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Timer pointer adjustment on 86 Merc 150 hp blackmax

D

duhn

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"I am trying to do a link and

"I am trying to do a link and sync. The first thing the Seloc manual tells you to do is adjust the timer pointer. has anyone done this before? The instructions do not make any sense! What is the purpose of turning the motor counter-clockwise? There are dozens of models that have different instructions. Mine is on page 6-37, model 150 serial # 5203429 and above."
 
Do to the relationship between

Do to the relationship between the crankshafts rotational motion and the pistons reciprocal motion there is a slight amount of crankshaft rotation were the piston remains stationary at TDC. This is further increased with wrist pin and rod journal bearing clearances. Setting the indicator to 0 at the pistons TDC and then backing off beyond .464 and bringing the piston back to exactly .464 eliminates bearing clearance and more acuratly determines TDC in crankshaft rotation. I have often felt that this is splitting hairs. Bring the piston to TDC and slightly rock the flywheel back and forth while watching the indicator. Split the difference in crank rotation were the indicator does not move and set the pointer to TDC. For all practical purposes that will be good enough.
 
As a side note I have seen num

As a side note I have seen numerous water pump impellers improperly oriented and stuck in that position due to rotating the engine against the normal direction of rotation. Although its not a common occurance it can happen.
 
"Thanks, I think I figured it

"Thanks, I think I figured it out. The manual is missing one important step. When TDC is found with the the dial indicator, The timing pointer should be set to zero! The manual never tells you to set the pointer to zero. Thats where I got confused... you are told to use the pointer as a reference during the counter clockwise procedure when it hasn't even been set.

Thanks for your help"
 
"The pointer is adjustable, lo

"The pointer is adjustable, loosen the two screws and set the pointer on 0 when you get the #1 to TDC. As Allan said, The 'freeplay' you have by moving the flywheel back and forth and staying at TDC by dial indicator is the happy place for your pointer. Make sure to hand turn the flywheel by hand clockwise a couple times to ensure the impeller on waterpump are in the right direction."
 
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