Overheating/limp mode

[kasey200]

On the weekend of the 4th we surfed for about 3 hours right when we got to the lake and then for some reason the boat smoked an impeller. The temp gauge hit about 200-210 and the warning buzzer came on. We got a tow back to the trailer and the following morning in replaced the impeller.

Ever since then it just hasn't been the same. We went out last week and cruised back to our riding spot and the temp was good the entire time. I just idled the last 1/4 mile of the trip so i could fill the ballast. Once the ballast was full we were ready to surf. The first rider got in the water and away we went, or so i thought. By time the boat go to speed it had overheated again and shut down to an idle (Limp mode??). I shut it off for 10 min and then it started normal. I decided we would not push it and just head back to the trailer. The whole trip back to the trailer i watched the temp gauge VERY closely and it never got over 175 varying the speed the entire trip. Does this sound like an impeller again? To me it almost seems like the gauge is messed up and throwing it into limp mode. Next time i go out i'm going to take a heat gun and check the temp of the heads to see if the gauge it correct or not.

[a1paintnbody@hotmail.com]

I had a problem with my 21v.the belt on the motor would get wet and slip allowing the motor to heat up.I found this because when the temp would go up the volt gauge would go down it was slipping on the altinator as well. Put a new belt on and made sure it was good and tight. We have not had any more trouble. Hope your fix is as simple as mine.

[kasey200]

Thank you i will check that out.

[kasey200]

should i run it on a fake a lake in the driveway? that way i should be able to see water comeing out the exhaust. That should tell me if the impeller is good or not.

[scoot18]

The failed impellar; was it in tact or shredded? Were any of the vein parts missing? These may have moved up into the water jackets and may be causing a flow obstruction.

Running it on a fake lake is a good idea that way you can monitor the water flow out of the exhaust, see if it is ample enough.

[chpthril]

The failed impeller may have been caused by a blocked intake hose. This would explain why the engine still overheats.

[Tanner]

In addition to what cheap said, you may wanna make sure the bearings in your impeller housing are ok.

[kasey200]

The impeller was shredded pretty good. I will do my best to try and find a blockage somewhere. I got several of the viens but it was hard to tell if i got them all. I am going to run it on the fake-a-lake tonight and see what happens.

[R&T Babich]

.... I got several of the viens but it was hard to tell if i got them all. ...

Something is restricting high water flow.
You might need to backflush the cooler that is right after the pump.
The temp sensor for the alarm is different than the sender for the gauge.
I put a brass Gano coolant filter in the water line after the pump to catch impeller debris.
There seems to be sufficient water flow as the temps were 174 deg before and after installation.

[kasey200]

Something is restricting high water flow.
You might need to backflush the cooler that is right after the pump.
The temp sensor for the alarm is different than the sender for the gauge.
I put a brass Gano coolant filter in the water line after the pump to catch impeller debris.
There seems to be sufficient water flow as the temps were 174 deg before and after installation.

Thats a good idea. I am going to try to get it flushed out tonight. Where did you get the Gano? I've used them for a vehicle in the past but i believe i had to order it.

[R&T Babich]

... Where did you get the Gano? ...

I got it off ebay 3 years ago.
It slips into the outlet hose.
It's easier to remove the pump outlet hose on our boat at the cooler to get the pump out so I can check the filter at the same time.
http://autocoolantfilter.com/index.htm

[kasey200]

As far a flushing the lines out where is the best place for a guy to start? at the trans cooler and work back?

[kasey200]

do you think this could have anything to do with it????

lol.. pulled out of the trans cooler.

[kasey200]

thanks for the help guys!!

[R&T Babich]

Is that a clump of weeds?
I'll bet that took out the impeller.
I added this raw water pickup strainer to keep junk out of the pump.
There were two pieces of cardboard the size of a stick of gum in the V-drive that had made it thru the pickup grille.
On our boat (maybe all) the raw water goes thru the V-drive casing before going to the raw water pump.
It's a cast SS bucket with a perforated SS basket inside and a plexiglass inspection plate.
Picked it up off ebay in 2007 and haven't seen any since.
There are several other styles on the market.
At the end of a season I clean out the basket and it is always has a layer of seeds and twigs in it.