LWFW, First Impressions
09-19-2006, 03:01 PM
#16
Burning Brakes
Cool. Well, good luck with all that! and thanks for clearing that up! I was thinking there might be a way to RR the clutch for "free". But I guess I need another problem first...hah.
09-19-2006, 06:44 PM
#17
Instructor
Join Date: Oct 2003
Location: Santa Fe, New Mexico
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Ray, I agree with your commennts regarding first-hand experience about the RS mounts. But, keep in mind they are somewhat firmer than the stock, but not over the top as with the Cup mounts for street/track.
I suspect the RS mounts will be an improvement..., in keeping with the overall balance of performance of the GT3. The only other addition I plan will be Euro Pipes. Aside from Sunset, Suncoast Porsche, also has competitive pricing, especially on Euro parts for GT3's.
Jack
I suspect the RS mounts will be an improvement..., in keeping with the overall balance of performance of the GT3. The only other addition I plan will be Euro Pipes. Aside from Sunset, Suncoast Porsche, also has competitive pricing, especially on Euro parts for GT3's.
Jack
09-19-2006, 07:00 PM
#18
Originally Posted by RayGT3
It was a noise that's comming from that area and the clutch kit was installed to remedy, to no avail. I'm thinking it's the thrust bearing . But before they change the motor they have to exaust any other possibilities. If they change the motor and Porsche finds no problems the dealership gets saddled with a bill for $20k. So they're making real sure that it's not something else other than the bearing. At this point I think we're real close to going with a new motor. But in the mean time I'm getting loads of new parts.
09-19-2006, 07:18 PM
#19
Burning Brakes
Thread Starter
Carrera GT,
The noise is reminesent of a bad bearing, metal on metal screching sound. Started softly and getting louder over time. It's hard to point to its exact location, but our best guess is the rear of the motor just before the RMS. We have tried several types of RMS with no affect on the noise.
Origonally were considering a possible bad throw out bearing or clutch hardware but they changed everything with no change in the noise. Really doesn't sound like a tranny noise, comming from further tward the engine.
I spoke to some racing buddies out in Ca., early on, and they suggested the thrust bearing, as they have had problems with these before. As it turns out they may have been correct. Although we did check the crank end play and seemed within specs. but the bearing could still be bad and the end play be ok.
The big problem is if they change the motor and AG doesn't find anythig wrong the dealership will get stuck for a $20K bill. So they're being very careful to follow Porsche's directions to the letter to avoid liability. But I think we're comming to the end of the road and a motor change is inevatable. We've changed everything that it could be at least once, sometimes 3 times.
The noise is reminesent of a bad bearing, metal on metal screching sound. Started softly and getting louder over time. It's hard to point to its exact location, but our best guess is the rear of the motor just before the RMS. We have tried several types of RMS with no affect on the noise.
Origonally were considering a possible bad throw out bearing or clutch hardware but they changed everything with no change in the noise. Really doesn't sound like a tranny noise, comming from further tward the engine.
I spoke to some racing buddies out in Ca., early on, and they suggested the thrust bearing, as they have had problems with these before. As it turns out they may have been correct. Although we did check the crank end play and seemed within specs. but the bearing could still be bad and the end play be ok.
The big problem is if they change the motor and AG doesn't find anythig wrong the dealership will get stuck for a $20K bill. So they're being very careful to follow Porsche's directions to the letter to avoid liability. But I think we're comming to the end of the road and a motor change is inevatable. We've changed everything that it could be at least once, sometimes 3 times.
09-20-2006, 01:47 AM
#20
Diagnosing noises is always interesting. I haven't heard of any consistent failures in the GT3 engine, so I'm curious to see how this unfolds. Do you know the diagnostic sequence Porsche has recommended for the dealer to follow?
I wonder if a pro engine builder or someone campaigning cup cars could go over it and recognise the culprit.
I wonder if a pro engine builder or someone campaigning cup cars could go over it and recognise the culprit.
09-20-2006, 03:22 AM
#21
Burning Brakes
Thread Starter
There had been some dicsussion of someone from AG Germany comming over to take a gander. Don't know where that stands, presently. Being in Buffalo the local cup car personell is somewhat limited. Joe Sahlen and Joel Rieser live in the area. I thought of giving them a call, but I have to be careful as to how much I get involved. I don't want to find myself with this being my problem. I don't mind making a suggestion or two but will leave getting personell in to diagnose problems up to the folks at Porsche.
As to the diagnostic method, its been try this and let us know what happens then try something else. Started with wheel bearings, now we're into engine bearings. I don't know of any definative way of telling if the thrust bearing is the culprit. I guess the only way is to illliminate everything else. Which it appears we are doing. It would be nice to know what the problem is, but at this point, considering the amount of time and money being spent, I wish someone would just make the decision to make the motor change and get it over with. Patience,............ patience.........
In regards to the thrust bearing, the potiental problem being, every time you start the car you have to press the clutch pedal to the floor. This puts all that pressure on the thrust bearing and to make matters worse, initally there is no oil pressure so the bearing is side loaded and pretty much dry for a short period of time. Not a good situation. This was brought up by some cup car guys when I was initially investagating this. When I described what was hapening they brought up this bearing right away, stating they have had similar problems as well.
I have been very fortunate in that the dealer has been very good to work with. In reality I feel all parties are doing everything possible to fix the problem. Suprisingly they even listen and try some suggestions made by me. It has been my experience that usually customer input is ignored. As I'm trying to tell them how to do their job. Greatfully this case is an exception. Again I can't praise Porsche enough for their diligance with this problem. You always hear the horror stories but rarely the good encounters.
As to the diagnostic method, its been try this and let us know what happens then try something else. Started with wheel bearings, now we're into engine bearings. I don't know of any definative way of telling if the thrust bearing is the culprit. I guess the only way is to illliminate everything else. Which it appears we are doing. It would be nice to know what the problem is, but at this point, considering the amount of time and money being spent, I wish someone would just make the decision to make the motor change and get it over with. Patience,............ patience.........
In regards to the thrust bearing, the potiental problem being, every time you start the car you have to press the clutch pedal to the floor. This puts all that pressure on the thrust bearing and to make matters worse, initally there is no oil pressure so the bearing is side loaded and pretty much dry for a short period of time. Not a good situation. This was brought up by some cup car guys when I was initially investagating this. When I described what was hapening they brought up this bearing right away, stating they have had similar problems as well.
I have been very fortunate in that the dealer has been very good to work with. In reality I feel all parties are doing everything possible to fix the problem. Suprisingly they even listen and try some suggestions made by me. It has been my experience that usually customer input is ignored. As I'm trying to tell them how to do their job. Greatfully this case is an exception. Again I can't praise Porsche enough for their diligance with this problem. You always hear the horror stories but rarely the good encounters.
09-20-2006, 11:39 AM
#22
This isn't sounding like a horror story just yet (wait until they drop in the engine and the noise is still there and now you have a car with a non-matching engine ... )
It is disconcerting to say the least that faced with a "noise" they don't have a plan and they're groping in the dark. This car has been in production for two or three years and the engine for over a decade in one form or another. Presumably they have isolated the noise to something consistent with an engine bearing. I guess the bearing could fail without sending metal into the oil. I guess. Have they cut open the filter to look for metal?
Anyway, I'm not sure how paying a local race team an hour or two to go over it will in any way put this problem in your lap. If this were a customer car and I was the bozo with the wrench, I'd be calling on the local engine builder experts for advice. And I'd have a documented process of elimination (to isolate the possible sources of the noise) and a diagnostic sequence to eliminate the basics (power steering, alternator, cooling) and making sure several pairs of ears went through and confirmed the noise was related to engine speed or load and the position of the gear selector and clutch pedal.
If I understand correctly, they've replaced the flywheel, pilot bearing and guide tube but not the pressure plate. And you chose a lightweight flywheel. They were in there to find the noise, so they would have noticed wear on the guide tube or anything wrong with the clutch disk or the pressure plate (hopefully.) I'm somewhat optimistic that the noise could still be outside the engine since I tend to consider that to be about the most reliable "component" in the whole car.
Well, I can't say I'm too impressed with the dealer or their techs but at least they're not saying "drive it till it breaks" and they're not pushing back and saying it's somehow your fault. After all, unless they have a code in the OBD to report driver error, it's in their court.
As for the clutch down starting, it's certainly not healthy for the gearbox to be asked to sit clutch-out for any longer than necessary and when I hear the complaint "noise" that's what I assume on a slow-n-go commuter with 50K+ miles.
By the way, I wouldn't rule out the LSD. : ) So I'm keen to hear what they've done to isolate the source of the noise and what the status of each of the related elements can be when the noise occurs.
I've played with a lot of '04 and '05 GT3's but only recently bought one for myself -- I do notice it has a lot more mechanical noise than any other street 911 I've known. And once you take out the rear carpet, it's quite a racket back there.
It is disconcerting to say the least that faced with a "noise" they don't have a plan and they're groping in the dark. This car has been in production for two or three years and the engine for over a decade in one form or another. Presumably they have isolated the noise to something consistent with an engine bearing. I guess the bearing could fail without sending metal into the oil. I guess. Have they cut open the filter to look for metal?
Anyway, I'm not sure how paying a local race team an hour or two to go over it will in any way put this problem in your lap. If this were a customer car and I was the bozo with the wrench, I'd be calling on the local engine builder experts for advice. And I'd have a documented process of elimination (to isolate the possible sources of the noise) and a diagnostic sequence to eliminate the basics (power steering, alternator, cooling) and making sure several pairs of ears went through and confirmed the noise was related to engine speed or load and the position of the gear selector and clutch pedal.
If I understand correctly, they've replaced the flywheel, pilot bearing and guide tube but not the pressure plate. And you chose a lightweight flywheel. They were in there to find the noise, so they would have noticed wear on the guide tube or anything wrong with the clutch disk or the pressure plate (hopefully.) I'm somewhat optimistic that the noise could still be outside the engine since I tend to consider that to be about the most reliable "component" in the whole car.
Well, I can't say I'm too impressed with the dealer or their techs but at least they're not saying "drive it till it breaks" and they're not pushing back and saying it's somehow your fault. After all, unless they have a code in the OBD to report driver error, it's in their court.
As for the clutch down starting, it's certainly not healthy for the gearbox to be asked to sit clutch-out for any longer than necessary and when I hear the complaint "noise" that's what I assume on a slow-n-go commuter with 50K+ miles.
By the way, I wouldn't rule out the LSD. : ) So I'm keen to hear what they've done to isolate the source of the noise and what the status of each of the related elements can be when the noise occurs.
I've played with a lot of '04 and '05 GT3's but only recently bought one for myself -- I do notice it has a lot more mechanical noise than any other street 911 I've known. And once you take out the rear carpet, it's quite a racket back there.
09-20-2006, 01:15 PM
#23
Burning Brakes
Thread Starter
The noise is the same, clutch in, clutch out, in gear, out of gear or any combination there of. Standing still, driving, same noise. Pretty much rules out everything from the flywheel back. Only thing necessary to make the noise is have the engine running and above 1200 rpm with very little load. Can't even get the sound to change pitch, always the same only getting louder over time. I really think it's the thrust bearing. But I've been wrong before.
09-20-2006, 03:17 PM
#24
Originally Posted by RayGT3
The noise is the same, clutch in, clutch out, in gear, out of gear or any combination there of. Standing still, driving, same noise. Pretty much rules out everything from the flywheel back. Only thing necessary to make the noise is have the engine running and above 1200 rpm with very little load. Can't even get the sound to change pitch, always the same only getting louder over time. I really think it's the thrust bearing. But I've been wrong before.
09-20-2006, 03:42 PM
#25
Three Wheelin'
Originally Posted by Carrera GT
Okay, well, that was pretty much the situation you described. Given the elimination of everything except the pressure plate from the transaxle, that's where I'd go first. But I'd also get it on a rolling road (or a full dyno) or just roll around somewhere secluded and use a stethoscope to try to isolate the origin of the noise (if not the source.) Fingers crossed, it's the pressure plate, otherwise, please take plenty of photos when the tech from Porsche AG shows up and when the new motor shows up in a crate and the swap itself etc. etc. ... oh and the look on their faces if the noise is still there ... : ))
can you fit my car into your schedule and service it next?
needs a new pcm.
btw you buying my car or getting a c4s?
jeff
09-20-2006, 05:01 PM
#26
Originally Posted by icon
cgt,
can you fit my car into your schedule and service it next?
needs a new pcm.
btw you buying my car or getting a c4s?
jeff
can you fit my car into your schedule and service it next?
needs a new pcm.
btw you buying my car or getting a c4s?
jeff
And service, sure, as long as you don't mind having it in bits for a year or two while I fiddle around with upgrades and whatever occurs to me along the way.
But I do like this idea of there being a perfectly good GT3 engine about to come out of RayGT3's car ... sounds like it would be nice to drop that into a Cayman ... a quick bit of bearing work, take it out to 4.0 litres "while your in there" and you've got a giant-killer sleeper par excellence. Oh the stuff of dreams!
