IMS Bearing install Question?

[dirkdiggler]

I am going to be replacing my Clutch, flywheel, motor mount, o2 sensors and installing the LN IMS retrofit kit next week.

I have read a few DIY on the IMS bearing and was wondering if it is crucial that I get the CAM lock tools and lock it while I am replacing the bearing???

Some DIY say too do it and others do not mention locking the cams... just wondering if it can be done safely/easily without locking them?

thanks guys!

[coreseller]

When I did mine, I did not lock the cams. I had emailed Jake Raby (which is what you should do, or Charles at LN) and he instructed me to lock the motor via the front pulley, completely remove the 2 REAR chain tensioners, then do the R & R. Wayne Dempsey from Pelican later explained that I should of locked the cams, maybe I just got lucky . Anyway, the car has a few thousand miles on it since without issue knock on wood.

[JFP in PA]

The answer has more to do with what type your engine is: Five chain (up to 2003) or three chain (later years). The three chain motors are much more prone to jump time if not "locked down" during this procedure than the five chain motors............

[dirkdiggler]

ok, mine is a 1997 so it obviously has the 5 chain

is it pretty easy to lock the motor via front pully?

or is locking the CAM's the real only way to insure no issues

should most shops have the tools too lock the cams?....or are ones for Porsche special?

thanks for the help thus far guys!

[JFP in PA]

The tooling to lock the cams is unique to Porsche, and not cheap (about $250 per side). With a 5 chain, you can "probably" get away without locking the cams; that said, the only 100% certain method is to lock them with the tooling. Give Charles Navarro at LN a call, he will walk you thru it……..

[dirkdiggler]

what are things I can avoid doing when removing/installing the new IMS bearing that will "help" prevent the cam from jumping gears?

[JFP in PA]

As we are not fans of releasing the chain tensioners without locking the cams (having seen what can happen if the cams move), I would suggest talking to Charles Navarro or Jake Raby on the best method......

[Cloudsurfer]

Being a 5 chain motor, you SHOULD be ok pulling the tensioners with the crank at TDC without locking the cams, but I'd emphasize "should" in that sentence. I've had a cam slip a tooth on a 3 chain motor when a tensioner was pulled, and had to go back and re-time the engine.

[dirkdiggler]

ok, thanks guys

anyone else ever lock the cams by the via the front pully on the front of the motor before? like coreseller mentioned above?

[JFP in PA]

Pinning the front pulley locks the engine at TDC, it does not lock the cams. To do that, you pull the green plugs out of the cam covers and use one of these:

[clickman]

[QUOTE=coreseller]Wayne Dempsey from Pelican later explained that I should of locked the cams, maybe I just got lucky QUOTE]

Interesting. You look at his procedure, at the link below, and it seems like the cams don't have to be locked, but the IMS sprocket should be. I suppose in reality it's the same thing, as long as the chains are tight enough.

You also don't appear to NEED P253 with this method.

http://www.pelicanparts.com/techarticles/Boxster_Tech/14-ENGINE-Intermediate_Shaft_Bearing/14-ENGINE-Intermediate_Shaft_Bearing.htm

[Gilles]

Very interesting reading, thanks for the link..!


[QUOTE=clickman]

Originally Posted by coreseller

Wayne Dempsey from Pelican later explained that I should of locked the cams, maybe I just got lucky QUOTE]

Interesting. You look at his procedure, at the link below, and it seems like the cams don't have to be locked, but the IMS sprocket should be. I suppose in reality it's the same thing, as long as the chains are tight enough.

You also don't appear to NEED P253 with this method.

http://www.pelicanparts.com/techarticles/Boxster_Tech/14-ENGINE-Intermediate_Shaft_Bearing/14-ENGINE-Intermediate_Shaft_Bearing.htm

[AndyA6]

http://boxsterguide.blogspot.com/2010/09/intermediate-shaft-ims-bearing-info-and.html


This will help.

Later,
Andy

[JFP in PA]

Just to put a cap on this debate, with a five chain motor, it is possible to swap the IMS without locking the cams. That said, in doing so, you still run a level of risk of the M96 jumping time. While they don't always jump time, they still can, and sometimes do. The reason shops lock the cams is that we are not in the business of assuming risk; locking the cams assures there will be no problems, period.

It's your car. If you want to accept the risk, then don't lock the cams. In most cases, you will probably be fine; but if it goes wrong, you are going to be in for some very expensive fun.......

[insite]

i had this discussion w/ charles last week when i ordered my IMS bearing. he said that indeed we SHOULD lock the cams, but that generally, not doing so, as long as the motor is locked to TDC, will probably be okay.

his advice to me if i choose NOT to lock the cams (which i will not, btw) is to pull the green plugs & mark the cam positions. this way, if i jump time, i will be able to tell that it has occured & have the problem rectified before i fire it up & cause damage.