'96 Sears Gamefisher 9.9HP by Force - tuning to 'happy medium'?

[jim j geezer]

Model: 225.581998
Serial: OE128531

I've run it in a test barrel, but yesterday was the 1st time I've had it on a lake. Started OK but failed to plane out my 12' semi-V. The load was a full 6G tank of fuel, a fullsize (big & heavy) marine deep-cycle battery, front-mounted foot-control trolling motor, me (about 185#) and some fishing tackle & beer. I placed the fuel tank & battery just forward of the rear seat.

Fiddling with the single mixture control I was able to get it to just plane, but found it idled rough and seemed to miss on 1 cylinder. (Got it to max speed then riched it up maybe 1/8 turn)

1. Possible dirty or mis-set points on 1 cylinder.
2. I need to check & compare compressions.
3. Possible fouled plug.

Is there some voodoo Jedi mind trick to setting that single mixture adjustment?
Thanks
Jim J Geezer

 

[fishrdan]

Re: '96 Sears Gamefisher 9.9HP by Force - tuning to 'happy medium'?

Hmmm, Yoda say,,, BIM coil check and fuel pump rebuild be done

Being a 96 it should have BIM coils, which are known to go bad, so check spark on both leads with a spark tester, hot blue/white spark. Ethanol likes to eat old rubber parts, so rebuild the fuel pump. I didn't have any issue tuning the carb, but guessing you have a fuel it spark problem. Defiantly change the plugs if they are carbon fouled. You could also do a de-carb with come SeaForm, clean up the inside of the OB.

I have a whole lot more gear than you, and I'm fatter, and have no problem planing my 14' jon boat with a 7.5 Gamefisher. Though, jon boats plane easier than V-hulls. You could play with weight distribution in the boat (move weight forward) though it sounds like an outboard issue

 

[jim j geezer]

Re: '96 Sears Gamefisher 9.9HP by Force - tuning to 'happy medium'?

"One step forward..."

*PHOOEY*

Pulled the plugs and did a compression check: Top = 112; bottom = 114 <--I regard that as good/acceptable.
Looked at the NKG BP6HS plugs and they seem to be in serviceable condition. That said, I have a preference for Champions. Did a cross-reference. The NKG crossed to no fewer than SEVEN Champions!
L66Y
L82Y
L82YC
L82YCC
L87Y
L87YC
L87YCC

The Champion sits said that marine-rated plugs use a wire-wound resistor. Anybody know why?

 

[jim j geezer]

Re: '96 Sears Gamefisher 9.9HP by Force - tuning to 'happy medium'?

Just a follow-up on the Plugs. Searspartsdirect sells the Champion L82YC as their replacement. Still curious about that wire-wound resistor for marine use.

 

[fishrdan]

Re: '96 Sears Gamefisher 9.9HP by Force - tuning to 'happy medium'?

Dunno much about Champions, but to steer clear of them. I'd use NGK's, if you go to their website, they have a catalog where you can look up the correct plugs.

For sears parts catalog, use that to look up the part numbers, then shop elsewhere. Sears might have extra digits added to their P/N's IE: a ABC123456 might be Mercury part number C123456. Crowley Marine is another good place to look up parts, and buy them. Iboats is a good place to buy also.