mercrusier 4.3L TKS engine timing

[jcraigw]

Engine starts and runs fine at idle, but bogs at acceleration over 1000 rpm. Cleaning carb tomorrow. Would like details on procedure for checking and setting engine timing (degrees ?); Model is 1A301134.

 

[alldodge]

Howdy

Timing is set 2ATDC (yes after TDC and not before)
On one of the plugs on the distributor there should be three wires and two of them are not connected to anything. Warm the motor up then connect those two wires together with a jumper and set timing

Edit: almost forget disconnect the shift interrupter leads when setting timing. then connect the two leads removed from the interrupter switch together

 

[jcraigw]

Thank you. I am new to mercruisers. Okay to use my induction timing light, not blow up the electronic module?

 

[alldodge]

Sure, no problem

 

[jcraigw]

Well, have make significant progress with the 2008 4.3 L mc bayliner. Really appreciate the input. Completed new carb kit install, new plugs, drained and checked tank for contaminants (none found), 2nd new fuel filter (no water in new removed filter), new distributor cap and rotor (fixed engine acceleration bog at 2200-2800 rpms). Rotor was so rusted on shaft, had to split it to remove. Still have not checked timing but reviewed more literature. Apparently the 2008 TKS has a single wire coming off the electronic module with a rubber plug that requires grounding to get base timing. New info did not mention need to connecting the shift interrupt leads.
The response that the shift cutout leads need to be shorted is confusing. Logic would indicate that connecting these leads would short the ignition system and prevent engine from running. Would have the same effect as when the switch is activated in shift from forward to reverse???

Can't find any timing plates/marks on the crankshaft so having done timing. To recover timing marks or creating them on pulley by setting the #1 piston at exactly TDC on compression is difficult Thinking maybe my inductive engine analyzer for electronic ignitions, that provides dwell, would work as well w/o need for timing light. ??
Last question; the new distributor cap has a small hose fitting installed on side. Does this have any function since ignition advance is done by the electronic module? Would like to plug and eliminate moisture getting into housing, reduce shaft rusting.
Thanks again for all the input.

 

[alldodge]

With TBV ignition just ground the pru/wht wire before you start the motor. Don't bother with the shift interrupter switch or wiring. Let it warm up then set timing at 10 BTDC

Bring damper around close to TDC then take some sand paper to it, I'm thinking its painted over.

The fitting on the side of the cap is to allow air in so the moister can be burned off from heat of the motor. If you seal it up, this will make things worst.

 

[jcraigw]

Thank you. Appreciate you're ignoring my dumb dwell comments. Been a while since I worked on anything but computerized ignitions and OBD code readers.
Taking her out this week end for an extended test. Runs smoother and has better acceleration after oil is up to operating temp, about 20 min and 2200 rpms. Thinking the lifters may be marginal and seals not working well until oil is hot, but there is no chatter, even when engine is lugged.