Temperature Gauge issues

[Capt.Ron]

I have a kubota F2560 Mower. Getting ready for the summer I pressure washed it. There was a ton of grass and dirt on top of the drive train under the body and fender cowling. I probably washed out a couple of hundred lbs of crap from under there. Anyway, ever since doing this, the temperature gauge rises to about 1/2 way right after I start it. If I throttle it up it pegs it over to full HOT. I'm positive that the engine isn't really hot and I've tried unplugging from the temperature probe on the engine but it still does it.
I've let it sit and dry for a couple of weeks but it still does it. Any idea what I should look at and for?
Thanks

 

[Nighthawk1169]

Possible water in the temp sending unit shorting to ground replace the sender?

 

[rScotty]

Possible water in the temp sending unit shorting to ground replace the sender?

I agree. With that sort of behaviour from the temp gauge but the motor seems to be running at normal temperature it is usually the sender shorting to ground somehow. Either internally or the wire between sender and gauge is worn somewhere & shorting to ground.

 

[Capt.Ron]

After further review, probably the wiring. It does it with or without being connected to the sender.
Also, if I just turn the key on it will climb to full hot, if I start it, it's showing about 1/2 gauge. Throttling it up it then climbs to full hot.
With or without being connected to the sender.

 

[Roadworthy]

Trace the wiring looking for a bare or worn spot. It may be that in washing the unit you moved the wire a bit causing the bare spot to go to a high resistance short. If it is definitely not the sender and not wire the instrument is the only thing left.

 

[MoKelly]

Did you really get a couple hundred pounds of grass from under the deck and wheel wells? Or were you exaggerating?

I clean my zero turn after each extended use but can’t imagine that much stuff even after a year.

MoKelly

 

[CoyPatton]

I also tend to believe you have a wiring issue. In the old days, before computer controlled everything, the check for the gauge and wiring for temp gauge was to short out the wire to ground. This would cause a functioning system to go to full hot on the gauge.

 

[Capt.Ron]

Did you really get a couple hundred pounds of grass from under the deck and wheel wells? Or were you exaggerating?

I clean my zero turn after each extended use but can’t imagine that much stuff even after a year.

MoKelly

Sadly, yes. I was shocked.
I'm ashamed to say that I never really looked under that seating deck and had no clue that it could hold that much crap. I actually had to go back to my pressure washer 3 times to get it all and the reality is that I didn't. There are still little pockets of hardened grass and dirt under there.
Looking at this pic, I've got a line with arrows. There is what looks to be a small space but it goes all the way across and holds a lot.

 

[WranglerX]

"Most" gauges I have trouble shot or tested seem to follow what is laid out in this document....

https://gilmore-global.com/wp-content/uploads/2019/03/TroubleshootingGuide.pdf