Flywheel inspection pics...replace or resurface?
#16
Nordschleife Master
There is absolutely no doubt, that flywheel needs to be resurfaced; what does the pressure plate look like? There is no sense in going to this length and not fix it right. Take it to an automotive machine shop for resurfacing and also to check the condition of the rubber in the flywheel.
"Due to their design, LuK does not recommend resurfacing dual-mass flywheels."
"I've been able to drag my fingernail across the flywheel without snags."
I have looked and relooked at the photos , I do not see rivet marks and your "without snags" makes me wonder if others are seeing things that are not . I would not remove the flywheel or try to have it worked on . I would replace just about every other part . You have not said you had any problems with the flywheel . Your problem was a slipping clutch . I think a new pp and disc will solve that .
Last edited by Indycam; 10-23-2009 at 01:00 AM.
#17
Racer
Thread Starter
After looking at a light weight vs. dual mass comparison picture, I began to think that I may actually already have the lwf setup. I sent my pictures to a Porsche specialist here in Houston and he thinks I have the lwf as well after seeing them. I'll be able to remove the flywheel once my socket comes in but can anyone tell if I have the lwf by the pictures I posted?
Thanks,
Kyle
Thanks,
Kyle
#18
Rennlist Member
I will have to agree, the FW on your engine does not look like the dual mass fw. I just went out to the garage and checked my dual mass fw, here are some pictures, I also measured the width of the DM FW it may not show in the picture, but the measurement is just over 49 m/m.
#19
Rennlist Member
Steen's absolutely right, you've got a LWF, sorry I didn't catch it, results are still the same tho, pull it and have it checked and surfaced, if it's beyond help I'd grab the one in the for sale thread...
#21
Racer
Thread Starter
Thanks for the insight guys. This site is such an incredible resource of information! After reading all of the posts, I have come to this question:
Can a worn flywheel cause the clutch to slip?
If yes, then I will remove it and take it to a machine shop for their recommendation on replacement or resurfacing (although the Porsche dealer told me this couldn't be done).
If no, then I would like to leave it alone. I did the fingernail test again without any snags. There are no gooves or cuts in the flywheel...only the discolorations seen in the pictures.
I know worn out discs and pressure plates cause slippage and I am planning on replacing these since it was slipping. I know a worn out flywheel can cause chattering but I had no chattering at all...only slippage. I subscribe to the "don't fix it if it ain't broken" theory and I would prefer not to remove the flywheel if I can be certain that it is not what was causing the clutch to slip.
What does everyone think?
Thanks again for the help. The first time is always a learning process and I will feel much more confident about all of this next time I do it.
Kyle
Can a worn flywheel cause the clutch to slip?
If yes, then I will remove it and take it to a machine shop for their recommendation on replacement or resurfacing (although the Porsche dealer told me this couldn't be done).
If no, then I would like to leave it alone. I did the fingernail test again without any snags. There are no gooves or cuts in the flywheel...only the discolorations seen in the pictures.
I know worn out discs and pressure plates cause slippage and I am planning on replacing these since it was slipping. I know a worn out flywheel can cause chattering but I had no chattering at all...only slippage. I subscribe to the "don't fix it if it ain't broken" theory and I would prefer not to remove the flywheel if I can be certain that it is not what was causing the clutch to slip.
What does everyone think?
Thanks again for the help. The first time is always a learning process and I will feel much more confident about all of this next time I do it.
Kyle
#22
Rennlist Member
Kyle,
from the pics you posted the blued section, the inner third, looked scored, but it's hard to tell. If you put a metal straight edge across the FW and it is flat you are most likely fine. Shine a light on the backside of the edge and you'll get a good picture of the condition Scotchbright the surface clean and go. If there is a depression try fitting a feeler guage underneath. You will be looking for both the depth of the groove as well as the taper of the FW across the diameter. Since you had no vibration or chatter it's safe to assume the runout is ok. this is basically what they will do at the shop just with more precision...
A grooved or tapered flywheel or pressure plate will wear faster and not provide the same clamping force as a fresh setup. The disk will have to wear to bed itself into the irregularities. If you do put or back together with a grooved FW you'll want to go easy on it for a few thousand miles so not to slip the clutch and burn the disk.
In the end my humble advice is the same: If you are unsure as to the condition of it pull it off and take it to a machine shop and they will put it on the bench and measure it for you. Then you'll know and not be getting advice based on limited photos. It's ten bucks for the Allen and twenty minutes and then you have real info to make the call.
Good luck with it and kudos for wrenching on it yourself! Seems to be less and less these days. Let us know how it comes out.
from the pics you posted the blued section, the inner third, looked scored, but it's hard to tell. If you put a metal straight edge across the FW and it is flat you are most likely fine. Shine a light on the backside of the edge and you'll get a good picture of the condition Scotchbright the surface clean and go. If there is a depression try fitting a feeler guage underneath. You will be looking for both the depth of the groove as well as the taper of the FW across the diameter. Since you had no vibration or chatter it's safe to assume the runout is ok. this is basically what they will do at the shop just with more precision...
A grooved or tapered flywheel or pressure plate will wear faster and not provide the same clamping force as a fresh setup. The disk will have to wear to bed itself into the irregularities. If you do put or back together with a grooved FW you'll want to go easy on it for a few thousand miles so not to slip the clutch and burn the disk.
In the end my humble advice is the same: If you are unsure as to the condition of it pull it off and take it to a machine shop and they will put it on the bench and measure it for you. Then you'll know and not be getting advice based on limited photos. It's ten bucks for the Allen and twenty minutes and then you have real info to make the call.
Good luck with it and kudos for wrenching on it yourself! Seems to be less and less these days. Let us know how it comes out.
#23
Nordschleife Master
Yes a worn flywheel can cause slip .
If the flywheel is worn to the point where the disc is no longer being clamped
to the same psi as new ...
Your flywheel is no where near to being that worn .
It has another million or two miles to go until its that worn .
If the flywheel is worn to the point where the disc is no longer being clamped
to the same psi as new ...
Your flywheel is no where near to being that worn .
It has another million or two miles to go until its that worn .
#25
Wear limit on the clutch is 0.3 mm from the top of the rivet to the surface. 1.0mm when new. I'm abit confused when I remearsured my clutch which had at least 100km+ put on it by me alone and it was over 1.0mm so I assumed it was aftermarket and was thicker. I put it back in as it was nowhere near the 0.3 mm limit. As Indy indycated, flywheel resurfacing is a Porsche NoNo but I've heard of peeps doing it - although they may not have been dual mass which could interfer with the machining processes unless the process used to hold the flywheel is on the outer surface as opposed to the flexible inner portion. Possibly milling would work.
Bill
Bill
#26
Kyle,
Here is the name of a machine shop in Houston that was recommended by a local porsche dealership, just in case.
Keeland Automotive Machine - 713-664-9419
No connection - Did my 951 head sometime back.
Good luck with the clutch job.
biggles
Here is the name of a machine shop in Houston that was recommended by a local porsche dealership, just in case.
Keeland Automotive Machine - 713-664-9419
No connection - Did my 951 head sometime back.
Good luck with the clutch job.
biggles
#27
Racer
Thread Starter
Thanks for the recommendation Biggles. I ended up playing it safe and buying a new flywheel so I can get my car back together quickly without any worries. I am going to take the old flywheel in to see if it can be machined. Assuming it can, I will have a resurfaced flywheel available soon.
Kyle
Kyle