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Timing a 150 mercury

duramax

New member
"I have a 1997 v6 Mercury 150.

"I have a 1997 v6 Mercury 150. I checked the timing today. My procedure was; I used a dial indicator to make sure my timing pointer was adjusted right. I disconnected all spark plugs and instead of using a spark gap tool, I used old spark plugs and made my own wiring harness and grounded them out. I disconnected the idle stablizer cranked the motor over and the reading I got with an inductive timing light was 9 instead of 21 as the manual indicates. What did I do wrong or can the motor run that far off time? And could you please explain to me in the carburetor section of my service manual it says idle speed/pickup timing is between 2 degree and 9 degrees ATDC. What does this mean? Thank you"
 
Pickup timing happens at idle.

Pickup timing happens at idle. There is an S-Cam and roller for the throttles. The pickup timing is where the two make contact.

0-9°ATDC at idle.
21° BTDC is probably the max. (DO NOT EXCEED THE MAX)

The max. is set with the throttle pushed open of course. The split arm has a small screw for idle timing and a big screw for the max. The big screw will hit the stop peg and the arm will keep going to open the carbs.
 
"Hi there,

ATDC: After Top


"Hi there,

ATDC: After Top Dead Centre. Crank is pulling piston away from sparkplug, commonly known as the "bang" cycle. In two strokers this is also the exhaust cycle.

BTDC: Before Top Dead Centre. Piston is squeezing the fuel mixture for ignition spark.

Hope this clears things up a little?

Regards!

Benjamin."
 
I dont know what I did wrong t

I dont know what I did wrong the other night but when I did it on friday night I was able to get it timed. Thanks for the help.

Ray
 
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