Dennis Burford

Hi guys,

Diving into my timing belt, hope to get it (and some other things) done by SITP.

On my current (old) timing belt, when crank O|T is lined up with indicator, the notches on the camshaft sprockets are one belt tooth off the notches in the timing belt backplates.

Engine was running great. Should I keep the same offset, or should I line the notches up correctly? What's the effect on one tooth off? (Sorry I can't remember whether it was one tooth before or after the notch, I'll look tonight when I get home).

Thanks,
Dennis

PorKen

The gear notch is not always a good indicator of the actual cam timing. You need a 32V'r to check it accurately.

Check if the rotor bolt holes are roughly centered in the gear slots. This will show if the notch is somewhat accurate.

I've seen many cases where a mechanic, having strung the belt a tooth off, will max out the gear slot to 'fix' it.
There is more than a 15 degree range in the slot!


One tooth advanced will make it very perky at low rpms, but it will quickly run out of breath at higher rpms.
Retarded will make it comparatively sluggish over the entire rpm range.

davek9

Yep, you can not go by the gear notches on a 32 v eng. Like Ken stated they are adjustable independent of the actual cam timing.
Without a 32vr cam tool, you needs to remove the cam covers and adjust per the shop manual.
Maybe someone in your area has one ?

Dave

Bill Ball

Deniis:

Unfortunately my 32vr tool is out on loan. If this is how it was before you changed the belt, I'd leave it for now. Hey, MAYBE we could do this as a tech session at SITP if I can get my tool back before then (should be able to).

Dennis Burford

Thanks Ken, Dave, and Bill. Looks like I need to get a 32vr timing tool. Bill - Most everything is already off the front of the motor, I'm ready to pull the belt, so as a tech session I'm a little ahead of the game, unless I want to have her towed over to SITP (not exactly how I planned on arriving).

The more I learn the more I don't know. I've tackled quite a few challenging repairs on this beast, but this may be the holy grail of 928 repair initiation.

PS Bill, Your Avatar is looking much cleaner of late, nice to see your car whole again!

jcorenman

I'll bring mine, just in case...

Dennis Burford

I finally processed what Bill was saying, not ever having done a TB before. If I can't get the timing dead on (read: if I can't get my hands on a 32vr tool) I'm open to refining the timing at SITP. Now the pressure is on to get her back together.

Dennis Burford

Hi guys,

Bill, thanks for the offer of timing my cams at SITP in a tech session, but it looks like my shark is not going to make it. Roger is backordered on Porkensioners, doesn't expect them in until later this week at the earliest. I'm not sure I'll get it in time to put the car back together and get it down to Berkely on May 4. I may have to drive the Camry, ewe.

We'll see what plays out ....

Bill Ball

Argh!

I have a spare Porkensioner, but I think that might be a little too ambitious for a one hour tech session.