Flex Plate "Save" Report
475hp/460lb.ft
03-27-2009, 08:19 PM
#32
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Hi Aryan,
Make sure the front flexplate clamp is not hanging up on the drive shaft splines. You should take out the pinch bolt completely and then using a large screw driver, or better yet a small pry bar, try flexing it back onto the splines. After letting it go it should rebound back to straight, if not that front flexpate should be changed out.
HTH,
Constantine
Make sure the front flexplate clamp is not hanging up on the drive shaft splines. You should take out the pinch bolt completely and then using a large screw driver, or better yet a small pry bar, try flexing it back onto the splines. After letting it go it should rebound back to straight, if not that front flexpate should be changed out.
HTH,
Constantine
03-27-2009, 08:22 PM
#33
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Hi Dan,
Yes it does happen, but very infrequently. Usually due to a clutch problem.
Urban legend has it that Mark Anderson had this happen when he experimented with aftermarket racing clutches back a years ago.
Constantine
Yes it does happen, but very infrequently. Usually due to a clutch problem.
Urban legend has it that Mark Anderson had this happen when he experimented with aftermarket racing clutches back a years ago.
Constantine
Last edited by Black Sea RD; 03-27-2009 at 10:28 PM.
03-28-2009, 10:01 AM
#34
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Make sure the front flexplate clamp is not hanging up on the drive shaft splines. You should take out the pinch bolt completely and then using a large screw driver, or better yet a small pry bar, try flexing it back onto the splines. After letting it go it should rebound back to straight, if not that front flexpate should be changed out.
03-28-2009, 07:19 PM
#35
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Would metal particles show up in Filter??
Just did spring oil change and filter and with all the discussion on TBF I was going to see if I could get under and check.
Couldn't get car high enough, plus spent too much time fighting with the belly pans, but thought that if I had TBF starting, it should show up as metal particles in oil and filter. ?? yes/no??
Opened old filter and nothing but oil and no particles in drained oil, am I safe?
Bob Voskian
1989 928 S4 silver/black (w/84,000 miles)
2006 BMW X% 3.0i
Couldn't get car high enough, plus spent too much time fighting with the belly pans, but thought that if I had TBF starting, it should show up as metal particles in oil and filter. ?? yes/no??
Opened old filter and nothing but oil and no particles in drained oil, am I safe?
Bob Voskian
1989 928 S4 silver/black (w/84,000 miles)
2006 BMW X% 3.0i
03-28-2009, 09:12 PM
#37
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Hi Bob,
You should look at your flexplate and see what's happening. As Chris said, metal particles seen in the oil means damage has already occurred.
A check should also be done of the rear pinch bolt as Mr. Merlin has often said.
The more you get familiar with your 928, the better for it and you!
Just do it safely, using jack stands to help support the car when underneath. Or find a local shop who can help you with this and start a friendly relationship with them. Might be helpful in the future for other matters.
Regards,
Constantine
You should look at your flexplate and see what's happening. As Chris said, metal particles seen in the oil means damage has already occurred.
A check should also be done of the rear pinch bolt as Mr. Merlin has often said.
The more you get familiar with your 928, the better for it and you!
Just do it safely, using jack stands to help support the car when underneath. Or find a local shop who can help you with this and start a friendly relationship with them. Might be helpful in the future for other matters.
Regards,
Constantine
03-29-2009, 09:38 AM
#40
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Hi Lionel,
Probably one of the best sites can be found through 928 International's website. 928 International is a Rennlist sponsor by the way. Once there, check out their links page. You'll see a site for Tony's site and there you'll find a pictorial on how to do the flexplate/TBF check. Tony's site also has a bunch more interesting how to stuff there for future projects too.
Hope that helps,
Constantine
Probably one of the best sites can be found through 928 International's website. 928 International is a Rennlist sponsor by the way. Once there, check out their links page. You'll see a site for Tony's site and there you'll find a pictorial on how to do the flexplate/TBF check. Tony's site also has a bunch more interesting how to stuff there for future projects too.
Hope that helps,
Constantine
03-29-2009, 10:45 AM
#43
Rennlist Member
When I first heard of the thrust bearing failure problem on S4 & later automatics, I started at least an annual check. The first and most importatn thing is to "get it right" first, by loosening the clamp, moving the flex plate/crank forward and back to check the end play, then to ~ the mid point and re-clamping (I use a new bolt, and torque it to 110% of the torque specification).
Then, to simplify future checking, I take some white touch up paint and paint the splines just ahead of the clamp - right back to the clamp. I usually turn the engine enough to get the paint all around the splined shaft. Then, each time I have the car on a hoist, or at least once a year or ~5K miles I use a light probe to check the clamp/spline. If I see ANY space between the clamp and the white paint on the spline, The clamping process will be re-done. However, over about 15-20K miles in each of 3 automatic cars ('87, '88, and '94)over the past 8 years, I have not seen ANY movement. The '88 was tracked in PCA Drivers Ed events for about 15 days a year, so had a LOT of wide open throttle accelerations. The other two were/are street driven only, 99% moderate accelerations.
Just my method of each checking. YMMV (Your Method May Vary)!!!! - Ha.
Gary Knox
West Chester, PA
Then, to simplify future checking, I take some white touch up paint and paint the splines just ahead of the clamp - right back to the clamp. I usually turn the engine enough to get the paint all around the splined shaft. Then, each time I have the car on a hoist, or at least once a year or ~5K miles I use a light probe to check the clamp/spline. If I see ANY space between the clamp and the white paint on the spline, The clamping process will be re-done. However, over about 15-20K miles in each of 3 automatic cars ('87, '88, and '94)over the past 8 years, I have not seen ANY movement. The '88 was tracked in PCA Drivers Ed events for about 15 days a year, so had a LOT of wide open throttle accelerations. The other two were/are street driven only, 99% moderate accelerations.
Just my method of each checking. YMMV (Your Method May Vary)!!!! - Ha.
Gary Knox
West Chester, PA
06-29-2009, 05:01 PM
#44
Team Owner
I just reread this thread, and there is no mention of checking the rear pinch bolt on the drive shaft.
My suggestion is that if your checking you car for the first time then this must be done.
It requires the exhaust and the center heat shield to be dropped down, once the front clamp is loose then remove the rear clamp bolt and check its shank for wear marks indicating that it wasnt tight and the driveshaft is moving in the rear clamp.
If the bolt looks good then add some blue loctite to the threads and then install it torque to 66ft/lbs then go to the front and pry the flywheel back then install the front clamp bolt the same way as the rear was installed .
Note that when loosening the rear bolt you may find that the bolt was just snugged tight, i have found more than a few rear pinch bolts loose compared to the 66ft/lb
My suggestion is that if your checking you car for the first time then this must be done.
It requires the exhaust and the center heat shield to be dropped down, once the front clamp is loose then remove the rear clamp bolt and check its shank for wear marks indicating that it wasnt tight and the driveshaft is moving in the rear clamp.
If the bolt looks good then add some blue loctite to the threads and then install it torque to 66ft/lbs then go to the front and pry the flywheel back then install the front clamp bolt the same way as the rear was installed .
Note that when loosening the rear bolt you may find that the bolt was just snugged tight, i have found more than a few rear pinch bolts loose compared to the 66ft/lb
07-03-2009, 01:28 AM
#45
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If you don't check the rear pinch bolt, it might very well sound like nuts and bolts rattling 'round in a soup can the next time you start and idle the car. It's a very interesting experience. Also, the rear pinch bolt is accessible only through a hole in the tube that is exposed when you crank the crankshaft bolt by hand, IIRC. It's time for me to do this again, but I've driven my 87 S4 auto only 4K in four years and 1,800 of that was 2006 SITM. The last time I checked it was before that trip. I suppose it's time. More than that, it's probably time for a water pump/tensioner rebuild/timing belt change.