“IMS” failure prevention
03-25-2011, 11:06 PM
#16
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Join Date: Mar 2011
Location: Plano Texas
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There was a post a few weeks ago, I think it was on the 987 forum, about a study that linked IMS failure to cars that were driven far too softly; seems that high rpms are require to properly lubricate the bearing. Cars that were tracked, or regularly "drove it like you stole it" rarely suffer IMS problems, whereas garage queens and babied cars suffered much higher rates.
Might as well err on the side of caution
Edit: https://rennlist.com/forums/987-foru...che-email.html
Might as well err on the side of caution
Edit: https://rennlist.com/forums/987-foru...che-email.html
03-26-2011, 06:30 AM
#17
Instructor
Thread Starter
Porsches are made to be driven
Porsches are made to be driven.
Drive it everywhere, all of the time, just do not lug the engine. Somebody recommended 2,500 rpm minimum but I find it hard to not drop down to 2,000 rpm sometimes. I like the instant throttle response between 3,000 and 5,000 rpm with the increased torque.
The Boxster inherits its twin-resonance air induction system from the 911 Carrera. The system acts as a “resonance supercharger,” allowing the engine to draw from higher velocity airflow at certain engine speeds. A crossover pipe connects the individual air collector/resonance chambers for each cylinder bank. A flap in the pipe remains closed from idle to about 3,100 rpm. When it opens, each cylinder bank can draw from airflow “excited” by the resonance created by alternating induction between all six cylinders. In essence, “dual resonance” creates two induction paths for each cylinder. Below 3,000 rpm, the cylinders draw air from a “short” path.
From 3,000 rpm to about 5,100 rpm – when the resonance flap opens – the cylinders draw from a long intake path, which boosts torque. Above 5,100 rpm, the flap again closes to allow the cylinders to draw intake air from a shorter intake path to boost horsepower.
From 3,000 rpm to about 5,100 rpm – when the resonance flap opens – the cylinders draw from a long intake path, which boosts torque. Above 5,100 rpm, the flap again closes to allow the cylinders to draw intake air from a shorter intake path to boost horsepower.
03-28-2011, 06:42 PM
#18
Burning Brakes
The optimum is to drive it for at least as long as it takes to get the fluids warmed up every time you start it up. I hear of more problems with cars that have been on used car lots for months or are just being taken out of winter hibernation than I do of cars driven daily. When I worked, I absolutely drove the car every day the road temps would allow me to drive it given that I only had summer tires. Even today, the CRV gets the 1 mile trips, the Boxster gets the dozen mile ones.
Last edited by mikefocke; 03-29-2011 at 04:56 PM.
03-31-2011, 01:01 PM
#19
Advanced
Well let me say that I just bought my first Boxster. Its a 05 S. I got the extended warranty when I bought it because I didn't want to drive out and have a problem within the first month or so. But now I hear about IMS failure and I'm thinking I should get rid of this stinking warranty that I only bought because its a Porshe, and get that upgrade.
04-14-2011, 11:35 PM
#21
Intermediate
Just completed the swap here are some pictures:
Engine Pre-swap.
The New new LN bearing in place.
Old bearing out of the car.
This bearing had over 114k on it. When I pulled it it more or less seemed prefect, without any wobble or play. (Most of the miles on my car came from consistent highway driving, but of a few of the owners keep it as a garage too toy. Most recently I put 20k on it in about 6 months cruising down the freeway on my commute. It's somewhat annoying to have spent this much money on a seemly fine bearing but the piece of mind is certainly nice.
Engine Pre-swap.
The New new LN bearing in place.
Old bearing out of the car.
This bearing had over 114k on it. When I pulled it it more or less seemed prefect, without any wobble or play. (Most of the miles on my car came from consistent highway driving, but of a few of the owners keep it as a garage too toy. Most recently I put 20k on it in about 6 months cruising down the freeway on my commute. It's somewhat annoying to have spent this much money on a seemly fine bearing but the piece of mind is certainly nice.
04-15-2011, 02:54 AM
#22
I bought an '02 986 S with 57k and had RUF do the IMS and clutch immediately.
Yeah, it cost a few bucks but it's good insurance.
Yeah, it cost a few bucks but it's good insurance.
07-11-2011, 06:10 PM
#23
Advanced
Has anybody got recommendations for an independant repair outfit that does ims replacement for my 2001 Boxster in Western Canada? I live in Edmonton. No problems yet but am looking at it as a preventative measure.
07-18-2011, 05:57 PM
#25
Burning Brakes
Prevention...good new oil all the time is your best defense but even that isn't a sure thing. There is an aftermarket pre-failure detection kit coming out from www.flat6innovations.com. Search the products section...
11-22-2011, 03:00 AM
#30
Instructor
Thread Starter
IMS: what we found inside
When the inner bearing seal deteriorates because of heat, the oil washes the permanent grease out of the bearings case. At low RPMs speed is not high enough to develop an elastohydrodynamic film to overcome surface irregularities. This metal-to-metal contact, leads to the failure of the IMS bearing and subsequently to a blown engine because the cam timing is off. Little is known about the history of my car, so after all the scare story’s floating around Boxster forums, during a recent clutch installation, on #620323 probably the 323 American Boxster, 68,000 miles. There is a shop here in Hawaii that replaced it as preventative maintenance with LNs lightweight ceramic hybrid bearing, made with tool steel races, and Timken sintered silicon nitride ultra-low friction roller *****. It took about two hours plus the clutch job. Combined with the lack of rear grease seals, the new bearing is lubricated by splash, as well as submersion lubrication. Ceramic is designed specifically for poor lubrication, and high heat.This is what we found already on my car.
The stock Emishaft intermediate shaft bearing cover, dual row bearing, with no outer seal.
You can see that there is no slot in the center stud, and there is no groove or marks on the outside.
The black bearing seal says Japan, IJK, 5204RS
It seems that one of the previous owners cared enough about the car to have already installed LN Engineerings Intermediate Shaft Bearing Retrofit Kit, and hidden it behind the original cover.
The stock Emishaft intermediate shaft bearing cover, dual row bearing, with no outer seal.
You can see that there is no slot in the center stud, and there is no groove or marks on the outside.
The black bearing seal says Japan, IJK, 5204RS
It seems that one of the previous owners cared enough about the car to have already installed LN Engineerings Intermediate Shaft Bearing Retrofit Kit, and hidden it behind the original cover.
