merc 85hp cant set max timing

[jvoldarski]

trying to set max timing on my 75 merc 850 and i am unable to do so because the screw bottoms out before i can get the timing mark alligned... could i have accidently put the timing belt a tooth over when putting it back on... would that cause my problem. it idles fine by the way.

 

[Chris1956]

Re: merc 85hp cant set max timing

There could be several things that are out of whack. Set the motor to top dead center on the top cylinder, using a screwdriver. The timing mark should indicate nearly TDC on the flywheel. If not the outer flywheel is misaligned. With the flywheel showing TDC, set the cast arrow on the distributor pulley to point to the dot on the flywheel. Install the belt.

Now recheck the idle pickup timing. it should be 4-6* BTDC. Max timing should be 21* BTDC.

 

[merc850]

Re: merc 85hp cant set max timing

Here's the procedure for initial timing
You have to set the pointer at .464" BTDC with a dial indicator or 15/32" by ruler.