I got my Torque converter rebuilt with increased stall
09-01-2006, 10:48 AM
#18
Rennlist Member
Thread Starter
I will be generating slightly more heat. Do any of you think I should add a secondary Trans cooler to the system? I have no idea how good or not good the stock system is.
I got the trans stabbed last night, TT hooked up, pinch bolt installed, all the trans hook-ups completed. I'm ready to install the suspension now. I will need to post a pic of the "special tool" I fabricated which holds the suspension up level with the floor using my floor jack. Should make installing the suspension by yourself much much easier.
I got the trans stabbed last night, TT hooked up, pinch bolt installed, all the trans hook-ups completed. I'm ready to install the suspension now. I will need to post a pic of the "special tool" I fabricated which holds the suspension up level with the floor using my floor jack. Should make installing the suspension by yourself much much easier.
09-01-2006, 06:54 PM
#19
Originally Posted by SeanR
Hey Mike,
Did it fix the marbles?
Did it fix the marbles?
Hey? Answer the question dude...... Or am I already on your ignore list?
09-01-2006, 10:18 PM
#20
Captain Obvious
Super User
Super User
Originally Posted by SeanR
Hey? Answer the question dude...... Or am I already on your ignore list?
Let him finsh it first.
09-01-2006, 11:41 PM
#21
Originally Posted by Imo000
DUDE...the car is still in pieces! Let him finsh it first.
Let him finsh it first.
We know each other.
09-05-2006, 02:00 AM
#22
Rennlist Member
Thread Starter
Fired it up tonight. Still have the marbles. Exact same noise. No improvement since the beginning of this epic. I am this close "_" to....
Lets review.
1. New (rebuilt) Torque tube.
2. New TQ converter bearings (both of them)
3. Rebuilt Torque converter.
4. Rivets in rear flex plate tack welded into place.
5. Brand new Torque converter bolts.
I jacked the motor up off the shot engine mounts to make sure that was not creating a rattling noise. No improvement. The only things left are a section called "B-3" inside the transmission that I found mention of in the shop manuals (Transmission volume II in section 38 if I recall) regarding a rattling noise at 1500rpm, or, possibly a defective rebuilt torque tube. Mine rattles at idle in park or nuetral mostly, but will rattle in gear if I hit a certain RPM when decelerating (any time the drivetrain is not under load basically). I don't know where to go from here.
I am at a loss.
Lets review.
1. New (rebuilt) Torque tube.
2. New TQ converter bearings (both of them)
3. Rebuilt Torque converter.
4. Rivets in rear flex plate tack welded into place.
5. Brand new Torque converter bolts.
I jacked the motor up off the shot engine mounts to make sure that was not creating a rattling noise. No improvement. The only things left are a section called "B-3" inside the transmission that I found mention of in the shop manuals (Transmission volume II in section 38 if I recall) regarding a rattling noise at 1500rpm, or, possibly a defective rebuilt torque tube. Mine rattles at idle in park or nuetral mostly, but will rattle in gear if I hit a certain RPM when decelerating (any time the drivetrain is not under load basically). I don't know where to go from here.
I am at a loss.
Last edited by killav; 09-05-2006 at 02:19 AM.
09-05-2006, 10:05 AM
#23
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
Mike,
That really sucks!!!
You are welcome to try one of my auto boxs to isolate the problem to the gearbox - a lot of work though.
Tack welding the flex plate bolts took care of one area we were concerned about.
Hopefully someone else will have some better ideas.
Roger
That really sucks!!!
You are welcome to try one of my auto boxs to isolate the problem to the gearbox - a lot of work though.
Tack welding the flex plate bolts took care of one area we were concerned about.
Hopefully someone else will have some better ideas.
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."
09-05-2006, 11:15 AM
#24
Rennlist Member
Thread Starter
I didn't get any sleep last night. My mind is spinning. I've even thought about making some kind of mutant drive shaft that sits inside the structural Torque Tube. With U-joints or something. But with virtually no angle on the u-joints, they would soon fail. They need some angle in order to squish the grease around inside the bearing cups.
The good thing is that I only put together what I needed to in order to test for the rattle. I did not install the suspension, brakes, e-cable, ect. So, in about an hour or two I can have it all apart again. At this point, I think I am going to pull the tube and ship it off for 928 intl. to make sure it's o.k. Jim had mentioned that some years came with three bearings inside the tube, while others came with only two. I would put a dozen bearings in there at this point if it would stop this rattle.
Another thought. Due to time constraints, we did not replace the rear main seal while up at Roger's house. There are some big hex or torx head bolts up behind the triangular flex plate at the front of the car. These bolt the part of the flywheel with teeth on it to the crank. Could these be slightly loose, causing a rattle?
The good thing is that I only put together what I needed to in order to test for the rattle. I did not install the suspension, brakes, e-cable, ect. So, in about an hour or two I can have it all apart again. At this point, I think I am going to pull the tube and ship it off for 928 intl. to make sure it's o.k. Jim had mentioned that some years came with three bearings inside the tube, while others came with only two. I would put a dozen bearings in there at this point if it would stop this rattle.
Another thought. Due to time constraints, we did not replace the rear main seal while up at Roger's house. There are some big hex or torx head bolts up behind the triangular flex plate at the front of the car. These bolt the part of the flywheel with teeth on it to the crank. Could these be slightly loose, causing a rattle?
09-05-2006, 02:13 PM
#25
Road Warrior
Rennlist Member
Rennlist Member
can you fire it up w/out the TT or trans connected?? might help isolate things by elimination.... sure it's not a bad cat or exhaust issue??? many noises can be transient - seem to come from anyplace but the source...
09-05-2006, 03:03 PM
#26
Chronic Tool Dropper
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Stethoscope....
09-05-2006, 03:27 PM
#27
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
Bob,
We used the stethoscope - first thing we did when we originally replaced the TT. The noise came from the Torque Converter at that time - hence the TC rebulid.
I'm stumped!
Roger
We used the stethoscope - first thing we did when we originally replaced the TT. The noise came from the Torque Converter at that time - hence the TC rebulid.
I'm stumped!
Roger
09-05-2006, 03:35 PM
#28
Rennlist Member
Thread Starter
928SS, Bob,
Good points. I did fire up the car without the trans connected. I bolted up the Torque converter housing so that I could listen to everything from this component back towards the engine. I wanted to also listen to my new bearings in the housing. Guess what, no noise. I am guessing that without the inertia of the torque converter, there is no noise. Right now, I have the exhaust completely un-bolted. Exhaust manifolds only. So I know the cat is not making the noise. I know your asking yourself how I can still hear the rattle. I can't while the car is running, but on shut-down, the noise is very prevalent. When the very loud exhaust shuts down, you can hear the distinct rattle as the TT spins to a stop. This all sounds like loose pinch bolts, Converter bearings or rivets but all of these items have been addressed.
Bob, I did try a piece of tubing to try and locate the noise before disassembly, with the complete exhaust still bolted up. If you listened at the front, it sounded like its coming from the front, if you moved to the back, it sounded like it is was coming from the back. The noise just travels all the way up and down the tube. It did, to my ears anyway, sound more like it was in the back of the car v.s. the front. That's why I took a shot and had the Tq converter rebuilt.
928 Intl. has graciously agreed to send me a different tube in order to eliminate the possibility of a bum tube. It is in the mail today. So I will have it by Monday and be able to eliminate that as a possibility. Tom at 928 did say that every once in a while they will get one that looks fine after a re-build, but if the shaft inside is not true, it can oscillate causing a noise.
Good points. I did fire up the car without the trans connected. I bolted up the Torque converter housing so that I could listen to everything from this component back towards the engine. I wanted to also listen to my new bearings in the housing. Guess what, no noise. I am guessing that without the inertia of the torque converter, there is no noise. Right now, I have the exhaust completely un-bolted. Exhaust manifolds only. So I know the cat is not making the noise. I know your asking yourself how I can still hear the rattle. I can't while the car is running, but on shut-down, the noise is very prevalent. When the very loud exhaust shuts down, you can hear the distinct rattle as the TT spins to a stop. This all sounds like loose pinch bolts, Converter bearings or rivets but all of these items have been addressed.
Bob, I did try a piece of tubing to try and locate the noise before disassembly, with the complete exhaust still bolted up. If you listened at the front, it sounded like its coming from the front, if you moved to the back, it sounded like it is was coming from the back. The noise just travels all the way up and down the tube. It did, to my ears anyway, sound more like it was in the back of the car v.s. the front. That's why I took a shot and had the Tq converter rebuilt.
928 Intl. has graciously agreed to send me a different tube in order to eliminate the possibility of a bum tube. It is in the mail today. So I will have it by Monday and be able to eliminate that as a possibility. Tom at 928 did say that every once in a while they will get one that looks fine after a re-build, but if the shaft inside is not true, it can oscillate causing a noise.
09-05-2006, 04:36 PM
#30
Rennlist Member
Thread Starter
I can't turn the wheels right now because they are on Ramps. All other symptoms are as follows.
1. Rattles only in park or nuetral. Usually does not rattle once put in gear. I've never heard it rattle with the motor off, unless you count when it is spinning to a stop after shut down.
2. Really noticable upon engine shut down. Even if in gear, as soon as the motor is killed, it rattles to a stop.
3. Transmission shifts perfectly. No weird behavior as far as I can tell.
4. The rattle has no pattern when the motor is running. Just sounds like loose nut's and bolts rattling around inside the TT. Kind of fades in and out.
My dad's advice is to put it together and drive it till it something breaks and then fix it. But I don't want my trans to grenade and ruin my rebuilt Tq Converter if that is the problem. And I don't think he understands the gravity of pulling a torque tube, suspension, and trans. two or three times.
1. Rattles only in park or nuetral. Usually does not rattle once put in gear. I've never heard it rattle with the motor off, unless you count when it is spinning to a stop after shut down.
2. Really noticable upon engine shut down. Even if in gear, as soon as the motor is killed, it rattles to a stop.
3. Transmission shifts perfectly. No weird behavior as far as I can tell.
4. The rattle has no pattern when the motor is running. Just sounds like loose nut's and bolts rattling around inside the TT. Kind of fades in and out.
My dad's advice is to put it together and drive it till it something breaks and then fix it. But I don't want my trans to grenade and ruin my rebuilt Tq Converter if that is the problem. And I don't think he understands the gravity of pulling a torque tube, suspension, and trans. two or three times.