Question on possible failures

[midcarolina]

So... here is the story, I have a 94 mariner 115 has always ran great except for the usual rough 2+2 idle. This morning I decided I would do the gallon of gas and can of seafoam treatment to clean up carbs/top end, got everything set up put muffs on cranked her up walked back to motor and noticed water spraying out just below the number one spark plug hole! Upon visual inspection I can see part of the head plate gasket sticking out.
I know it's hard to say for sure but does that sound like more than just a head plate gasket failure?

 

[flyingscott]

There is no head gasket on that motor. That is just a water jacket, easy gasket to replace. That motor also shouldn't be idling rough the 2+2 is a pretty smooth idling motor.

 

[midcarolina]

Yeah I'm aware there's just water under the plate , I was just asking if that gasket failure could be the result of another issue ... on the idling just about everything I have ever read as far as complaints of this type model is rough idling.... I'm certainly no marine mechanic but it seems to me if a 4 cylinder is designed to idle on 2 then any small issue will be magnified.

 

[flyingscott]

Did the motor overheat at all? Otherwise it's as simple as a gasket failure, may want to replace that. As far as the idle is concerned that's up to you if you want to put up with a rough idle. I owned one of those motors for 15 yrs still one of the best idling motors I ever owned.

 

[midcarolina]

no over heating... and honestly I couldnt really tell you how long it's been going on, can't say when the last time I had the cowl off and muffs on..

 

[racerone]

Rarely do folks go over a motor and snug up bolts.---Yes I take a lot of motors apart and find loose bolts.----Gaskets then fail.------Rough idle ?----Start with a compression test and post your results.-----They made that model for many years so doubt that they all left the factory with rough idle.------Perhaps some fine tuning of slow speed jets on # 1 and 2 is required.---No slow speed jets to adjust on # 3 and 4

 

[midcarolina]

Pulled the cover today a straight edge revealed no warpage of the cover....cleaned up the mating surfaces, pulled the plastic cover off the ignition and coils noticed a tan with blue strip wire with terminal end just hanging around...traced it back to the high temp. sensor, looks to me like it should land on the terminal block that has a tan/blue stripe wire going to the controls...Is this the correct termination for the wire?

Thanks