IMS replacement, 997 or 996 with LN bearing

My 2005 996 suffered a IMS bearing failure. First thought was to replace the bearing with a LNE kit, but on disassembly of the engine it seams that the shaft itself is not serviceable. As I already purchased the LNE kit, I am now left with two options: 1. buy a good 2nd hand 996 IMS and use the LNE kit to replace the bearing 2. buy a complete new IMS, which is now the 997 part number with the larger bearing from factory. What is preferable from longevity standpoint?

I would go with option 1 since you can replace the IMS bearing again later as a maintenance item like so many others do. It is my understanding that if you choose option 2, you can never replace the bearings again without engine disassembly.

Are you doing the teardown? LN states that the LN bearing is not for a car that has had an IMS failure. Does the engine have other collateral damage? Did you shut it off right away? Too many questions left unanswered to advise.

So your splitting the case yourself? Do post pics you animal. Being as you only post once every two years could you do it before I expire?

:-) I drove the car 50 miles to work, parked it there and found a pool of oil on return. So the engine ran with a broken IMS bearing for anywhere up to 50 miles. It is probably my punishment for grinning about the krazyk IMS thread. Doing the work myself as the local porsche specialist is backlogged and as I do enjoy wrenching. Just did a total overhaul and calibration of the mfi pump on my 1973 911, so not a total novice. The motor is completely disassembled now. There is actually very little collateral damage apart from the IMS itself. The only other broken item was the chain tensioner paddle (not sure if that was cause or effect). The engine was torn down to assure that debris from IMS and bearing could be cleaned up. Now debating "while in there" upgrades. I would hate to put it back together again and have the d-chunk a few months down the road, so looking at hartech for new liners. btw, I believe that LNE now has a replacement bearing and procedure for the 997 IMS, but cannot find the reference anymore.

since i'm in the middle of a similar procedure, i'd be interested in your progress with pics if you are able. I notice the chain tensioner paddles coming up again in discussion (with respect to cause or effect)

Quotes source post: 10654111

I am planning on ordering most parts this weekend and then I will leave for a three weeks holiday on Bali. Hopefully the parts will all be in after return, so will start assembly then. But please feel free to pm me.

If I were into the engine that far I would look at their non bearing pressure fed bushing, IMSolution. Similar to the other end of the IMS. http://www.flat6innovations.com/

I would love to use the pressure fed solution, but as far as I know that is only available for a select group of shops. So I don't see any way to get my hands on this. On evaluating the parts, I now also found damage to the oil scavenge pump on the left bank. It was still turning, but cage in which the gear runs has broken. The other oil pump is undamaged (but will probably replace both).

Is your car covered under the current IMS settlement? "Model year 2001 - 2005 Porsche 911 vehicles manufactured with an IMS between May 4, 2001 and February 20, 2005"

Probably not as this settlement is under US law and I live in the Netherlands

I think the settlement is in California, which isn't really part of the USA so it's worth a shot. At the very least give Jake Raby a call or PM here on the boards. They have so much experience with this.

What about the triple row IMS bearing? Is that component that must be installed by Jake and his crew?

Quotes source post: 10653641

Answer is 3 none of the above & 3 as in triple-row bearing! Ship your IMS to LN so they can perform their IMSB triple row bearing upgrade service to your IMS. To anyone that would like to learn the facts instead of internet forum hearsay: lnengineering.com

Or you could listen to Jake Raby, and many others here who have actually done this job.

Some time has gone by, disassembled the engine, started to accumulate new parts, send out the block for new liners, went on holiday. After return, work kept me from doing much, but all the parts have arrived and also the engine case came back this week with nice new liners. Some of the damaged items I came across on disassembly and parts cleaning: - The chain tension did not operate smoothly, a ridge was worn in the bore preventing the piston to fully retract. - The chain tensioner paddle was broken - The IMS worn the bearing on the oilpump side - The left oil scavenge pump had a broken cage - The left variocam adjuster featured one damaged tooth - And obviously the IMS bearing itself was destroyed. Now wondering if the broken IMS caused the rest of the damage or if it all started with the worn chain tensioner. The list of new parts is long and expensive, but I am looking forward on starting assembly hoping to still do some driving this year before the winter really kicks in.

Looks like the bearing wore enough for the center stud to break then all the oil poured out the hole onto the ground. IMS started moving around breaking the IMS chain "paddle". This allowed more movement wearing the opposite end of the IMS & the tensioner jetisoned it's spring when the cast paddle broke metal got loose & lodged in the head scavenge pump. Send your IMS shaft to LN for the triple bearing upgrade, it is only installed onsite, buy their billet IMS paddle too. Check your coolant housing for excessive wear on the IMS bushing part, & also the oil pump housing. Every single part of that engine you are reusing should be cleaned Ultrasonicly to remove metal grit or else...

Quotes source post: 10790059

Thanks for the good advice. The tensioner did not jetison its spring, it was still on one piece on disassembly. I took it apart after I discovered it did not operate smoothly. I used a LNE bearing and billet paddle, also the oilpump housing, oil pump and oil scavenge pumps will be replaced with new parts. I made some good progress this weekend, the case is back together and pistons are installed on both sides. My biggest worry was installing the circlips on pistons 4 to 6, but that was actually relatively easy. Next up the heads and camshafts.