timing a '96 3.0L Mercrusier

[cbradd]

I have the EST ignition where all of the timing advance is done in the module. The engine is way too advanced at idle (about 20°) which makes it hard to start and diesels after key shut off. Shift interupter switch is set right and works as designed. Timing is set as outlined in manual (jumper wire on two leads at distributor and shift interupter switch wires connected together). I suspect the manual is wrong about shift interupter switch wires together (this would be the same as switch closed-hey it's a Clymer manual). So do I have bad advice from Clymer or do I have a bad module? Thanks in advance, no pun intended.

 

[Trent]

Re: timing a '96 3.0L Mercrusier

The manual is correct. Make sure you do your jumping with the ign. key in the off position. Time to 1 degree BTDC. After timing disconnect jumpers and rehook shift switch. Recheck timing at idle. It should be 12 degrees + or - two degrees at idle. At 2400-2800 RPM the max timing advance should be 27 degrees BTDC + or - two degrees.

 

[akriverrat]

Re: timing a '96 3.0L Mercrusier

deiseling has nothing to do with timing. key off-no spark. early or late. throttle not closing far enough or carbon buildup in cylinders most likely suspects.

 

[akriverrat]

Re: timing a '96 3.0L Mercrusier

http://www.marinemechanic.com/site/PAGE257.htm

 

[cbradd]

Re: timing a '96 3.0L Mercrusier

thanks. Question: does the jumper go on while engine running (like manual says) or prior (with key off)? Also, if I follow proceedure, I've done it right, but when I remove the jumper, the timing goes like 30° at idle (and won't re-start). Sounds like the module is #@%$^^. When I bought this boat last year, someone had the jumper on there and I didn't realize it was just supposed to be temporary till I started reading the manual. <br /><br />Yeah, I agree on the carbon build up. Any tips on correcting situation?

 

[Trent]

Re: timing a '96 3.0L Mercrusier

My mistake. Do as the manual says. Some systems you jump before the key is on.