If it's like it's later 115 and 150 cousins:

There is a "nib" on the bottom of the pulley and a corrosponding "nib" on
the block where the distributor mounts through. When those two nibs are
lined up the thing should be at TDC on #1. (In practice it's like 4 degrees
before TDC)

HOWEVER, since it *does* run and idle, I'd bet it all that you are off by
only ONE tooth. Just slip the belt off the top of the distributor and
retard it by 1 and you outta be all set. If you had the idle OK before you
started, then it will be real easy to tell when you have the belt back where
it belongs.

Once you have all that fixed, you should set max advance at WOT to 34
degrees before TDC.

-W

"Matt Lang" wrote in message
om...
Guys,

I got my Merc 1250 running fine. Then I decided to change the timing
belt which is very loose. While doing this the belt slipped and I
lost the timing.

According to online stuff for smilar motors the timing has to be set
by making the arrow on the distrubutor pully point to the line on the
flywheel.

When I did that the motor idles very high (3000 rpm).

There is a whole bunch of marks on flywheel and pulleys but i dont
know how they have to be ligned up.

Does anybody know? (this is a 1969 I6 motor, Thunferbolt ignition)

Any help appreciated (the dealer wont touch this motor


Matt