Re: Grant's project - "keeping us all informed" |  |  |
|
Buying through this link, gets PB a donation. |
Products for your Boxster, Cayman and Carrera. |
 | |
| Grant's project - "keeping us all informed" grant - Friday, 4 January, 2013, at 7:51:36 pm |
.. as was requested.....
I inspected the old motor today. note - this is after 150k miles - the original died due to IMS failure at 47k, replaced by a Porsche crate motor.
On bank A, the cams were in alignment with each other, and appeared to be in alignment with the crank. The locking tool could be installed.
On Bank B, the cams were out of alignment with the crank, and the tool could nto be installed. So one bank jumped time and the other didn't.
See the two cams? Notice that the one with the locking channel is not aligned with the other cam? That's not good.....
[i47.tinypic.com]
I pulled the IMS. Intact. In fact, fairly tight. I did not take it apart, but it spun, had some tension, and very little wobble. Single row. Came out easily.
Here it is:
[i50.tinypic.com]
Still in its cozy den:
[i45.tinypic.com]
So what's the bottom line? No IMS failure here. Likely a chain shoe or similar on bank B. Who knows why, but they are another known wear item and point of failure - just too hard to replace ( as opposed to the pre-2005 IMS bearings which pop out from the outside)
Mostly some data points FYI.
Grant
Grant
gee-lenahan-at-gee-mail-dot-com
Edited 1 time(s). Last edit at 01/04/2013 07:53PM by grant. (view changes)
I inspected the old motor today. note - this is after 150k miles - the original died due to IMS failure at 47k, replaced by a Porsche crate motor.
On bank A, the cams were in alignment with each other, and appeared to be in alignment with the crank. The locking tool could be installed.
On Bank B, the cams were out of alignment with the crank, and the tool could nto be installed. So one bank jumped time and the other didn't.
See the two cams? Notice that the one with the locking channel is not aligned with the other cam? That's not good.....
[i47.tinypic.com]
I pulled the IMS. Intact. In fact, fairly tight. I did not take it apart, but it spun, had some tension, and very little wobble. Single row. Came out easily.
Here it is:
[i50.tinypic.com]
Still in its cozy den:
[i45.tinypic.com]
So what's the bottom line? No IMS failure here. Likely a chain shoe or similar on bank B. Who knows why, but they are another known wear item and point of failure - just too hard to replace ( as opposed to the pre-2005 IMS bearings which pop out from the outside)
Mostly some data points FYI.
Grant
Grant
gee-lenahan-at-gee-mail-dot-com
Edited 1 time(s). Last edit at 01/04/2013 07:53PM by grant. (view changes)
| Re: Grant's project - "keeping us all informed" dghii - Friday, 4 January, 2013, at 10:25:30 pm |
Great pics...I'm sorry for your bad luck.
Perhaps a relief to know that its nothing that you did, or could have done to prevent the failure. You got good mileage out of the motor but, unfortunately nothing great compared to most modern cars. Too bad given the car and feeding you gave the car over the years.
I will not consider replacing the bearing in my 2000S with 106K miles until the car needs a clutch (no time soon it seems). If the IMS fails before the clutch, I will not have any regrets. I'll just have to decide weather to replace the motor or the car.
I will be disappointed if the motor doesn't last as long as my 84 Alfa Spider....that WOULD be embarrassing (for Porsche)!
dghii
2000 Boxster S 6speed 112k miles
Perhaps a relief to know that its nothing that you did, or could have done to prevent the failure. You got good mileage out of the motor but, unfortunately nothing great compared to most modern cars. Too bad given the car and feeding you gave the car over the years.
I will not consider replacing the bearing in my 2000S with 106K miles until the car needs a clutch (no time soon it seems). If the IMS fails before the clutch, I will not have any regrets. I'll just have to decide weather to replace the motor or the car.
I will be disappointed if the motor doesn't last as long as my 84 Alfa Spider....that WOULD be embarrassing (for Porsche)!
dghii
2000 Boxster S 6speed 112k miles
| Other than tha IMS bearing .. Pedro (Odessa, FL) - Saturday, 5 January, 2013, at 7:57:30 am |
... the most common failure for cars that are tracked are lubrication issues generally in cylinder 6.
Lubrication issues ca encompass broken rods, worn bushings, slipped sleeves, etc.
You may be able to find some signs of overheating.
It happens most on cylinder 6 because it's the farthest one down the oiling line.
Don't just say: "it jumped time so the engine died". Try to find out what failed first which made it jump time.
It's a good exhercise where one can learn a lot from.
Happy Boxstering
Pedro
Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)
Racecar spelled backwards is Racecar
"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"
"If you wait, all that happens is that you get older"... Mario Andretti
"Being second is to be the first of the ones who lose" ... Ayrton Senna
Lubrication issues ca encompass broken rods, worn bushings, slipped sleeves, etc.
You may be able to find some signs of overheating.
It happens most on cylinder 6 because it's the farthest one down the oiling line.
Don't just say: "it jumped time so the engine died". Try to find out what failed first which made it jump time.
It's a good exhercise where one can learn a lot from.
Happy Boxstering
Pedro
Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)
Racecar spelled backwards is Racecar
"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"
"If you wait, all that happens is that you get older"... Mario Andretti
"Being second is to be the first of the ones who lose" ... Ayrton Senna
| Good points... but I never tracked that engine. I did my first, but not this one. *NM* Bruce In Philly (2000 S Boxster, now '09 C2S) - Saturday, 5 January, 2013, at 8:20:32 am |
| Juts for clarity to all... this was not my car.... it was Bruce's grant - Saturday, 5 January, 2013, at 9:03:38 am |
not tracked much (non on this motor)
never on slicks
Just driving down the highway - he told the long story many moons ago here.
Everyone, including his wrench, assumed it was an IMS failure. But apparently not.
I'm not taking it apart any further since i hope to sell the core, and was advised that they might not want a bucket of stuff taken apart by an unknown entity.....
Grant
Grant
gee-lenahan-at-gee-mail-dot-com
never on slicks
Just driving down the highway - he told the long story many moons ago here.
Everyone, including his wrench, assumed it was an IMS failure. But apparently not.
I'm not taking it apart any further since i hope to sell the core, and was advised that they might not want a bucket of stuff taken apart by an unknown entity.....
Grant
Grant
gee-lenahan-at-gee-mail-dot-com
| Interesting information Guenter in Ontario - Saturday, 5 January, 2013, at 10:45:22 am |
MikenOH - Saturday, 5 January, 2013, at 12:02:55 pm |
To find out if it was an IMS failure, an owner would have to spend some $'s on the tear-down to do the evaluation.
I'm not sure how many owners would want to spend good $ money on the post-mortem that would otherwise be spent on a new motor or new ride.
Very interesting Grant--please keep sending us the reports on your progress.
I'm not sure how many owners would want to spend good $ money on the post-mortem that would otherwise be spent on a new motor or new ride.
Very interesting Grant--please keep sending us the reports on your progress.
| Some thoughts on IMS bashing....... Bruce In Philly (2000 S Boxster, now '09 C2S) - Saturday, 5 January, 2013, at 10:20:53 pm |
Hmmm..... makes you wonder eh? As Grant noted, even my Porsche mechanic thought it was the IMS..... he has seen many many of these fail. As Guenter noted "Make you wonder how many other "IMS failures" weren't really IMS but something else"..... Hmmmm..
I don't know what to make of all of this.... in short, none of us have the real data... only Porsche really knows. As most know here, this was my second engine failure. You may want to blame me, but what I can say in my defense is that I really babied this thing when it came to maintenance. I followed the book to the letter and never let a creak or rattle rest.... I fixed it as my strategy was to keep the car for as long as I could. I was still on the original clutch! 197K miles on that clutch!
After thinking about this for a while, I gotta say, Porsche had a problem of an engine and I am amazed there are no real class action suites against them. I heard saber rattling before, but they really had a lemon of an engine design here. Sorry, I know that is not what folks want to hear, but....... Grant, maybe you want to use Jake Raby's updates to the new engine? He knows the failure modes well...... but again, the truth is a little foggy without the real data... and Porsche likes it that way.
Bruce..... :-(
I don't know what to make of all of this.... in short, none of us have the real data... only Porsche really knows. As most know here, this was my second engine failure. You may want to blame me, but what I can say in my defense is that I really babied this thing when it came to maintenance. I followed the book to the letter and never let a creak or rattle rest.... I fixed it as my strategy was to keep the car for as long as I could. I was still on the original clutch! 197K miles on that clutch!
After thinking about this for a while, I gotta say, Porsche had a problem of an engine and I am amazed there are no real class action suites against them. I heard saber rattling before, but they really had a lemon of an engine design here. Sorry, I know that is not what folks want to hear, but....... Grant, maybe you want to use Jake Raby's updates to the new engine? He knows the failure modes well...... but again, the truth is a little foggy without the real data... and Porsche likes it that way.
Bruce..... :-(
Gary in SoFL - Sunday, 6 January, 2013, at 7:10:49 am |
Quote
Bruce In Philly (2000S Morte)
Hmmm..... makes you wonder eh? .....Grant, maybe you want to use Jake Raby's updates to the new engine? He knows the failure modes well...... but again, the truth is a little foggy without the real data... and Porsche likes it that way.
Very unfortunate about your issues, Bruce, and yes, many of us wonder about the probable over reporting of IMS failures just because it's an easy or self serving label. Whatever the cause, the M96 is a suspect engine.
I'm sure I don't need to point out it isn't only Porsche who likes to keep things foggy.
"A mile of highway will take you one mile. A mile of runway will take you anywhere."
| I still loved the car....... Bruce In Philly (2000 S Boxster, now '09 C2S) - Sunday, 6 January, 2013, at 9:19:01 am |
I am glad Grant is bringing it back to life. I would have but I was between incomes and wanted to constrain my spend for a while. I came within a fraction of a second from pulling the trigger on a new engine from Jake Raby. He was very backed up and would not have the car ready by late March... at best. I spoke with him and did some research..... spoke on the phone with a few other folks who owned or installed his engines and the reviews were stellar. For about the same price as a replacement crate engine from Porsche, I would get my engine rebuilt, bored out a bit, and all failure modes addressed. I forget the details but it was about 300HP .... . about 20 grand ... he uses the stock exhaust for, get this, performance reasons. Now that would be a fun car.
I had replaced virtually all the suspension parts.... other stuff maintained/replaced... When I discussed a Raby engine replacement with my mechanic, he soberly told me I could buy two Boxsters like mine for that price..... Hmmmm....... I didn't think that was quite a equal comparison as my car was meticulously maintained and in darn good shape.... I dunno.... interesting decision set.
So, now that I am back in "income land", I am looking for an '09 911. If the timing of my failure was different, I am pretty darn shure I would have put a Raby engine in to the thing. 50 more HP and all common failure modes address?... Great reviews from people who had hands on experience with his engines.... hmmmm.....
Bruce in Philly
I had replaced virtually all the suspension parts.... other stuff maintained/replaced... When I discussed a Raby engine replacement with my mechanic, he soberly told me I could buy two Boxsters like mine for that price..... Hmmmm....... I didn't think that was quite a equal comparison as my car was meticulously maintained and in darn good shape.... I dunno.... interesting decision set.
So, now that I am back in "income land", I am looking for an '09 911. If the timing of my failure was different, I am pretty darn shure I would have put a Raby engine in to the thing. 50 more HP and all common failure modes address?... Great reviews from people who had hands on experience with his engines.... hmmmm.....
Bruce in Philly
| Modes of failure mikefocke, '01S Sanford, NC - Sunday, 6 January, 2013, at 11:23:53 am |
Jake says he has seen 24 modes of failure (any one of which could have been misdiagnosed as IMS given the lack of engine internals inspection that was going on). I've never seen a list posted.
For years Porsche said the only replacement/repair was to send the unopened engine back to them for a swap. No wonder there was not much knowledge build up in the repair community.
For years Porsche said the only replacement/repair was to send the unopened engine back to them for a swap. No wonder there was not much knowledge build up in the repair community.
| Odd..... Bruce In Philly (2000 S Boxster, now '09 C2S) - Sunday, 6 January, 2013, at 12:04:50 pm |
With all of the old American iron around when I was younger, I never heard of any total engine failures other than those caused by total loss of oil or from engine performance mods. Our cars rotted out, fell apart, pieces like pumps constantly failed, chassis shook, etc... but I never remember engines mysteriously blowing up. I guess we gained on some and lost on others as time moved on and engineering became more sophisticated.
Bruce in Philly
Bruce in Philly
| Not so odd really... grant - Sunday, 6 January, 2013, at 5:01:07 pm |
... a modern porsche motor is designed to be very light and have a very high specific output. This means it must be stressed much higher in both output/L and in terms of RPMs. Not only is it stressed more, but to achieve this they must use more complex valvetrains - and that's where most of the problems lie. Look at all the chains, vario-cams, end bearings, guides, shows, tensioners etc - all operating at up to 7k rpms. Lose a tensioner, a cam alignment hydraulic doo-hickey etc and things snowball, and not in a good way.
Compare that to an iron block, with half the output/L; a single cam in block, 4500-5k effective redline, solid lifters, and pushrods.
Finally, the were all rebuilt by 100k due to worn cams, rings and cylinders. OTOH, your 3.2 M96 motor went 150k miles with full performance until ti went "boom". I bet very few 426s did that.
That said, i had friends who in the day spewed the guts of their hemis and GTOs when timing failed. But i agree, it was fewer.
As we push for the highest power and the lowest weight, that agricultural durability is compromised. Extended drain intervals dont help much either.
So there are two sides to the story, or at least I think so.
Grant
Grant
gee-lenahan-at-gee-mail-dot-com
Compare that to an iron block, with half the output/L; a single cam in block, 4500-5k effective redline, solid lifters, and pushrods.
Finally, the were all rebuilt by 100k due to worn cams, rings and cylinders. OTOH, your 3.2 M96 motor went 150k miles with full performance until ti went "boom". I bet very few 426s did that.
That said, i had friends who in the day spewed the guts of their hemis and GTOs when timing failed. But i agree, it was fewer.
As we push for the highest power and the lowest weight, that agricultural durability is compromised. Extended drain intervals dont help much either.
So there are two sides to the story, or at least I think so.
Grant
Grant
gee-lenahan-at-gee-mail-dot-com
Laz - Sunday, 6 January, 2013, at 8:29:37 pm |
| Boy I sure blew a lot of '60s engines mikefocke, '01S Sanford, NC - Monday, 7 January, 2013, at 2:44:35 pm |
So the point is, don;t loan Mike your car?  grant - Monday, 7 January, 2013, at 6:59:37 pm |
| Don't be old enough to remember how truely poor the old ones really were! *NM* mikefocke, '01S Sanford, NC - Tuesday, 8 January, 2013, at 4:30:45 pm |
| Re: Not so odd really... San Rensho - Monday, 7 January, 2013, at 7:39:10 pm |
Quote
grant
... a modern porsche motor is designed to be very light and have a very high specific output. This means it must be stressed much higher in both output/L and in terms of RPMs. Not only is it stressed more, but to achieve this they must use more complex valvetrains - and that's where most of the problems lie. Look at all the chains, vario-cams, end bearings, guides, shows, tensioners etc - all operating at up to 7k rpms. Lose a tensioner, a cam alignment hydraulic doo-hickey etc and things snowball, and not in a good way.
Compare that to an iron block, with half the output/L; a single cam in block, 4500-5k effective redline, solid lifters, and pushrods.
Finally, the were all rebuilt by 100k due to worn cams, rings and cylinders. OTOH, your 3.2 M96 motor went 150k miles with full performance until ti went "boom". I bet very few 426s did that.
That said, i had friends who in the day spewed the guts of their hemis and GTOs when timing failed. But i agree, it was fewer.
As we push for the highest power and the lowest weight, that agricultural durability is compromised. Extended drain intervals dont help much either.
So there are two sides to the story, or at least I think so.
You are right, these engines are engineered to run on the hairy edge, but what causes catastrohic engine failure? It's not the state
of the art inovations, like complicated valve train management or the high tech cylinder coating systems, it's really simple stuff, an IMSB, that costs a couple of bucks,that fails, chain tensopner pads that fail, simple oiling problems. It's simple systems that cause most of the problems and that is Porsches failure.
Grant
| Re: Grant's project - "keeping us all informed" Alcantera - Sunday, 6 January, 2013, at 9:35:28 am |
The re builders we use told me he has taken apart more than a few core engines and found nothing wrong. He said that they were probably misdiagnosed AOS failures. Ouch! This has died down in the last few years as more guys are aware of the AOS problem. Makes you wonder what happened to the car with the replacement engine.. Another little scam is calling the insurance company and reporting that I ran over metal on the highway and it punched a hole in my engine!!! I guess these guys are not worried that the only insurance adjuster is going to crawl under the car to see which way the aluminum around the hole is facing in or out. My favorite is " someone put something in my gas tank and my motor blew " I guess the adjuster never checked to see if you can open the gas tank flap with the car locked.
Sorry, only registered users may post in this forum.