cambria

Today I put my cams in according to the WSM. After tensioning the belt, notice that the notch on the 1-4 was not going to rotate in alignment with the backing plate notch, when I rotated the crank to TDC. The notch will be 180 degrees out. The cams were installed with the noses up on 1-4 and 5-8. The cam lob profiles lock the same as shown in the WSM. However the adjustment guages were discontinued from 87 on. The cam marks on the chain tensioner sprocket ( noses in my case) look like they should point outward. 1-4 on mine will both point to the DS. That is another indication to me that cams 1-4 are 180 degrees out.
I just researched 138 posts on cam timing and I could not fine one that addressed a S4 cam installation. Any help would be appreciated.
Thanks, Terry

Imo000

You need to rotate the crank shaft twice for the cams to re align again.

Big Dave

Maybe these will help:

Installing Cams
Basic Cam Timing
Precision Timing

Jim_H

Damn that's a nice write up.

Gary Knox

Big Dave,
That is a FABULOUS writeup on cam installation, timing, etc. THANK YOU for pointing it out to us. You all might be aware, but just in case: PorKen has developed a really neat tool for timing the cams on the 928 engines. Not very expensive, and makes the job much simpler. Earl Gillstrom (captearlg) and I replaced the cams on my engine last winter, used both the method that Big Dave shows for timing, AND used Porken's tool simultaneously. Found that Porken's tool was "spot on" for accuracy, and from that point on we did and will use it primarily.
Gary Knox
West Chester, PA

cambria

Dave, thanks for the imput. I did follow you timing belt issue through your engine rebuild and have bookmarked your web site. I think your write ups and photo's were very complete and I thank you for doing a good job.
Yesterday I did re read the info on cam timing and every thing I did looks correct. Im000 sugested rotating the crank 2x for the alignment, but I think if I do that I will crush some valves. So what I plan to do today is since 5-8 look good I am going to remove the cams for 1-4 and rotate to see if I can get the sprocket marks to align.
Thank for your responses.
Terry

cambria

Gary, I do have Ken's tool and plan on using it when I get to that point. What MY is your car?

SharkSkin

That's an interesting writeup, though the third page seems to skip a few steps regarding the actual fine adjustment -- it jumps from "loosen the cam gear bolts" to "Rotate the crank several times and keep re-checking the gauge". I assume that the missing step goes something like, "Then loosen the three bolts slightly and adjust the cam position relative to the gear using a wrench on the cam flats as shown in the pic".

While I don't currently own a 32v car, I do plan to... thus my interest...

cambria

I am still in need of help. I have had these cams every which way but backwards. I have started at the begining following Dave's writeup and have and have setup the cams using the WSM, and can't get the notches to align with the backing plates. The only way I can get the notches on the sprockets to align with the notches in the backing plates is to set the cams up to do so while the the no. 1 piston is at top dead center. The noses are generally pointing away from the engine, not up or towards the engine. The intake lobe has passed the open position. I have rotated the crank at varrious settings to see if it will line up but no banana. I will be lucky if I haven't bent a valve.

Gary Knox

Terrence, et al,
Sorry - my engine is an '88 S4.
Gary Knox

WallyP

The cams are initially installed with the crank at the 45 DBTC mark, with the marks on the cams at the drive chains aligned with the marked links on the chains. (Some cams have cast humps instead of marks.) The marks on the cam sprockets will NOT be aligned at this point.

After all cams are installed, you turn the crank 45 degrees to bring it to Top Dead Center - Firing for #1 Cylinder. The notches on the cam sprocket should now align with the marks on the backing plates.

If you turn the crank one turn, the notches on the cams should be 180 degrees away from the marks on the backing plates.

When you turn the crank another turn, the notches on the cam sprockets should align with the marks on the backing plates.

At this point, it would be good to precisely align the cams using the procedure in the manual (dial indicator, etc) to get them really right. Basically, you set the crank at the proper position, loosen the cam sprockets, then turn the cams to the correct lift, then tighten the sprockets. After that, the cam notches will not be precisely aligned with the marks on the backing plates, but the cams will be correctly timed. Porken's tool works well after that.

cambria

Wally P, thanks you for your response. This is the first time I have tried to post Pics. All of the pics are with the crank at TDC. The yellow marks are the pully notches or cam noses. I have checked part numbers and with the exception of the last 2 digits are spot on.

cambria

Well, I think I have solved my problem. I had gotten hung up on the cam noses being in the upright position when installed into the head. This is how the WSMshows the cam installation. I think the noses only searve two uses, to align the cams with each other and to show the relationship of the cams when pointing to either the intake or exhaust when setting the lifter rise on #1 or #6.
What I have done is set the crank at 45 degrees and adjusted the cam sprocket to 45 degrees BTDC. When I rotate the cam to TDC the #1 piston is in the compresson stroke, and rotated 360 back to TDC puts the intake cam lobe just past the firing of #1, which is they way it should be. After many rotations of the crank everything appears to look good.
Now I need to determind if I have bent any valves during my education on setting up cams. Thanks to everyone who responded,Terry