Water temp
 

A little history...I bought a 98 32' Fever at the end of Sept, with twin rebuilt Merc 502 with 15 hours. Splashed the boat, got about 200 yards from the trailer, started getting on plane, and the port motor alarm went off. Observed the water temp gauge get up to 210 and shut it down.
Before we went out, I showed up to look the boat over, he had his kids out helping him get it ready, and one of them got the weird a$$ Fountain "garden hose shutoff/90 degree valve" fresh water flush backwards, and it burnt up the impeller. No harm no foul at all...I'm still confused by the factory setup...but I digress.
Here's the thing...and this will be a long a$$ question...
I've had the boat out 3 times since I bought it Sept of last year. Every time, the port motor has run hot for a few, no alarm, I shut it down, it immediately goes back to 180 on the gauge (I replaced the thermostat with a 180 ). I've replaced the sending unit, pulled the water neck (found a good sized piece of rubber in there BTW) Ohmed out the wire from the sending unit in the water neck to the gauge, back flushed the impeller housing from the oil cooler, and even felt the risers when it has acted up, and they were normal.
The short story is do water temp gauges go bad that often? Do I have an issue on the drive water pickups? Is there a known ground issue with my particular Fountain?
Yes, this is all quite nebulous, and I'm sory. Jut hoping someon had the same issue.

Take hoses off your oil and power steering coolers and make sure there are no restrictions in them, I run the river and get tiny pebbles in there from time to time. Get a wire coat hanger and run through each tube that is in the coolers, good luck chasing a water restriction can be a pain at times.

Change both impeller housings, they warp very easily from the heat from the impeller running with no water and keep a extra in your boat at all times, remove all hoses and eliminate any impeller pieces. It is important that when you burn up a impeller to count all pieces when you remove it this could be your problem. On your water pick up, see if you can push a l wire to remove any debrea. I have seen on previous boats that a small piece of wood stuck inside this port.

Best of Luck

Just fyi,, you should have 160 thermostats

Thanks! I just replaced what was in there....I'll go down to 160s this weekend....

Also, I have backflushed every hose that I could, forn the thermostat neck down. No blockage. I'll try the water pickups on the drive next. It doesn't have low water pickups, just the upper. Thanks fot the info guys!

The enitire housing was replaced after the inpeller burnt up. And all the pieces came out of the motor, and I backfulhed again just to be sure.

I have had gauges get messed up, had an oil temp one do it, my oil temp would go to 250, stop the motor shut it off, restart, it would be perfect.... It does happen, but so can and do the other things the other members mentioned.

Download the Fountain service manual here. http://www.fountainpowerboats.com/se...er_manuals.asp

It explains the correct sequence to use when flushing the engines.

Yeah, if you're not looking through those coolers to check them, you may be missing something. They are capillary tube style, so water will still flow through but volume can be much lower due to mud, pebbles, etc in the small tubes.

http://i16.photobucket.com/albums/b1...0/5e0a906c.jpg

A length of straightened coat hanger wire works pretty good. I had to soak one of my coolers last year due to mud that had probably been in there much longer than I owned the boat.

Water pressure gauge readings changed completely once that was cleaned out - also water temp readings changed, as well.

I had the same boat and it has 180's in it