Overheat at wot new water pump manual no help...

[krisnowicki]

I was out yesterday first time with less then 5 people in the boat so i wanted to see how fast the boat would run. GPS in hand i run it up to 5400 rpms with a 21 pitch prop. After about 4 or 5 mins the over heat alarm comes on and immediately shut off. Let it cool of and started it back up and ran for hours at 4500 or less with no over heat on the way back in i run at 5200 and it overheats again. It seems only over 5000 will it over heat. The boat has a new impeller on it and i flush constantly. The manual says it may be the tstats but they did ok in the boil test in the manual. What else am I missing? The boat pees strong enough to cut a hole in concrete.

 

[krisnowicki]

Re: Overheat at wot new water pump manual no help...

sorry this is a 92' 200hp v max counter rotating

 

[zzzzz]

Re: Overheat at wot new water pump manual no help...

sounds like it's time to pull off the cylinder heads and clean the cooling passages in the block and in the cyl heads - you'll have to split the heads and water jackets apart to fully clean inside...find a shop with a bead blaster(like sand blasting) and see if they'll clean the heads

 

[krisnowicki]

Re: Overheat at wot new water pump manual no help...

would slat away or anything like that work. I flush ever time and run mostly in fresh or brackish water...

 

[James R]

Re: Overheat at wot new water pump manual no help...

May be a lubrication problem, not enough oil being delivered.

 

[krisnowicki]

Re: Overheat at wot new water pump manual no help...

I was thinking not enough oil.... would to little to not enough lead to this? I had just put gas and oil in...

 

[krisnowicki]

Re: Overheat at wot new water pump manual no help...

Also, if i had some gunk in the water jacket, wouldn't the pee stream be week.

 

[James R]

Re: Overheat at wot new water pump manual no help...

The pee stream as you call it is no indication that water is running around the waterways correctly, only that the pump is pumping.
The telltale is there to tell you of a failed pump impeller for the most part.

 

[zzzzz]

Re: Overheat at wot new water pump manual no help...

if you have any kind of build up in the cooling passages-it causes turbulence in the water flow making air bubbles thus not cooling as well