Rough Idle Video

[NeverAgain3]

125 hours total. 100 hour done at 90. From what I’ve found on here it’s plugs and/or coil packs. Runs good above idle.

I had a cooling hose come off at WOT a couple of days ago. Got the alerts and shut it down and got towed. I forgot about the no-wake (first problem in 5 years) restriction but most of the tow was no-wake zone. Oil clear and full. Put stainless clamps on the hoses and it ran good today other than the choppy idle.

rough idle.mov

 

[Cobra Jet Steering LLC]

Time to inspect ALL the clamps including all the exhaust hose clamps and remember to try to keep the reverse hood UP when being towed to reduce the back pressure of the water flowing through the pump and being pushed into the cooling line pickup.. If memory serves me correctly This advice was first mentioned a few years ago by one of our members SWATSKI .

 

[Scottintexas]

That certainly doesn’t sound good

You didn’t have any idle issues before the tow ??

I would normally say start with the plugs and see what happens

If you did get water up into the cylinder I don’t really know how that would cause rough idle but smooth top end

@Neutron

 

[Cobra Jet Steering LLC]

I would believe the electrical conectors got soaked I would unplug as many as you can find and one at a time spray them with silicon spray and then plug them back together then soak all the wire harnesses with the silicon spray and see if the issue goes away . This is what I use and you can get it at walmart it does not have any solvents in it like others do and it works great. Funny but years ago here in Florida I would keep this in my brief case in my police car and when we had heavy rains people would break down after driving through deep water in the intersections. I would have them open their hood and I would spray their ignition with this and magically the car would start up instantly and they would look at me in disbelief. I also sprayed it on my patrol car engine so I would not get stuck.

 

[Neutron]

I would believe the electrical conectors got soaked I would unplug as manu as you can find and one at a time spray them with silicon spray and then plug them back together then soak all the wire harnesses with the silicon spray and see if the issue goes away . This is what I use and you can get it at walmart it does not have any solvents in it like others do and it works great.
View attachment 212440

I second this, is the water sprayed onto the electrical components, it could cause problems. Compressed air and wd40 works great.

Was there water everywhere or just locally?

Did the air filter get wet?

 

[NeverAgain3]

I found this thread. His motors sound like mine. His fix was the Rubber Shaft Coupling.

https://jetboaters.net/threads/1-8l-engines-missing-vibrating.35556/

 

[FSH 210 Sport]

I found this thread. His motors sound like mine. His fix was the Rubber Shaft Coupling.

https://jetboaters.net/threads/1-8l-engines-missing-vibrating.35556/

Did you read @Scottintexas post?

 

[NeverAgain3]

Did you read @Scottintexas post?

Yes. I’ll start with the plugs. It’s had very little use in the last 8 months…less than 4 hours. The dipstick was all oil so I don’t think any water got in. Got smooth revs above idle to full throttle at 7600 rpm. I’ll check electrical connectors and the air filter also.

 

[NeverAgain3]

***UPDATE***
It looks like new plugs for the win! Here is an old plug picture. They all looked the same. Much smoother idle on the hose. No time for a water test today. Thanks for all the suggestions.

AfterPlugs.MOV

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