Camshaft Deviation

[redeye280z]

I finally got the chance to check my camshaft deviation on a 2000 Boxster S and found Cam 1 at -4.38 and cam 2 at -8.42 should I be worried what does this really mean?

[NewArt]

Deviation is out of spec. Usually worn chain ramps (plasticky guides that put tension on the cam chains). The Parts don't cost much but it's a labour intensive job. I Did mine last year when I dropped the engine. Mine were 5.x and 9.x ; much better now. I Can't say it changed the way the car runs. Maybe better gas mileage.

[Heiko]

Your CAM bank 2 is 2+ deg past manufacturer spec allowance.
Probably nothing serious just yet but unless you go in and change the vario
cam sliders this is going to get worse!!! Eventually the chain will eat through
what's left of the sliders and then it will get expensive! Not a bad job and it
can be done with the engine in the car :-)

[KRAM36]

Do you guys know of a guide on how to change them with the engine in the car?

I'm sure redeye280z would like to see it.

[redeye280z]

Wow wasn't expecting this should I be doing anything else if I go in and change the worn out sliders?

[clickman]

Yes. Replacing the 4th and 5th timing chains.

One guide is in the Pelican Parts tech section:

Pelican Technical Article: Boxster Camshaft Upgrade / Chain Tensioner Replacement - 986 / 987

Not an easy job with the engine in the car.

[clickman]

This is an interesting thread showing what can happen when one of the chain sliders in a M96 breaks. The relevant posts are #65 and 70. It doesn't end well. I find it disgusting that this part is made of plastic.

Dragged home one of these. - Rennlist Discussion Forums

[JFP in PA]

Originally Posted by clickman

I find it disgusting that this part is made of plastic.

They are plastic on every car, even Ferraris.

[DG Boxster]

I just got a Durametric and mine are -3, -9. I'm glad to hear that this is a possible to do myself. Has anyone written a DIY guide on this?

[KRAM36]

Originally Posted by DG Boxster

I just got a Durametric and mine are -3, -9. I'm glad to hear that this is a possible to do myself. Has anyone written a DIY guide on this?

Did you check it with the engine fully warm?

[steved0x]

Originally Posted by KRAM36

Did you check it with the engine fully warm?

Fully warm as in a hard drive, not after a 5 minute drive while you wait for the coolant temp arrow to get to the 180. I have done that and got an artificially high reading that freaked me out.

[DG Boxster]

Well I drove around for 20-30 minutes, but not "hard", shifting at maybe 4000.

I just now changed the oil: after 5000 city/highway miles it was a beautiful clear brown with nothing in the filter or on the magnetic plug. The engine just turned over 80K (I think it is the original) - its hard for me to think that there is something majorly wrong...

[NewArt]

There are lots of instructions available but I'm not sure if there are specific "in car" how-tos. Having done the job with the engine out, I can't say as I would relish the prospect of doing the same job with the motor still in the car, especially for a first timer.

[thom4782]

While you're in there, consider changing out the variocam solenoids. Not that expensive and you'll have done most of the labor already.

[steved0x]

Originally Posted by DG Boxster

Well I drove around for 20-30 minutes, but not "hard", shifting at maybe 4000.

I just now changed the oil: after 5000 city/highway miles it was a beautiful clear brown with nothing in the filter or on the magnetic plug. The engine just turned over 80K (I think it is the original) - its hard for me to think that there is something majorly wrong...

I think 30 minutes is enough to get it fully warmed up so your measurements should be good.

[Ptriggiani]

When fully warm as previously stated, would you typically expect the numbers to decrease or increase from cold readings? I mistakenly just warmed it up in the garage while idling and found the numbers to increase slightly from cold start readings.

[steved0x]

I've never checked them cold but when I check when the car is not fully warmed up the deviations are greater.

[Ptriggiani]

Well I finally got a ride out of my new toy purchased in November and put to sleep immediately due to old man winter. I was able to warm it up completely as suggested previously and checked the deviation values after the ride and found both readings to drop approximately 1 degree bank 1 went from -5.54 to -4.45 bank 2 went .from -8.75 to -7.77 from the readings taken by warming it up in only in the driveway This was after 1/2 hour of light to moderate driving limited by frost heaves. Car ran great, I think I am going to monitor the readings for a while before I jump into anything.

[Heiko]

-7.7 is still beyond the limit... Personally I would not gamble on making them last until something happens.... I'm just sayin' and that's only my opinion!