BruceP

No. Neither is American. It only becomes an insult when you attach pejorative adjectives to it, inferring that they're connected. For example, I'm actually a dual citizen, born in Illinois to Canadian parents. I might also be ugly. So, you can call me ugly, and that would be insulting but possibly true. You can call me American. That would be true. But calling me an ugly American would be bigoted.

Just wanted to clear that up.

Enjoy your fishing. Wear a life jacket.

PS Wait, you're a cyclist? That explains the attitude. We're all ******! Skiing in Banff the end of this month, actually. The last time I cycled there was a few years ago, on a relay team that was trying to set a record for Vancouver-to-Toronto. They were ******, too. The kind you drink iced vodka with, though.

Robin 993DX

Sorry to bring up an old argument. I am just beginning to study the IMS failures, but I am more interested in finding out more about the actual cause of the failue instead of identifying if Porsche makes ****ty cars.

So the failure of the IMS is from what?

Benjamin Choi

Robin, a good number of us here picked up Adrian Streather's excellent 996 book and on page 182, he submits some well researched, bulleted points about why IMS bearing failures cannot necessarily be pointed to manufacturing defect(s).

The speculative conclusion, if you will, to the IMS bearing failures is due to running the engine with low oil levels which is wholly the responsibility of the owner to keep full, and the type of oil which will certainly open up yet another can of oily worms in this forum.

Oh forty, based on my limited knowledge, does a better job than other oil weights in getting to all the nooks and crannies of the engine than the heavier oils that some of the others recommend here that are not recommend by Porsche. Porsche makes it VERY clear with their approved oil weight/brand list for all of their engines.

So pretty much, Streather's book recommends the obvious to us:

1) Maintain your oil level per the manual
2) Use Porsche approved oils

jsmirand

Adrian's book stating the IMS failure can't be pointed to a mfg defect may be true, but it can certaily be pointed to an engineering fault. The mfg may have been to spec, but if the engineering design is inherently weak, then failures will result.

My IMS failed with the oil topped off using Porsche approved oils.

Robin 993DX

So where were the engineering defect? Or what was the weakness of the design to cause it to fail?

Doug Donsbach

Robin, the July, 2006 article from the UK magazine Total 911 has a plausible description. To paraphrase their analysis of the problem, one of the sprockets on the intermediate shaft is retained with a small stud. The stud can break, destroying the bearing that supports the shaft. The unsupported shaft loses mesh with the chains driving the camshafts and mechanical chaos ensues.

Although the article isn't entirely clear, I believe they're talking about the rearmost sprocket on the intermediate shaft. That would be the sprocket on the right end of the shaft in the diagram below.

There is also at least one TSB related to changes in the sprocket and chains, but that TSB claims to change things to reduce noise.

Tippy

If anyone buys into this speculation.............wow...........I find this as crap.......sorry, I dont buy this speculation one bit................blaming the owners, spit spit

pete13

It seems like the failure was not anticipating people doing things advised against!!

And point of fact, obesity does impact more than half the population. Two thirds by most estimates. Same with heart disease (among the fifty plus at risk population).

Robin 993DX

Doug,

Thank you for the reply, I read that there were also update to bolt #15? When you said the right side sprocket, so looks in order to remendy this or to do any preventive work the engine have to come apart.

Doug Donsbach

The update to bolt #15 (3 each) was part of a TSB dealing with RMS replacement. That TSB also specified new bolts (4 each) to replace the bolts holding the rear of the crankcase together. The replacement bolts had sealant pre-applied to their threads and the surface under the head to stop oil wicking up the threads and causing an oil leak that would subsequently be misidentified as an RMS leak.

On Edit: Yeah, I don't think there is anything to "fix" there without disassembly of the engine.

BruceP

Anybody hazard a guess as to what the net dollar saving would be by doing this work versus waiting until it grenades and then replacing the motor?

chsu74

Good Idea! Instead of paying for the aftermarket warranty; get the updated IMS part installed.

Mother

I had a discussion with a engine repair shop in CA and he hardly saw any IMS problems, but the ones he did experience he noted that the IMS gear on the shafts where slipping causing the problem and he since modified it by pinning it of sorts in all his rebuilds.

Benjamin Choi

I'd lean on Adrian's experience and research along this front per what he has written on page 182 of his 996 book.

Rest easy, fellas. Just take care of that engine with some Porsche approved oils, keep an eye on topping it off as needed, and go enjoy the drive!

errico

when i bought the car they changed the ims gasket or seal, is this a good thing for me ? this crap is freaking me out.

either this car has no problems or you need a brand new engine.

lets pray.