Exhaust Temp Issue

[pwgsx]

While backing the boat off the trailer this weekend the temp light came on but then off a few seconds later. I didn't think anything of it and took the boat out to test a oil pressure sensor issue- that's another story! The temp light didn't come back on and I thought all was fine. However I got home and looked in the engine bay and the waterbox looked like the paint had bubbled. I then looked at the J pipe and the plastic thread hose protector ( see pic) was melted. I have never seen this before on any other ski. Where do I need to be looking for water restriction? I went ahead and hooked up the CanDoo and found the max engine temp was 203 and the other engine was 196 ( both seem good there). The exhaust temp on the one with the melted plastic and bubbled waterbox was 208 where the other engine showed only 177. :cuss:
This new boat has not been enjoyable yet!!

 

[Coastiejoe]

While backing the boat off the trailer this weekend the temp light came on but then off a few seconds later. I didn't think anything of it and took the boat out to test a oil pressure sensor issue- that's another story! The temp light didn't come back on and I thought all was fine. However I got home and looked in the engine bay and the waterbox looked like the paint had bubbled. I then looked at the J pipe and the plastic thread hose protector ( see pic) was melted. I have never seen this before on any other ski. Where do I need to be looking for water restriction? I went ahead and hooked up the CanDoo and found the max engine temp was 203 and the other engine was 196 ( both seem good there). The exhaust temp on the one with the melted plastic and bubbled waterbox was 208 where the other engine showed only 177. :cuss:
This new boat has not been enjoyable yet!!

There is an elbow that is just before the head. This elbow seems to catch debris and cause a restriction. Once it is restricted the engine temp goes up. Many have had an over-heat issue due to the elbow holding onto debris. Pretty easy to clean it out at least.

 

[pwgsx]

Is it the elbow shown in my pick that the rubber hose connects to? IF not can you point me in the direction of where to look?
thanks

 

[Coastiejoe]

Is it the elbow shown in my pick that the rubber hose connects to? IF not can you point me in the direction of where to look?
thanks

Not where I can look at the photo right now. I was referring to the cooling hose that goes from the pump to the cylinder head input side...

 

[pwgsx]

I just looked it up, I think I see what your talking about. I might just pull each exhaust manifold and give it a good cleaning and inspection. I have a feeling this boat was used in salt a few times. The further I am digging into it I keep finding indications of salt use.:facepalm:

 

[pwgsx]

Pulled the main waterbox and J pipe and didn't find anything plugged up. The paint on the box peeled right off so I know it got pretty hot. I found the secondary box was turned a bit and the upper exhaust hose was kinked pretty good. I would say about halfway so there was a pretty good restriction. Here is a pic but it really does not show how bad it is bc its kinked on the backside. Would this cause it to overheat?

 

[pwgsx]

Well I got around to pulling the manifold off and found all the lines to be clear. Blew them out with air anyways and flushed with water with no issues. Pump screen is clear as well and I blew air thru that too..... I am down to 1- the temp sensor is bad but that doesn't explain the bubbled paint or 2- the kink in the hose attached to the resonator was pinched so much it wasn't allowing the hot gasses to exit. I want to bypass the resonator completely but not sure.

 

[Coastiejoe]

Temp sensors fail all the time. But I agree, does not justify bubbles paint. Sounding like it was the linked hose.

 

[pwgsx]

Its been too cold here to work on it but I removed the resonators and am going to pipe from waterbox straight to the exhaust outlet when it gets warmer

 

[pwgsx]

Just a final update if anyone is having the same issue or wants to remove the resonators........Got everything back together and decided to bypass the resonators altogether. Here is a pic showing how much the pipe was kinked. Lastly got pics of the final install. Hope it all works