87 944 N/A Auto trans noise at bellhousing

[A_A_Ron]

So...I once again fell for the "mechanic" special with a German name attached to it...

As the title states, I have an 87 944 N/A with automatic tranny, approximately 150K miles. Recently, I started hearing this horrid knocking at idle. It happened in park, neutral, drive, reverse. When I accelerated out of the idle circuit, the noise went away. I crawled around under the car while it was running on jackstands with a mechanic stethoscope. Noise is definitely concentrated at the bellhousing area. I looked in the inspection hole and can see hairline cracks in the rubber on the damper plate. Assuming that is the culprit ATT. I probed around the torque tube and transaxle, but the sound is definitely coming from the bellhousing.

I understand a new damper plate is very expensive. I also read on a forum about a "static clutch conversion" for an automatic. Can someone enlighten me on this and can someone say from experience whether it is a viable solution?

Thanks in advance.

[FLYGEEZER]

Yep, you have a busted dampner....Best way outta this is to make a phone call to Ean @ 944online. He will have all the info & parts (used) required. I do remember ya gotta change the flywheel for a 5 speed then install a manual clutch sans the throw out bearing & attachments. My 944 is an auto & if I ever have to replace another high price dampner I will use Ean "fix". Good luck!

[Steve_M]

When my dampner blew out, it was cheaper to convert to manual (I had a parts car) by about $300.00; a lot of work, but it sure made a difference in how the car runs. Just a thought.

[A_A_Ron]

Guess I'll be calling 944online and look into the static clutch conversion option. Too bad I don't have a parts car lying around...

Thanks for the help!

[Slam]

A word about this: it's far easier to pull the motor to fix this than it is to drop the tranny and try to gut the car from underneath. I'm in the middle of it right now with my wife's 87, but converting flex damper to static clutch has wound up as a motor refresh too. Almost ready to put it back in... I'm planning to photograph the procedure and do a write-up. Lots of folks have gone this route but not posted a lot of pics or info. In our cAse we had the clutch parts from a dead car to work with so that part of the fix was free. The engine refresh, on the other hand, has really held us up.

[A_A_Ron]

Slam,
Thanks for the input! I'd really love to see the photos and write up.

[jeffrsmith]

Originally Posted by Slam

A word about this: it's far easier to pull the motor to fix this than it is to drop the tranny and try to gut the car from underneath. I'm in the middle of it right now with my wife's 87, but converting flex damper to static clutch has wound up as a motor refresh too. Almost ready to put it back in... I'm planning to photograph the procedure and do a write-up. Lots of folks have gone this route but not posted a lot of pics or info. In our cAse we had the clutch parts from a dead car to work with so that part of the fix was free. The engine refresh, on the other hand, has really held us up.

+10 - I dropped the engine to do an engine reseal and found that my damper had many cracks, bought the parts for the clutch conversion and it has worked fine since completion. Ian at 944online should be able to provide a parts package with everything you need to do this job.

[WizPorsche944]

I wonder if my problem is a busted dampner ? My 87 vibrates ( no knocking) really bad at idle in park and it goes away in gear

[jeffrsmith]

Could be a sign that it is on its way out. It may be that it has cracked and when not under load is allowing things to vibrate.

[djnolan]

If you have a bad vibration the damper may have already disintegrated. You can look inside the bell housing for rubber debris thru the timing hole on top or by removing the starter.

When mine let go there wasn't much warning. It disintegrated and rubber went everywhere inside, it made a racket, vibrated, but was able to limp home on the metal frame of the damper. That was about 5 years ago.

Now I have a knocking sound at cold idle. It could be the damper or torque tube, or maybe the exhaust. Since I depend on the car to get to work and not win races I just take it easy and hope for the best. I can't see a 5 year old damper disintegrating under light load.

[jeffrsmith]

djnolan - you say you can't see a "five year old damper" disintegrating? The problem with this is that although you may have only put the damper in five years ago, how long did the rubber age on the shelf?

Since the auto trans version of this car was not so popular, I doubt that there is much of a call for aftermarket on this part which could mean that although your damper is only five years old to you, it may well be 10 - 20 years old.

Slam - the most frustrating issue I had when putting the engine back in the car was getting the proper angle on the engine to get the torque tube shaft aligned properly, took two of us the better part of an hour jockeying the engine around with the leveler to finally get it to engage. Because we found that there is not much longitudinal space in the engine compartment we actually went in at a slight angle (pushing the TT sideways to meet the angle) - once we did this it went together in no time.

[jeffrsmith]

A_A_Ron - I bought the parts to do my conversion through people on this forum in the parts for sale section. I think I paid $150 for the flywheel, clutch, and pressure plate - you must have a flywheel from an 86 or newer. While doing the change on mine, I also replaced the rear main seal and pilot bearing. I used new flywheel and pressure plate bolts (IIRC the bolts that hold the damper on and the pressure plate bolts are different).

The clip that hold the damper in place can be a real PITA to get off. I believe if you use lock ring pliers and compress the clip you can move the damper just enough to clear the clip, then you can use the lock ring pliers to expand the clip to get it off the drive shaft like an normal lock ring.

[Slam]

Jeff, thanks for the install ti0. Did you have your bellhousing bolted to the motor or TT on install? We've got the rad out and the hood off to give us more room fore and aft.

About that snap ring... My 12-year-old son got it in less than 20 min. We studied PET and learned the key was removing the lock bolt from the drive shaft collar first. Then slide the remains of the flex damper to the rear, exposing the C-clip. By the time I was ready to go down to the shop and see how he was getting on, he had come back triumphantly carrying the dead flex disc. And he emphatically stated the bolt was NOT 6mm inner hex. 8?

[jeffrsmith]

Slam - We had the bellhousing attached to the engine, I did not want to have to deal with the upper bellhousing bolts once we got it back in the car. It also made it easier to get the speed and reference sensors properly gapped without having to fiddle with them in the car.

While you are working on this I would recommend that you cut the bellhousing where the speed and reference sensors mount so that if there is a next time for dropping engine or removing bellhousing you don't have to have to pull the sensors first.

[Slam]

Roger that. I also have an early large-frame starter standing by in case we get EMF problems after making the cut.

[A_A_Ron]

Unfortunately, Ian at 944Online is out of the parts for the static clutch conversion and doesn't know when he will get more. Any other ideas where I can source those parts?

[Slam]

How about someone right here on Pelican? You need flywheel, ring gear, pressure plate and clutch disc. Preferably from the same year car you're dismembering (although in our case we're using 85 parts in an 87 car). I'd suggest new flywheel bolts, PP bolts, pilot bearing and rear main seal WYIT. We plan to gt back to work on ours this weekend, if the weather plays nice.

[jeffrsmith]

Actually I bought my parts through a fellow Pelican, Ian did not have the parts available when I was doing my conversion. Have a look at the for sale section, when I found my parts they had been listed for about a year - I dropped the guy a PM and he still had the stuff.

[John_AZ]

Originally Posted by Slam

A word about this: it's far easier to pull the motor to fix this than it is to drop the tranny and try to gut the car from underneath. I'm in the middle of it right now with my wife's 87, but converting flex damper to static clutch has wound up as a motor refresh too. Almost ready to put it back in... I'm planning to photograph the procedure and do a write-up. Lots of folks have gone this route but not posted a lot of pics or info. In our cAse we had the clutch parts from a dead car to work with so that part of the fix was free. The engine refresh, on the other hand, has really held us up.

Originally Posted by A_A_Ron

Slam,
Thanks for the input! I'd really love to see the photos and write up.

Slam,
Great idea about the DIY.

A_A_Ron,
In your other recent post, why do you want to use a rubber puck clutch disc instead of the spring type?
EDIT: I found the answer on Ian's site. Use a rubber center disc.
I asked the question because most "old/used" rubber center disc are 20 years old or more unless you get lucky in buying a newer one.

J_AZ