Timing and spark advance help

[gakpuss]

I have a 1969 merc 800 Ser#2669700 and I have been trying set the spark advance for a year. I have a service manual for it and I have read Clams Casino's description of the sync and timing procedure but I can't get a grip on it. The service manual has some special rules for this model. I am one step away form taking it to a mechanic. I have turnned the crank until #1 is a TDC and alligned the solid line on the flywheel with the distributor pulley. That seems to jive OK. Then when I "advance the vertical arm" which I believe means move the shift lever forward to advance the timing mark, the three dots, to 27 degrees BTDC but I can't even get close. I am at about 70 degrees BTDC. I am fairly sure the flywheel is in the right location. Please help.

 

[gakpuss]

Re: Timing and spark advance help

Here is a little more information. When I purchased the motor it did not have the plate with the three adjustment screws that bolts to the distributor. I purchased a twin to my motor for parts and took the plate off it and put it onto my motor. I have replaced the plugs, the wiring harness and the ignition wires along with a bunch of other mechanical repairs including; carbs, fuel pumps and water pump. I have no idea how it ran before I got it. I also have no idea what was done to it before I got it. Is it possible some wire is on backwards? Would a bad condensor cause it to discharge early?

 

[Laddies]

Re: Timing and spark advance help

Maybe I can help heres some things to check, see that the TDC mark on the decal is lined up with the short cast line marked with a 6. The white line on the flywheel should line up with the arrow on the dist drive pulley (the one under the plate not on top) at that point the 3 dots should line up with the TDC on the timing decal. for now were not going to worry about anything but Max spark advance. I don't care what you have read try it my way it may be differant but it works for me. Pull the spark plugs from the engine and make sure they are all grounded well and hook up your timing light, if you don't have a remote starter button to turn the engine with you will have to remove the throttle cable to advance the spark advance to the stop. If you have a battery charger hook it up and with it running spin the engine and adjust the timing to 21 degrees BTDC. (3 dots)
Now we will set the primary pick up plate with the timing lite find 5 to 7 derees BTDC, at that point the primary should just touch the primary lever on the carb, if it has to be adjusted you will have to loosen the 2 bolts that hold it to the dist to move it.
Next we will adjust the secondary pickup lever, without the engine turning over advance the dist to the max spark stop and turn the adjustment bolt on the throttle actuator plate to just touch the the carb cluster.
Last advance the throttle to WOT look down the throats of the carbs and set them to to wide open position with the throttle stop screw. Hope this helps

 

[gakpuss]

Re: Timing and spark advance help

Laddies-Thanks for the reply. It did clear somethings up for me. TDC on the decal lines up with the 6. When the three dots are at TDC the solid line is at about 23 degrees BTDC. When the arrow on the dist pulley lines up with the solid line on the flywheel the three dots do not line up with TDC on the decal they are about 13 degees ATDC unless I turn the arrow on the dist pulley to about 2 o'clock and line it up with the solid line on the flywheel. Does that make sense?