Dharn55

Here is a link to Baum Tools pdf of the timing tools they sell.

http://www.baumtools.com/pdf/porsche_timing_tools.pdf

If you look at the Camshaft lock #9612, it is essentially the same as the Porsche tool. It bolts to the head with the center red ****, then it fits into the exhaust cam and it held in the grooves with the red **** on the right. Then you rotate the arm until the black piece on the left fits into the opening on the head/cam cover at the intake cam. So with this tool you can lock the crank at TDC, loosen the bolts on the cam sprocket, and then rotate the cam to the correct position, then tighten the bolts on the sprocket.

With the tool in the set shown in #1 the cams must be in the correct position for the tool to fit, all the parts of the tool are "stationary" so you cannot rotate the cam with the tool. Thus with this tool you must get the cams to the correct position, install the tool, then loosen the bolts on the sprocket, move the crank to TDC, then tighten the bolts on the sprocket. No other way to do it that I know of. This tool goes for about $216, the Baum tool is more like $400.

Jake Raby

I always rotate the crank.. Mush less chance for issues that way.

insite

do you always rotate it forward, or do you sometimes rotate it backward a few degrees to reach TDC?

my concern is that if i lock the cam & rotate the motor backward a tad, i'll introduce some slack in the chains & the timing will be set improperly.

logray

When you R&R the pump drive, did you just have to relieve the tension on the chains and shafts by removing the three tensioners? I'm a little wary now of doing this considering yours jumped a tooth... but I think I would feel better about this if I have the engine apart (aside from cracking the case) with the cams removed.

OP or Anyone else here have some guidance or experience?

I am considering R&R the oil pump drive when I have the cam's out to replace some noisy worn lifters with 72k miles along with variocam pads and small chains on my 1999 3.4L.

Thanks.

insite

I had other circumstances that caused the issue. The job is straightforward; just be sure to pull the tensioners BEFORE you pull the oil pump. Since you'll have the cams out, you'll need to re-Time anyway.

Where are you getting your lifters? Replacing all, or just some?

logray

I'm still shopping around for lifters, but the going rate seems to be around $18 for the BMW P/N. If I have success I'll share it here. And yes I think I'll be replacing all, especially after reading about how it takes a trained eye to determine how much usability is left in them.

Yes I certainly plan to do the driver once I have the cams out... now whether I have both sides off or just one bank at a time - I'm guessing as long as all of the tensioners are out, it should be smooth.

There's also a few pix of the pump rebuild from Glen? @ 986fix.com

http://www.986fix.com/photos.php?view=thumbnailList&category=14

logray

Can you detect this slight timing slip in the drivers seat as a very slight occasional random wobble - perhaps every 5-15 seconds, not like a misfire, but more like the engine stumbles ever so slightly and then it corrects (rpm doesn't change, just the slight little rumble/wobble). And while it seems to disappear and completely smooth out above about 1000 rpm (at least in my car it is actually very slightly detectable even above 1000 rpm - holding my breath and concentrating to feel it, or pretty much sitting on the door sill). I broke out the Durametric yesterday and logged some data after the car was warmed up, and my engine has 72k miles on the clock.



For what it's worth, I swapped the (20k old) coil packs and (10k old) plugs from bank 1 to bank 2 and still feel a little tiny wobble every so often at idle. Camshaft deviation is constant -3 on bank 1 and 0 on bank 2. T/B is clean, AOS replaced, LN IMS retrofitted, fuel additive, no vacuum leaks. Also read it could be chain stretch... but after reading this I bet the timing is not 100%???

insite

What's the y axis here?

logray

Good question. If I understand correctly?, basically it is a value assigned by the DME based on a number of factors, which are basically summarized by the following??? Proper engine timing would result in near 0 value where improper timing/detonation would result in a value greater than 0, and at some point as determined by the DME, a rough running value observed greater than the threshold would result in a CEL (and other gremlins).

However, I am certainly not an expert... just an enthusiast. It would be great if an expert could chime in.

The 996 WSM for a 3.4L states the following regarding warm idle rough running acceptable values.

Rough running threshold should be at 9.2.
Deviation +/- 1.3 (1/s squared)

Rough running should be at 0.
Deviation +/- 1.5 (1/s squared)

I suppose the whole air/fuel/spark/compression/vacuum formula probably also contributes here...

Google "rough running value"

"Method for detecting combustion misfires and cylinder equalization in internal combustion engines with knock control. The invention relates to a method for combustion misfire detection and cylinder equalization in a multi-cylinder internal combustion engine having knock control. In the method, rough-running values are individually determined for each cylinder by measuring segment times with each crankshaft rotation. The segment times include the times corresponding to the piston movement of each cylinder to be measured in which the crankshaft passes through a corresponding circular-segment angular region. Thereafter, the determined rough-running values are compared to a threshold value in a desired value comparison and, on the basis of the deviation between the determined rough-running values and the desired value, cylinder-individual equalization factors (that is, correction factors) are computed in an evaluation unit for the change of injection times or ignition time points of the individual cylinders. It is provided that the computed equalization factors (GL1) for the change of injection times or the ignition time points or the charge serve as the basis for the determination of a rough-running increase value (LUTcorrected) effected by the change and that, with the determined rough-running increase value (LUTcorrected), a computation of a corrected rough-running value (dLUT) takes place. The corrected rough-running value (dLUT) is utilized for the computation of the final equalization factor (GL2) for influencing injection times or ignition time points or the charge."

vza

Have been searching far and wide for step by step instruction for timing on a 5 chain. Completed IMS and RMS replacement on 99 boxster base.I have To pull my cam cover to replace a solenoid and want to check and reset timing if needed.Did your step by step method work.... I'll be using the 9612 tool the P253tool didn't work for me....it had issues. Please let me know if you had any success. Yours is the 1st simple list that makes everything clear. Thanks in advance. V

808Bill

Not sure if you realize you opened a 8 year old post.