Peter 642

Jules didn't drive no German car, although Mr. Wolf did have a decent NSX.

Only if he can bill for it.

Palmbeacher

LN recently updated their website discussion of the retrofit to admit they've had 3 of their single-row bearings fail. At first blush one has to admire their overall honesty...of course, it does tie in neatly with their recommendation that even those with their LN retrofit should consider buying their Guardian Disturbingly, they also say that the latest retrofit bearings are being redesigned with a ferrous casing which would trigger the Guardian...leading to the implication that the Guardian won't alert to an impending failure of the existing LN retrofit bearing that most of us have installed.

Given the (relatively) small number of retrofits, 3 failures feels like it could be roughly the same percentage of failure as the OEM. I personally would like it if Charles and/or Jake could elaborate on those failures. Have they necropsied the failed bearings, and what is their conclusions?

Clearly to me, there may be numerous variables which complicate speculation about the LN bearings' longevity. One is the quality of installation, and another is preexisting engine conditions/failures-in-progress. It would be useful and informative to hear from the manufacturer regarding these failures.

From LN's website:

Jacks911

(e.g. you can not use a magnetic drainplug connected to a continuity meter
to tell you anything other than your engine is about to fail,
in which case it is usually too late),

That may be the case... but the author also suggests changing the oil at 15,000 as suggested by the manufacturer. So while Oil analysis is great ... who is watching the engine in between the 15,000 mile oil changes??? On an average Porsche that could be three years! Everyone has an opinion... so that is mine. P.S. I have an LN Bearing and Magnetic drain plug, and that makes me happy.

Charles Navarro

So far, only one engine failure has been 100% attributed to an IMS bearing failure, more exactly, the cage was what failed on the one that we had anything to analyze. Thankfully, that individual heard something and shut the engine off, preventing mass carnage. The other two (one as recent as last week), was driven until the engine would not run any more. The problem we have in the other two situations is that there are numerous things broken in the engine and it's impossible to determine what failed first.

With an open bearing, any debris in the oil will certainly make its way to the IMS bearing and can cause the cage to fail. That was one thing we always knew could be a problem, especially when users are installing retrofit kits on engines that have had bearings that are starting to fail or already failed. That's one reason we have such an elaborate warranty procedure to make sure there is professional installation and the bearing that was in there originally wasn't failed.

Having a product like the Guardian available to provide advanced warning is great, but owners need to be attentive to the sounds their cars make. Any advanced warning is only good if the driver makes use of the feedback provided, be it a CEL, warning buzzer, or mechanical noise outside of the norm. I've lost count of the number of times I've been told that the damage caused by a failure has been made that much worse because these warnings were not heeded.

All the dual row IMS retrofits have always used steel cages. The singles have used polyamide since it's the more common configuration for those particular ceramic bearings.

Given we've had about 4000 retrofits and upgraded IMSs in service for several years now and the only ones that have failed have been single row bearings (and we see more failed factory single row bearing IMSs), it's clear to us now that the single row bearing is the most flawed design. We have had zero upgraded MY06-08, triple bearing IMSs, or dual rows fail. Overall, the failure rate is still much lower than any of those figures we've seen quoted. The moment the first single row bearing failed, Flat 6 Innovations and LN Engineering immediately hopped back into researching alternative solutions to the IMS problem and right now we have two possible, however more complicated solutions to the IMS issue as a whole we are developing and testing.

The best explanation our bearing engineer and supplier have is that the single row bearing is insufficient for the loads placed upon the bearing. In the case of the only bearing that was even possible to be evaluated, the cage went first allowing the ***** to spread in the races unevenly, which there is only so long the bearing can operate like this. Considering the bearing had recently been installed, the cage itself probably had an internal defect.

Knowing this, I very well expected this to happen at some point, since these are mechanical systems and even with the best bearings from a trusted source, there certainly is a chance of a bad bearing being thrown in the mix that we have no control over.

Very well said. All concerns we have had throughout the process. You'd be amazed at the questions we get from shops installing retrofit kits and moreover, shops that probably shouldn't be doing this work. Most do not buy directly from us, but rather through a wholesaler, separating us from the transaction, allowing for more chances that someone, somewhere doesn't do an installation properly or worst, doing it on an engine that shouldn't be retrofitted.

We've also been able to extract used IMS retrofit bearings from engines that came apart for cylinder failures and the most recent had over three years and 36,000 miles on it, and was in perfect shape. Other bearings upon inspection have likewise been perfect.

Regardless of what people may say about the IMS problem, I've always tried to be as transparent as possible with everything I do. I'm always available by phone or email, or when directed, to threads like this, and I'm more than happy to answer questions to the best of my ability.

Palmbeacher

Thanks, Charles, for your considerate reply.

I have your single-race bearing in my engine. The shop who installed it is on your list of dealers, has installed many of the bearings, and has a good reputation in the area for building engines for track cars. They said they use the LN bearing whenever they build an engine, and have subsequently torn some of them down with over 50k miles and a proportion of it in heavy-duty track use, and found the bearings in like-new condition. They also showed me my old bearing (30K miles) and said it appeared in good condition, with an intact seal and no signs of imminent failure.

I have my oil and filter changed inside of every 6 months (my extended warranty requires it), which for me amounts to about 3500 miles. Although I only drive about 7000 miles/year, it's daily driving year-round, and my commute is long enough to get the oil to normal operating temp, and does not involve sitting in traffic jams. I try as best I can to keep the cruising revs above 2500, and always downshift if it drops below 2000. My upshifts typically happen in the 3-4000 range. Keeping the bearing flushed with oil, and changing oil frequently, I hope to prevent small particulate debris from attacking the bearing. Since my bearing has the synthetic cage, I find a less-than-compelling argument for installing the guardian.

A large number of the single-race OEM bearings seem to have survived to quite high mileage, which counters the assertion that it's underspecified for the load. Most likely it merely doesn't allow for as much deterioration to take place before it will no longer support that load. I was certainly hoping given the LN version's specifications (open lubrication, ceramic components and thicker bolt shaft) that it would easily surpass the OEM, so it's a bit disheartening to learn that it might not.

As you said, there is always going to be the possibility of a defective bearing. I've got a year and nearly 7000 miles on mine, so hopefully it's not one of them. Certainly if my car needs another clutch in another 30K miles (although the shop said it should go twice that or more, the pedal gets quite stiff as the plate wears) and you have a better solution then, I will consider it. I do hope the current bearing lasts that long. I'm grateful I went ahead and got the extended warranty.

logray

dresler

Most importantly, I think Marc is referring to Dirty Harry, not Pulp Fiction.

Marc Gelefsky

I was paraphrasing the "say what one more goddamn time" from Pulp"

But I could work up a good Dirty Harry upon request

Marc Gelefsky

yeah, Im bored.

logray

Nice!

dresler

Oh, Please put that in the sticky!!

BSonwine

Who is the bigger badass Jules or Harry?

Peter 642

On hair-doo alone, Jules, hands-down.

j beede

LNEng IMSB is no miracle cure. If there is any "magic" it is LNEng's extractor which allows many IMS bearings to be replaced without engine R&R and teardown. That is all. Rear tires every 10,000 and replace the IMSB with each clutch.

rb101

And he has a wallet like this: