9.8 timing procedures

[pontoon chief]

Can anyone help me out with the timing procedure for a 9.8 merc,mid 1970's ?
I had a timing light on it and saw were the timing mark at idle was way to the left of the timing window at idle.When I raised the RPM's to half throttle I could get the timing mark almost to the left side of the small window.Is there a link and sync procedure for this motor ?

 

[Laddies]

Re: 9.8 timing procedures

It's a little difficult to pin drop excally as the were 3 differant setup used on the mid 70 models but basically start the engine put it in forward gear (if you free rev it you will blow it up) go to WOT and set the timing either on the flywheel mark or 34 degree which even engine you have. Some the cab pickup aren't adjustable some are, if it's adjustably then set it a 5 to 7 derees ATDC