928 79 SLC

putting the timing belt on my '79....crankshaft is set at TDC, drivers side cam set right on the mark...but the passenger side cam is about half a tooth off (about two dots .. off)...any suggestions would be appreciated....thanx in advance.

the flyin' scotsman

Did you spin the engine a few times, by hand , and verify the positions?

Its easy to advance the cam if off................other wise start over.

Bill Ball

There is no adjustment for this as the relationship of the right and left cam gears is fixed by the belt that is strung between them, and the left cam gear positon relative to the crank is fixed in the same manner. On most cars the two cam gears are right on or very close, but on some one cam is off a bit. As long as it is less than half a tooth off, that's as good as you can do.

PorKen

'78-'79 cams use Woodruff keys to locate the cam gears. You can use Mercedes' offset keys to line them up, or even advance/retard them.


thread

Bill Ball

Just to be clear, that offset key will allow you to change the CAM timing, if needed, but the left and right cam GEARS will still be in the same position relative to each other. That's determined by the belt tooth.

918-S

The offset key will rotate the cam back in phase while allowing the gear to line up on the mark on the back housing. The offset keys will need to be shaped to fit into the cam as they are a different shape.

Oh ya, 79 cam..

PorKen

Cam gear won't line up, cam will. Just like 32V cams/gears.

'78-'79 cam keys are half-moon shaped, '80-up use this type:

Bill Ball

The bold part won't happen unless you somehow MOVE the GEARS further part or closer together or change the size or position of the water pump pulley. In theory, the gears should line up if everything is factory. If the heads have been shaved, they no longer will.

Dennis Wilson

The belt is going to stretch over the first 1000 miles with the passenger side moving the furthest. That's why the WSM tells you to put the mark clockwise from the pointer if not centered. Then check it after breakin to make sure it is properly aligned.

Dennis

Bill Ball

Nearly all belts I have done have been right on right out of the box. In doing Dennis' motor, we are off a bit, at least some due to head shaving.