Dispeling M96 engine rumors

[Lil bastard]

It's always interesting how receptive people are to news they want to hear.

I'm not saying the OP isn't well meaning, or that he's necessarily incorrect. But rather than dispel any rumors I think he's only added more fodder.

Not that he isn't skilled, but we're talking about 1 tech from 1 dealership, and at least some of what he's said contradicts info and data coming from Flat 6 and LN Eng. and also from a source which long predates F6 and LNE and established info and fixes on some of the nagging issues of the M96 motor back in the late '90's - Autofarm in the UK.

If the Type M96 plague hasn't struck you, you're probably more likely to side with Brian PT.

But, if you're the proud owner of an alloy boat anchor manufactured in Stuttgart, you're likely to remain somewhat more skeptical.

[clickman]

^^^ Trust LB to burst my bubble.

[Perfectlap]

Brian,

can you briefly describe what sort of training a Porsche mechanic receives say right out of tech school and what sort of on the job training/clinics you receive each year?

[Lil bastard]

Originally Posted by clickman

^^^ Trust LB to burst my bubble.

Not at all!

And, I'm not trying to play Al Pacino in some Keanu Reeves movie either.

It's just that some guy, with a grand total of some 2 posts initiates a thread labled "Dispeling (sp) M96 engine rumors ", adds that he's a Porsche Tech and people (well 13 out of 14 anyway) are ready to follow him like he's the Pied Piper of 986ville!

I'm not saying he's wrong, but as he himself points out, he attempts to "dispel some of the rumors that seem to be running rampant".

At least to my mind, he was not successful.

IMS isn't the only issue here. What about RMS, faulty ignition switches, weak waterpumps, window regulators, seat belt latches, plastic rear windows, convertible top push rods, and on and on? The OP didn't address a single one of these.

Granted, IMS failures may well be the 'pancreatic cancer' of these cars, especially the mid-gen cars (that's not exactly a revelation). But what comfort is that to those who suffer merely from the 'prostate' or 'melanomic' varieties?

[Dragonwind]

I think the biggest one for me, and despite the respect I have for Jake, is the lifters issue. At first he claimed it was robbing power, now in another post he mentions it is fuel economy and no car dyno'ed gave more than 1hp gain. My mechanic who has rebuilt many a M96 motor hasn't seen these problems. And if it were MPG then why does my 99 still get the same MPG that it was rated for 10 years ago with 89k on the OD (and I keep her in the high revs)?

Chris

[Jake Raby]

Originally Posted by Dragonwind

I think the biggest one for me, and despite the respect I have for Jake, is the lifters issue. At first he claimed it was robbing power, now in another post he mentions it is fuel economy and no car dyno'ed gave more than 1hp gain. My mechanic who has rebuilt many a M96 motor hasn't seen these problems. And if it were MPG then why does my 99 still get the same MPG that it was rated for 10 years ago with 89k on the OD (and I keep her in the high revs)?

Chris

Like I said, there are no blanket statements that can be made with these engines and their issues. Some cars that have lifter issues make much more power after they are remedied.. Others lose MPG but never really lose power, and some engines make more power from the factory than others.

It has a lot to do with how many lifters are bad and if they are on the intake or exhaust valves.

What I said was:

I recently had a car show up here with 22 of 24 lifters bad, after our work the MPG jumped up 5 MPG, but the power didn't change more than 1HP and 1.5% average torque.

Note that is ONE instance with one car. Some engines that we do this work to do pick up power, I have seen as much as 6HP and 11 lb/ft of torque but the biggest difference is the torque and HP plots and their smoothness. In a lot of instances the average power output is increased across the board, not just at peak output and the dip at the variocam changeover point is greatly reduced with the lifter upgrade.

If you have decent gas mileage and decent power don't worry about the lifters... They'll never fail and leave you on the side of the road.

[cnavarro]

Ok, the lifters might be one of those "while you are in there job," but again, sometimes it's needed. It's a known fact that the wear pads for the variocam on the pre-vane cell adjuster engines are typically worn out by 60-80k miles. So, while you are in there, it's easy enough to pull the lifters and check them while replacing the wear pads and chains. If you end up needing some new lifters, why not replace them all? Or third option, rebuild the set of lifters rather than replacing them- a cheaper third option.

I'll continue to add to the list - chain tensioners. They have been revised and updated, and again, some at even low mileage have excess clatter at startup that may be a lifter or lifters or the chain tensioners. Retail, they are not even that expensive. We reused a set of low mileage tensioners on my 2.9 and even with an accusump pre-oiling the engine, I can hear them. So this winter, they are getting swapped out for new ones. Lifters were new since all of them were bad on the low mileage donor.

This isn't a problem isolated to the M96. Our W8 Passat with 55,000 miles has it's engine out for failed chain tensioners, thankfully under powertrain warranty since it's an 8-10k repair!. Makes the M96 look downright inexpensive to repair!

Unfortunately, frequent oil changes alone aren't a cure for lifters and tensioners. Hell, my W8 had it's oil changes every 5,000 miles (10L fill, half the factory drain interval) with Motul every fill and the tensioners still failed.

We just have to learn to deal with what we are given and work within those constraints.

[Dragonwind]

Originally Posted by Jake Raby

If you have decent gas mileage and decent power don't worry about the lifters... They'll never fail and leave you on the side of the road.

Thanks Jake and fair enough. I'll deal with them in a few years when it is valve job time. Maybe by then I'll drop in one of yours.
Chris

[GEARHEADTX]

I am new to the forum and owner of 2003 Boxster. I was fully aware of the IMS shaft failure issue when I purchased the car used. I am also an engineer and in my line of work, statistics mean a lot. In many discussions on this topic, I have seen many sad stories as I am sure I would have shared if I had experienced the same problem but what is missing in these stories are the condition of the car, service history, and statistics regarding this problem. I realize we all hold a very high expectation for these cars given their pedigree and the company claims however, they are much better in terms of design compared to other cars in their class. No one has really shared the statistics of this problem and conditions under which this problem occurs. I am sure if you browsed the internet, you would find similar or comparable stories of failures in other high marquee cars such as BMW and Mercedes. Ferrrari's are notorious for failures but people buy and drive them because of what they are not because of how many times they have to fix them.

[Brucelee]

No stats available.

Who would supply them Porsche?

[mikefocke]

Publishing stats would be like admitting there was a problem, they were aware of it, and they were tracking it.

And it would be raw meat for plaintiff's lawyers and salespersons of competing brands.

Not to mention I don't know of another company who has made public such statistics except while under lawsuit from a well financed legal team.

I don't think we'll ever learn em.

[jmatta]

What ever happened to Brian Porsche Tech, AKA "The Phantom"?

2 posts and gone (or lurking under another name, yet again?)