Rough Start and Shut Off

[millz90]

So i replaced my ditributor cap, new plug wires, and new plugs on my 1995 175 Series but when i start the engine it rocks the entire boat, like shakes, and does the same a little when i turn the engine off.

What does this mean? Is it out of timming, or need the distributor turned/adjusted?

Any ideas would help...Thanks!

 

[Captain Crispy]

If you didn't do anything to the timing when you you replaced parts, it isn't timing causing the shaking.

Sounds like you crossed a couple wires, or one [or more] of the wires is not securely fitted to the top of the plug or the cap.. Go back and check whether each wire goes to the correct cylinder and make sure each wire is snapped in tight to the plug and cap.

 

[millz90]

It doesnt shake horrible but when its starting the engine does shake the entire boat. Do you happen to know where a wiring diagram would be for the plugs? Im pretty sure i connected them the same way. I was told it needed a tune up?

 

[millz90]

No crossed plug wires....everything is tight and in the correct order?
Could it be the carb?

 

[tdappleman]

If you made no changes to the carb, I would initially focus on the recent work. I'd pull each plug and double check the gap on each as well as ensure there is no physical damage to the ceramic insulator. Did you also replace the rotor when you did the cap? Any moisture present in the cap? Check the new cap for any signs of damage - may be something on one of the contacts preventing good transfer.

 

[JediJD]

If you have a new symptom after replacing parts, you have to confirm the parts before assuming something else has randomly broken (its the old "if you hear the sound of thundering hooves, think horses...not zebras"). Its pretty easy for a plug to go south in a new installation...a bent electrode, a cracked porcelain, a loose end cap...all very easy to happen to the best of technicians. Its also very easy to break a spark plug wire in a marine application. If you pull the plug end off by the wire, it can separate. The easy check for them is to use an ohmmeter and confirm that there is generally conductivity across the wires...if the engine is running, then the actual amount of conductivity is not as important as the wires being generally equivalent. Take your time and confirm you have known good parts from which to operated.

If the parts are good, and the wiring wasn't crossed, look for a broken vacuum line. "Dieseling", the common term for a run on engine, is quite often a function of a vacuum leak (before I get rebuked for this, it can also be caused by a number of other things, but I look for vacuum leaks first).