1999 911 996 M96 Variocam Ramp + Chain DIY

[logray]

I recently purchased Wayne's 101 projects for Boxster and love it! I can't wait for the 996 book :)

For those of you that haven't purchased the book available at the renntech Amazon store. To date, I believe Wayne's chapter 16 on camshaft swap and valvetrain repair is the best I've seen as far as a step by step walk through. The only thing I can see that he recommends that might be an issue is using a magnet instead of the lapping tool to remove the lifters, since there is a TSB explaining it is bad to magnetize the lifters. The chapter in the book though certainly has empowered me to feel confident enough to tackle this in my own garage. I have heard mention of a couple other DIYs but haven't found them in their usual places. I also found this awesome website called project nutrod, this thread over on 986forum on timing the M96 as well as these youtubes on the boxster s complete engine rebuild (I'm not planning to do a complete engine tear down and valve job/etc though...).

I have been steadily tackling Jake Raby's pre-failure directives 1 by 1. At ~72k miles I've replaced the H20 pump (72k), IMS & RMS (68k), (RMS also at 38k) and AOS (55k). When I had the sump plate out at 68k there looked to be a small amount of tiny tiny bits of black/orange variocam pad guide on the bottom of the pan. I'm sure the pads are scored and ready to be replaced.

I'm at the point where I'll have the engine out and have a tentative list put together.

1. The variocam ramps
2. 4th and 5th chains
3. Variocam solenoids
4. Any lifters that might be worn
5. Possibly the 3 chain tensioners unless they look OK (although when I had my 1-3 tensioner out for the IMS it did look a little scored). Although it's unclear what version to use, new or old.

Questions I have regarding this DIY.

1.) Of course many people have done their own work using various work shop manuals/etc. Has anyone followed this particular step by step yet with good success (boxster or 996)? Having already done the LN IMS swap, I would rate that at a 6/10 on difficulty (first time through). How would you rate this in difficulty compared to an IMS retrofit?

2.) Am I wrong to assume nearly all of the Boxster DIY in the 101projects book applies to a 1999 3.4L M96 engine (assuming most if not all since my 1999 motor is also a 5 chain).

3.) If I have the engine apart (aside from cracking the case in half), is there anything else I might want to tackle while I'm in there. Updated case bolts, oil filler tube, etc.

4.) I haven't found a recommended parts/shopping "list" that applies to a 3.4L M96, I understand there are some shared parts with a smaller Boxster engine. Example I know I'll need the P253 timing tool, chains, new pads, cam caps, various gaskets & rings. Here's what I've come up with so far... Appx $1k in parts not including lifters which adds ~ another $1k for all 24. I've also read if one is bad that all of them on that side should be replaced?

P/N,Desc,Qty,Notes

P253,"Porsche Timing/""Lock"" Tool",1 (or fabricate my own)

CAM SERVICE

996-105-170-53-M48,intake to exhaust chain,2,(the chains on my bicycle cost 2x this but I won't complain so please don't raise prices)

996-605-901-00-M100,1-3 Solenoid,1,optional/peace of mind

996-605-902-00-M100,4-6 Solenoid,1,optional/peace of mind

996-105-253-00-M100,Cam pads/guides,2,(assuming 2 per kit and includes o ring?)

996-105-223-52-M204,Solenoid cover,1,(I already replaced 1 of them @ 70k since it was leaking)

996-105-041-72-M40,Lifter/tappet,24,(as needed/if worn)

996-104-215-54-M100,Cam plugs,6,(might have one laying around)

TENSIONERS (see TSB 1551 or this thread for which tensioners you will need based on your year car and engine)

900-123-147-30-OEM,Tensioner crush ring,3

996-105-180-54-OEM,Old style IMS tensioner,1,Still affordable

996-105-180-56-OEM,New style IMS tensioner,0,Not applicable for my engine serial number

996-105-051-58-OEM,Old style 1-3 tensioner,0,Costs more than the entire project ($1k)

996-105-186-01-OEM,New style 1-3 tensioner,1,Supersedes the old part above

996-105-053-58-OEM ,Old style 4-6 tensioner,0,Costs more than the entire project ($1k)

996-105-188-01-OEM,New style 4-6 tensioner,1,Supersedes the old part above

SPARK TUBES

996-105-325-52-M100,Spark plug tube,6

999-707-343-41-M17,Spark tube inner ring,6,(might already have these)

999-707-215-40-M17,Spark tube outer ring,6,(might already have these)

000-043-205-10-M100 ,assembly grease for spk tubes,1,Any good alternatives here this stuff is expensive?

MISC

999-217-150-09-OEM,new oil scavenge pump bolts,8

999-707-554-40-M17,oil scavenge pump o rings,2

997-101-212-01-M17,rear main seal,1,Unless it's dry I might as well do the RMS again

999-073-092-02-M260,new flywheel bolts,8

900-123-106-30-M131,oil drain washer,1

900-219-009-30-M260,oil drain plug,1

900-123-144-30-M131,coolant plug crush washer,1

999-707-409-40-M17,oil cooler ring,2,heard they can start to leak

999-707-389-40-M17,oil cooler ring,2,heard they can start to leak

997-110-247-00-M30,intake manifold gasket,6,(I should have replaced these when I went in from the top to do the AOS)

5900,Loctite flange sealant de jour,,"as needed for machined surfaces, I think I have some copper permatex which was dharn's suggestion"

PEL-KM34155,Kimwipes,,Recommended by Wayne (read the book).

,aos hose,1,(a pesky miniscule leak I can't reach unless I drop the engine)

,Acetone,,To clean machined surfaces

,Assembly oil,,special assembly lube such as ultra stick

Edited May 6, 2011 by logray

[xmac]

I would be the first to admit, that I am inclined to do all same work on my '99 C4 - thanks for the list and links. I too would love to do everything on your list but just a word of caution. Take a look and read this March 2011 Sport Aviation Article:

EAA Sport Aviation

We did some work with Dr. James Ignizio, noted in the article, at a company where I was responsible for maintaining many multi-million dollar pieces of manufacturing equipment. We did find the same results as in most of the research that people cause Waddington Effect (overmaintining) by "fixing" things that might break.

That said, I am also in NorCal and if you need a hand I would be happy to help.

Edited July 19, 2011 by xmac

[logray]

Cool deal and thanks for the link! I haven't had a chance to read it yet but certainly will.

I am a big fan of if it ain't broke don't fix it, but if there is a problem, it needs to be addressed.

I've since done all the work, the car is back on the road, and I certainly found problems while I was in there... worn valve guides, worn chain ramps, broken oil filler tube, among other things.

Here is the thread on rennlist!

http://forums.rennli...ures-later.html

And a similar thread here on renntech.

http://www.renntech.org/forums/topic/38771-rr-engine-cams-and-heads

If you decide to embark on this it's quite a drive for me to Silicon Valley from near Auburn, CA.

As an additional note, while Wayne's book is GOOD, it is not 100% complete and no job such as this should be attempted without lots of help from these forums as well as a copy of the genuine work shop manual.

Also the parts list above grew substantially after I started tearing down the engine.

Edited July 20, 2011 by logray

[xmac]

That's funny, this popped up on the front page in the "Recent Post" box and I didn't notice you posted it in April. Thanks for the links as I will be carefully reading them and also for posting all of the pictures.

I just picked up my car 3 weeks ago and have barely put 500 miles on it. It only has 22,500 miles on it as the previous owner was saving it for me by not driving it. :) I did the basic oil change and checks and the only thing I plan to tackle soon is the spark plug tubes and diff/tranny fluid change.