ... by Porsche, and the Tech bulletin #9203 earlier mentioned.
The 'good engineering practice' is that exercised by thinking, capable, and experienced men in the trade - you have heard from Steve Cattaneo:
quote "This is the only bulletin addressing thrust bearing failure. It does not mention transmission installation, we know from experience that the front clamping bolt should be loosen after or before installation of a transmission to relieve any crankshaft load on the TB." - end quote
Your dealership have clearly stated categorically they DID NOT do this ( re release of tension). As Porsche ag have apparently not advised their dealerships of revisions to the 1984 publication WSM 39-141 , your Dealer is hanging his case on that statement.
You are now left in the position of sourcing Expert Witness testimony to state the contrary - namely the need to release the front pinch bolt to mitigate TBF potential whenever Auto transmission reinstall occurs.
I'd love a trip to Oz to help - unfortunately, I'm not an expert in that field; however, I have enough expertise to suggest that that is what may help. Hope you can source an Expert.
__________________
From our first meeting on the Porsche 928 Message Board, I responded ...
" Subject: Re: Crankshaft seized after trans rebuild (40 views)
Message: We have written much about thrust bearing failure and you can access this in the Rennlist 928 forum archives - https://rennlist.com/forums/928-forum-69/.
The block is frequently destroyed as a consequence of two primary mechanisms in predominately '87 and up autos. The first category is of a slow and progressive forward 'creep' of the front flexplate along the splined prop shaft within the torque tube: a typical amount is 3mm, and begins the process by consuming a normal crank end float ( 0.1mm to 0.4mm). The thrust bearing erodes, then the block as the engine begins to stall when warm, bad, badder, worse, seized! .... this can be accommodated by periodic release of the pinch bolt which allows the front flex plate to retreat and allows the crank to 'float' as designed. Retorque to 65 ft.lbs. and check every year or so.
The second category occurs when someone who doesn't know their [Oops!] **from their elbow reinstalls a transmission: this pretty much covers your situation described above.
When the transmission is reinstalled, the rear flex plate has a similar coupling that spline locks to the drive/prop shaft - with one significant difference: the pinch bolt for the rear must also fit into a circumferential groove cut into the splines. This provides the 'reference' location for the reinstall.
The FINAL step is to assure that the front flex plate was released - and ONLY locked down as the absolutely LAST STEP! This is the only guarantee to assure that the necessary crank end float is preserved. A different torque convertor could cause a dimensional change - so if the rear is correctly fitted in the groove, the difference must be corrected at the front flex plate ....
If you dealership faulted on this essential step, IMHO, they owe you an engine - and a bill proportional to a normal xmission O/H."
** this reads better when '***' is substituted for 'oops' darn finikey moderators ...
The dialogue has advanced through the expertise of many kind rennlisters.
Regrettably ( not for Porsche), the elements that constitute good engineering practice and the empirical wisdom gained through witness to TBF disasters has not apparently been committed to paper by the manufacturer. The sole '***** in the armour' would appear to be the suggested allowance of increasing the pinch bolt torque by 10% ... by Porsche, and the Tech bulletin #9203 earlier mentioned.
The 'good engineering practice' is that exercised by thinking, capable, and experienced men in the trade - you have heard from Steve Cattaneo:
quote "This is the only bulletin addressing thrust bearing failure. It does not mention transmission installation, we know from experience that the front clamping bolt should be loosen after or before installation of a transmission to relieve any crankshaft load on the TB." - end quote
Your dealership have clearly stated categorically they DID NOT do this ( re release of tension). As Porsche ag have apparently not advised their dealerships of revisions to the 1984 publication WSM 39-141 , your Dealer is hanging his case on that statement.
You are now left in the position of sourcing Expert Witness testimony to state the contrary - namely the need to release the front pinch bolt to mitigate TBF potential whenever Auto transmission reinstall occurs.
I'd love a trip to Oz to help - unfortunately, I'm not an expert in that field; however, I have enough expertise to suggest that that is what may help. Hope you can source an Expert.
__________________
Last edited by Garth S; 08-21-2005 at 08:48 PM.
08-21-2005, 10:23 PM
#35
Your asked whether there are any more 'black and white' bulletins regarding the clearance of 'A' and 'X' in existance? I believe that all the bulletins issued by Porsche have been mentioned in the previous posts, however, there is also a lot of information contained in the WSM and especially in the acrhives of the Rennlist forum posts, that also have been mentioned. Using all this information you should be able to build a technically sound case, however, as previously stated Porsche Factory has played down the forward drive shaft clamp creap of the central tube drive shaft as applying pressure in the crankshaft thrust bearing very close to their chest.
Also previously mentioned, any thrust bearing failures from this source would not be treated as a warranty item by Porsche. This I believer is a nice way of saying to the the private Porsche approved dealerships of the past, that there is a known problem here lads, so if you if don't do the right thing upon reinstallation of anything to do with the central tube unit (that is a single bolted up unit of engine, central tube and the automatic gearbox with transaxle) and there is a thrust bearing failure in the engine then your workshop will wear the cost, not Porsche Germany.
To compound this problem of warranty on repairs, as you are aware, it is only recently that the Porsche dealerships have come under the fold of Porsche as Porsche Official Service Centres. Previously they were under private dealerships (Hamiltons in Melbourne) and warrany on Porsche approved repairs was ultimately passed back to Porsche for payment. This is most probably the reason for the issue of this bulletin mentioned above in the first place to stop the warranty of any bad carried out repairs by these private (Porsche Approved) dealerships being passed back to Porsche.
PCM, in this instance may have carried this over this directive into your argument, as a possible way of not honouring a warranty for their repair work.
What warranty did Porsche Centre Melbourne give on the work undertaken ? If they did give a warranty on their work, then this is possibly the nub of the problem. I would suggest that they are trying very hard to separate the engine failure from the automatic gear box repair, however, the automatic gearbox refit is inextricably linked as the engine via the central tube, as is one unit with specific clearance to be set up with specific step procedures on reassembly as detailed in the WSMs and bulletins.
I would suggest that this problem is well known within the Porsche network and the Porsche technicians have most probably been advised "verbally" with very little committed to writing to this affect, that any fault during reassembly can be extremely costly to Porsche, as it now has no middle dealerships to lay the cost off onto. It looks like you are now caught in the middle with extreme pressure being applied (you are between the rock and the hard place).
In closing you need to take a step back from the immediate problem and have a cold hard look at what has been said and develop a strategy on how you are going to deal with this problem.
I would suggest that you go to mediation, mutually agreed by both parties, with proof of evidence shared to seek a conclusion. If the lawyers get involved yours will most probably defend you to the limit of your resouces with their costs involved without fully understanding the technical issues.
I would suggest you contact Mr Ron Salter c/o Phillips Fox Solicitors, 120 Collins Street Melbourne, he has just left Phillips Fox to start up his own consultancy in Mediation and Arbitration, however he is still working out of their offices 3 days a week. He may be willing to give you some good advice, as he as been a Transportation Lawyer for many year and understands technical issues. I have no financial connection with Ron, I have known him in the business for many years.
Tails 1990 928 S4 Auto
Also previously mentioned, any thrust bearing failures from this source would not be treated as a warranty item by Porsche. This I believer is a nice way of saying to the the private Porsche approved dealerships of the past, that there is a known problem here lads, so if you if don't do the right thing upon reinstallation of anything to do with the central tube unit (that is a single bolted up unit of engine, central tube and the automatic gearbox with transaxle) and there is a thrust bearing failure in the engine then your workshop will wear the cost, not Porsche Germany.
To compound this problem of warranty on repairs, as you are aware, it is only recently that the Porsche dealerships have come under the fold of Porsche as Porsche Official Service Centres. Previously they were under private dealerships (Hamiltons in Melbourne) and warrany on Porsche approved repairs was ultimately passed back to Porsche for payment. This is most probably the reason for the issue of this bulletin mentioned above in the first place to stop the warranty of any bad carried out repairs by these private (Porsche Approved) dealerships being passed back to Porsche.
PCM, in this instance may have carried this over this directive into your argument, as a possible way of not honouring a warranty for their repair work.
What warranty did Porsche Centre Melbourne give on the work undertaken ? If they did give a warranty on their work, then this is possibly the nub of the problem. I would suggest that they are trying very hard to separate the engine failure from the automatic gear box repair, however, the automatic gearbox refit is inextricably linked as the engine via the central tube, as is one unit with specific clearance to be set up with specific step procedures on reassembly as detailed in the WSMs and bulletins.
I would suggest that this problem is well known within the Porsche network and the Porsche technicians have most probably been advised "verbally" with very little committed to writing to this affect, that any fault during reassembly can be extremely costly to Porsche, as it now has no middle dealerships to lay the cost off onto. It looks like you are now caught in the middle with extreme pressure being applied (you are between the rock and the hard place).
In closing you need to take a step back from the immediate problem and have a cold hard look at what has been said and develop a strategy on how you are going to deal with this problem.
I would suggest that you go to mediation, mutually agreed by both parties, with proof of evidence shared to seek a conclusion. If the lawyers get involved yours will most probably defend you to the limit of your resouces with their costs involved without fully understanding the technical issues.
I would suggest you contact Mr Ron Salter c/o Phillips Fox Solicitors, 120 Collins Street Melbourne, he has just left Phillips Fox to start up his own consultancy in Mediation and Arbitration, however he is still working out of their offices 3 days a week. He may be willing to give you some good advice, as he as been a Transportation Lawyer for many year and understands technical issues. I have no financial connection with Ron, I have known him in the business for many years.
Tails 1990 928 S4 Auto
08-22-2005, 03:49 PM
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Hi All. Garth you might have to. As the story went, a week or so ago the dealership GM wrote to say, please do not contact us anymore for our solicitors will introduce themselves. Just as intriguing, they recently called the independ engineering assessor (employed by me) to invite him back for more chit chat the aim of which,I presume, is to strengthen their case. But I could be wrong..I plan to schedule it in a couple weeks as by that time I would've hopefully absorbed and digested some of your ponderings and armed myself with the much talked-about JM's collection of publications. Thanks Jim, don't forget to mark the pages with post-it labels... Who knows, it might even be helpful to the shop.
Yes I have often stepped back, Tails, and I asked the question : why are they trying so hard to deny any wrong-doing, to the extent of calling me a liar ( someone had worked on your engine) and an ingrate ( look at it this way, we kindly fixed your car and you refused to pay ) and sticking fast to their guns ( if we made a mistake we would admit it ).
And I often asked, why me? Others have had the unfortunate same problem but their w'shop owned up and eventually paid up. But I've heard of the nightmare-months scenario and insurance refusing payment at last minute.
Out of the listings I have met honest guys. Guys of integrity and a sense of brotherhood. People who want to help. Strangers who offered to meet up and assist. Right here in Melb. Out there on the other side.
I think about losing the car, telling them to take it and stick it. I invested in prestige and integrity for peace of mind but got none.. But the guys; you guys make me believe.. As Garth had said happier days will be mine. I have barely begun.Up till now there have been hardly any technical discussion with the repairers.
And that mostly because the answers they gave me, I thought were audaciously bizzarre. Like, the drive shaft does not move. ( although two in the SAME building told me they did move, and easily).
Like, when I pointed out that six months prior to the trans repair ( nine months prior to crankshaft seizure) the sump was removed and drained, Hence if they were right that the bearing was wearing over time from previous work, wouldn't they see it in the oil? In the sump? No, they said. The shavings dropped into the bell housing so one couldn't see it. I could see him making up the excuses...
Time, I said, is truth. I am just warming up. Regards, Michael.
Last edited by victim; 10-16-2005 at 08:44 AM.
08-22-2005, 04:04 PM
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Question Guys,
Many of you mentioned relieving the flex plate, finding the null point, by releasing the clamp bolt (and doing it last). Is there a tech note requiring zoro preload? cos from my reading of earlier notes (39- 51 ) clearly a preload of 0.3 + 0.2 was required in the shim (earlier) design. But didn't that do harm to the thrust bearing? Was this clearance changed? To zero? Please fill me in.
Regards, Michael
Many of you mentioned relieving the flex plate, finding the null point, by releasing the clamp bolt (and doing it last). Is there a tech note requiring zoro preload? cos from my reading of earlier notes (39- 51 ) clearly a preload of 0.3 + 0.2 was required in the shim (earlier) design. But didn't that do harm to the thrust bearing? Was this clearance changed? To zero? Please fill me in.
Regards, Michael
08-22-2005, 05:31 PM
#38
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Michael,
a quick point: if you correctly quoted the dealership , "The shavings dropped into the bell housing so one couldn't see it.", that is another strange and unbelievable comment. TBF 'droppings' occur in the sump - and can be verified by both draining the oil and dissecting the oil filter of its outer can.
Had shavings dropped in the lower bellhousing, the flexplate must have been physically forced against the flywheel: under no stretch of the imagination can I foresee that ocurring under any operating condition. That takes us back to improper installation along the several possibilities previously mentioned.
Also, an examination of the flexplate may well shed insight on the failure mode. Any distortion of and/or errosion of its front face would suggest a colission unexpected from normal rotation .... leaving the potential of an axial force = improper assembly.
Lastly, you are correctly quoting the WSM regards the 'null point' of the front flexplate pinch collar. What I did, and I suspect many others do, is relax the pinch bolt and determine the crankshaft end float. It was a nominal 0.1mm IIRC: leaving the crank in the rearward position, the pinch bolt was torqued and a reference measure taken ( think I sent you a photo?). The 0.1 is insignificant to the prior 3.15mm movement of the flexplate. .... so at least I was unconcerned about the 0.3+.2 statement. Just an amateur on the loose
a quick point: if you correctly quoted the dealership , "The shavings dropped into the bell housing so one couldn't see it.", that is another strange and unbelievable comment. TBF 'droppings' occur in the sump - and can be verified by both draining the oil and dissecting the oil filter of its outer can.
Had shavings dropped in the lower bellhousing, the flexplate must have been physically forced against the flywheel: under no stretch of the imagination can I foresee that ocurring under any operating condition. That takes us back to improper installation along the several possibilities previously mentioned.
Also, an examination of the flexplate may well shed insight on the failure mode. Any distortion of and/or errosion of its front face would suggest a colission unexpected from normal rotation .... leaving the potential of an axial force = improper assembly.
Lastly, you are correctly quoting the WSM regards the 'null point' of the front flexplate pinch collar. What I did, and I suspect many others do, is relax the pinch bolt and determine the crankshaft end float. It was a nominal 0.1mm IIRC: leaving the crank in the rearward position, the pinch bolt was torqued and a reference measure taken ( think I sent you a photo?). The 0.1 is insignificant to the prior 3.15mm movement of the flexplate. .... so at least I was unconcerned about the 0.3+.2 statement. Just an amateur on the loose
08-22-2005, 07:34 PM
#39
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Earlier I indicated that the Porsche WSM simply said the pre-load adjustment is no longer needed since the deletion of the shim and clip in 85 and I could not find any bulletins to the contrary after reviewing the Morehouse CDs I have. Most of us here check and adjust the flexplate occasionally and believe it has to be checked when the tranny is replaced (frankly I don't know how you install the tranny without having this clamp loose), but Porsche does not appear to have said this anywhere.
Originally Posted by victim
Question Guys,
Many of you mentioned relieving the flex plate, finding the null point, by releasing the clamp bolt (and doing it last). Is there a tech note requiring zoro preload? cos from my reading of earlier notes (39- 51 ) clearly a preload of 0.3 + 0.2 was required in the shim (earlier) design. But didn't that do harm to the thrust bearing? Was this clearance changed? To zero? Please fill me in.
Regards, Michael
Many of you mentioned relieving the flex plate, finding the null point, by releasing the clamp bolt (and doing it last). Is there a tech note requiring zoro preload? cos from my reading of earlier notes (39- 51 ) clearly a preload of 0.3 + 0.2 was required in the shim (earlier) design. But didn't that do harm to the thrust bearing? Was this clearance changed? To zero? Please fill me in.
Regards, Michael
08-23-2005, 09:58 AM
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Hi Garth,
Just been talking about flywheel damage tonight. Another owner right here in Melb had the same TBF after Tran repair. He won.
I'm a step closer...
Cheers Mate
Just been talking about flywheel damage tonight. Another owner right here in Melb had the same TBF after Tran repair. He won.
I'm a step closer...
Cheers Mate
08-24-2005, 06:35 AM
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Hi All
Jim you mentioned it is pretty obvious thet must check preload on installation ( of trans ) but is it in black and white or is it implied. Their argument is that NOTHING moves i.e. the drive shaft doesn't move and if nobody touches it they'll simply bolt the coupling back in the same spot in the grooves. What is the preload - .3+.2?
A mechanic told me today that one would need to physically hand crank the engine one rev to be sure 9 this is described in Richard Andrade's paper which he kindly sent me ) but is it implied in the manuals? Again is this preload zero or 0.3 ?
Question : If the preload was huge say 10 mm as they claim would drive shaft move freely rearwards as suggested by various postings?
To answer your question Iceman, this will eventually go to a tribunal. But even if I won there's still the engine question : is it repaired / reparable ?
Thanks Guys
Michael
Jim you mentioned it is pretty obvious thet must check preload on installation ( of trans ) but is it in black and white or is it implied. Their argument is that NOTHING moves i.e. the drive shaft doesn't move and if nobody touches it they'll simply bolt the coupling back in the same spot in the grooves. What is the preload - .3+.2?
A mechanic told me today that one would need to physically hand crank the engine one rev to be sure 9 this is described in Richard Andrade's paper which he kindly sent me ) but is it implied in the manuals? Again is this preload zero or 0.3 ?
Question : If the preload was huge say 10 mm as they claim would drive shaft move freely rearwards as suggested by various postings?
To answer your question Iceman, this will eventually go to a tribunal. But even if I won there's still the engine question : is it repaired / reparable ?
Thanks Guys
Michael
08-24-2005, 07:25 AM
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Hi Michael ,
There are so many good replies on this thread I did not want to post anything but will at this point to try to help out too. I have done a study of this problem a few years back and I came up with some interesting findings.
1. The manuals say that the LAST step to be done after a TT/trans R&R is to torque down the pinch bolt at the front coupler. The shims/preload adjustment has been discontinued sometime in 1984. No preload is used currently.
2. Relieving the tension of the front flexplate periodically (once a year as suggested) is not acceptable since a forward push can be seen within a few hundred miles after doing the procedure. It's dependent on driving style and how worn the front coupler has become. This procedure would not even constitute a "band-aid" fix IMHO.
3. Torquing the front pinch bolt, even a new one, to the higher torque value as prescribed by some, had no effect in my tests on how much pressure was needed to push the driveshaft through the coupler. The PSI needed for movement of the driveshaft was the same as a old pinch bolt torqued to the standard setting.
4. This whole higher torque value for the pinch bolt was started years ago by a post wherein a fellow Rennlister overseas had his mechanics ask Porsche mechanics about the forward creep noticed in his 928S4. The Porsche mechanics prescribed a *change out* of the front flexplate and a higher torque setting of approximatly 10% on a new pinch bolt. Since changing the flexplate is costly and a hassle, that part of the overall prescription has been forgotten.
Good luck with your problem. It will be a battle for you with the mechanic shop but from the posts you've received you have a lot of ammunition to help you out. A copy of the manuals will help you too.
Good luck,
Constantine
[
There are so many good replies on this thread I did not want to post anything but will at this point to try to help out too. I have done a study of this problem a few years back and I came up with some interesting findings.
1. The manuals say that the LAST step to be done after a TT/trans R&R is to torque down the pinch bolt at the front coupler. The shims/preload adjustment has been discontinued sometime in 1984. No preload is used currently.
2. Relieving the tension of the front flexplate periodically (once a year as suggested) is not acceptable since a forward push can be seen within a few hundred miles after doing the procedure. It's dependent on driving style and how worn the front coupler has become. This procedure would not even constitute a "band-aid" fix IMHO.
3. Torquing the front pinch bolt, even a new one, to the higher torque value as prescribed by some, had no effect in my tests on how much pressure was needed to push the driveshaft through the coupler. The PSI needed for movement of the driveshaft was the same as a old pinch bolt torqued to the standard setting.
4. This whole higher torque value for the pinch bolt was started years ago by a post wherein a fellow Rennlister overseas had his mechanics ask Porsche mechanics about the forward creep noticed in his 928S4. The Porsche mechanics prescribed a *change out* of the front flexplate and a higher torque setting of approximatly 10% on a new pinch bolt. Since changing the flexplate is costly and a hassle, that part of the overall prescription has been forgotten.
Good luck with your problem. It will be a battle for you with the mechanic shop but from the posts you've received you have a lot of ammunition to help you out. A copy of the manuals will help you too.
Good luck,
Constantine
[
08-24-2005, 09:22 AM
#43
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Constantine,
More valuable input .
In point 1., you indicate the issue I cannot find in my 8 vol WSM set ( perhaps it is in the latter 9 vol set?): namely " The manuals say that the LAST step to be done after a TT/trans R&R is to torque down the pinch bolt at the front coupler".
This is precisely the statement made to Michael at the beginning - but I cannot support that by anything located in any factory documentation. Could you please provide a page reference?
Under point 2., regards the suggestion of checking the flex plate annually, I would be the guilty party
: admitted, it is an arbitrary statement - based on 3 observations at the start/middle/end points of a 2 year window. As most cars had likely never been examined at all in their first 15 years of life, I thought annually would be a significant improvement. Having applied the "#290" fix as advanced by Earl G. no movement has been observed in that period - measured to the hundredth of a mm.
Your point is well taken - that if the collar/shaft splines are worn, then no amount of torque will prevent migration: Such migration clearly occurs on new components - so some frequency of exam is in order .... but what interval ... ?
The penultimate redesign of this deficient coupling is the collet collar you have designed!!
More valuable input
.In point 1., you indicate the issue I cannot find in my 8 vol WSM set ( perhaps it is in the latter 9 vol set?): namely " The manuals say that the LAST step to be done after a TT/trans R&R is to torque down the pinch bolt at the front coupler".
This is precisely the statement made to Michael at the beginning - but I cannot support that by anything located in any factory documentation. Could you please provide a page reference?
Under point 2., regards the suggestion of checking the flex plate annually, I would be the guilty party
: admitted, it is an arbitrary statement - based on 3 observations at the start/middle/end points of a 2 year window. As most cars had likely never been examined at all in their first 15 years of life, I thought annually would be a significant improvement. Having applied the "#290" fix as advanced by Earl G. no movement has been observed in that period - measured to the hundredth of a mm. Your point is well taken - that if the collar/shaft splines are worn, then no amount of torque will prevent migration: Such migration clearly occurs on new components - so some frequency of exam is in order .... but what interval ... ?
The penultimate redesign of this deficient coupling is the collet collar you have designed!!
08-24-2005, 10:55 AM
#44
Supercharged
Rennlist Member
Rennlist Member
Join Date: May 2002
Location: Back in Michigan - Full time!
Posts: 18,925
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35 Posts
Victim-
I was looking throught he electronic service proceedures and bulletins to see if I could find ANYTHIGN to strengthen your case. Unfortunately, I could not find much. Here' what I did find. I don't think it weakens your case, but it really doesn't support it much either.
I was looking throught he electronic service proceedures and bulletins to see if I could find ANYTHIGN to strengthen your case. Unfortunately, I could not find much. Here' what I did find. I don't think it weakens your case, but it really doesn't support it much either.
