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ejkjell
07-26-2010, 01:55 AM
Equipment is a 2004 Mastercraft Prostar 197. My lake water temperature gauge (not engine temp gauge) on the Speedo is reading 99-104 degrees. I'm located in Washington State, so I know that's not right. Is there a way to calibrate it or what?

Andyg
07-26-2010, 11:30 AM
Equipment is a 2004 Mastercraft Prostar 197. My lake water temperature gauge (not engine temp gauge) on the Speedo is reading 99-104 degrees. I'm located in Washington State, so I know that's not right. Is there a way to calibrate it or what?

From my understanding there is no way to calibrate the water temp gauge. I beleive the water temp is read from the paddle wheel. You may need to replace the paddle wheel to get it to read accurately.

ejkjell
07-26-2010, 11:23 PM
Thanks for the info...What's replacing the paddle wheel like? Expensive? Hard?

deminimis
08-02-2010, 06:29 PM
Just replaced mine. With old paddle wheel, temp read 100+ (can't remember the exact temp, but it meant there was a short to ground, I believe). Replaced the paddle wheel with a new one (same exact thing) and now I get a constant 40 temp reading (has not budged from that reading). I'm mighty frustrated.

93Prostar190
08-02-2010, 06:42 PM
I am interested in this also .... mine seems to be off by 4-5 degrees .... (always stating a warmer temp than is real ...) but my air temp is also off ... any idea where the air temp sensor is located? maybe it is not in a place where cool air can find it.

ejkjell
08-02-2010, 06:50 PM
Mine reads anywhere from 96-105 degrees. This is a feature I don't really need, but it's weird why it seems to read about 20 degrees too high. I'm assuming the paddle wheel is the sensor for the speedos as well? Is there anything else the paddle wheels input information to?

mpm32
08-03-2010, 01:11 PM
Get a pool thermometer, drop it in the lake, if it reads 75 and the temp gauge reads 95 you know it's off by 20 degrees and you'll be able to figure the real temp in the future.

Kevin@MWMC
08-03-2010, 07:08 PM
Just replaced mine. With old paddle wheel, temp read 100+ (can't remember the exact temp, but it meant there was a short to ground, I believe). Replaced the paddle wheel with a new one (same exact thing) and now I get a constant 40 temp reading (has not budged from that reading). I'm mighty frustrated.


Mine is stuck on 40* temp reading too. Don't know why or what to do to fix it..............

WTRSK1R
08-03-2010, 07:54 PM
I could be wrong, but I seem to remember it reading 40 degrees when the paddle wheel is disconnected. It might be something as simple as a corroded connection in the bilge where the paddle wheel connector is.

Good Luck.

Steve K.

deminimis
08-04-2010, 12:40 PM
Does anyone have a clue where the orig paddlewheel transducer line actually ties into the MC wiring harness? I just can't locate it. I discovered the false wall in front of the counsel that gave me access to most everything, but the routing of the transducer wire still escapes me. Thanks!! Its a '04 X-Star.

macattack
08-04-2010, 01:38 PM
Ref stuck at 40 degrees, the 2004 (and my 2005) MC PS owner's manual states:

"Lake temperature is also standard on the gauge.
This comes from the paddle wheel located under the
boat. If the sensor becomes open or shorts-out to
the battery, it will read 32 F. If the sensor is shorted
to ground it will read 150 F. The temperature is also
where the SELF TEST is located. With the lake
temperature displayed, hold down the gauge selection
display button for three seconds or until the
self test has started. During the left test, all the segments
on the display will light up. Also during the
self test, the gauges will re-set, go to mid-scale and
then to full-scale. After two sweeps the system returns
to normal."

You might want to try the self test, but I am doubtful this will change anything; based on the "stuck" indication, the sensor in the paddlewheel is most likely bad; the only fix is to replace the paddlewheel. I replaced mine this past Feb for about $100 and it has worked great...hope this helps, mac

deminimis
08-04-2010, 02:25 PM
Thanks. Mine is a brand new unit, so its not that. I also read somewhere when a person unhooked his paddlewheel, it read 40. So, it does appear a bad connection (somewhere) for us 40-somethings. If only I was having better luck tracing the cable.

Lars
04-20-2011, 08:08 PM
Any luck with this? just got the new boat and it's reading a constant 40 degrees. Interestingly enough, when i turn it to the ACC position (to the left) it reads 120, but with engine running it reads 40. Any further information would be great!

deminimis
04-20-2011, 08:18 PM
After several hours and wasting money on a new unit, I gave up and now just push a kid into the water to see how cold it is.

Lars
04-20-2011, 09:01 PM
After several hours and wasting money on a new unit, I gave up and now just push a kid into the water to see how cold it is.

ha! Love it! as a recent EE graduate, I think I have to try and putz around with this at least for a while.. .maybe once it warms up I'll give it a go. I'll be sure to post back if I get any results.

deminimis
07-20-2011, 05:16 PM
ha! Love it! as a recent EE graduate, I think I have to try and putz around with this at least for a while.. .maybe once it warms up I'll give it a go. I'll be sure to post back if I get any results.

Talk to me Lars. Any luck?

Lars
07-27-2011, 02:33 PM
A bit!

So you have a new paddle wheel? well that's good. Looking at my post here: http://www.mastercraft.com/teamtalk/showpost.php?p=759679&postcount=10

You should find the data sheet. So If you have an ohm meter you should be able to prope the temp sensor on yo ur paddle wheel and it should read aroudn 10.5 kohms, or maybe it was 2-3 kohms? shoot I can't remember. I'm not sure what your paddle wheel looks like, but mine has about 2 feet of cable before the plug. I unplugged it and probed the boat side of the plug with my multimeter. The "hot" for the temp (as referenced in above link) should be about 5-6 volts with key on. If you're not getting that voltage then the boat wiring is suspect. here is what I wrote to Mac attack wheh I was trying to figure it out:

Well I didn't hear back from airmar, but I did do some tinkering and figured a few things out. It's definitely the brown and clear/silver wire that feed the water temp. I think your reading is correct, I'm reading still around 10.5k at room temp. So here's what I did!
I took a 2.2k resistor I had and put it into the socket on the boat side of the plug. with a 2.2 k resistor the boat showed 97 degrees and with a 3.2k resistor it showed 86 degrees. The real question is what voltage should be seen between those two terminals on the boat? Here's where it gets interesting. With the ignition in the ON position I read 5.9 volts, with the engine on I read about 7 and with it in the ACC position I only read 1.9 volts. Your sensor with 2.2k would put room temp at 97 k, and maybe the rest of the difference could be explained by a bad connection. Eh?

I think my problem is a little of both! I'm not too concerned about temp now that it's in the 80s. :cool:

deminimis
07-27-2011, 02:46 PM
Thanks. Mine is definitely in the wiring. I was unable to trace the cable from the wheel to the dash. Any tips with that (the route it takes or???). Thanks!!!

Lars
07-27-2011, 07:24 PM
Not sure either I'd have to look. Let me know if you figure out where it hooks up! just will take a little digging.

musicmd
06-18-2013, 08:53 PM
I'm curious if I have a similar issue. I have a 2004 X-10 - - - in my case, the lake temp is stuck on 95 degrees. I'm wondering if this could be wiring or the sensor itself?

musicmd
07-01-2013, 10:00 AM
Well, yesterday, the temp sensor was working, showing 74-75 degrees (which matches the local reported temps.) Whatever was causing the earlier problem now seems to be gone, at least for now.

deminimis
07-01-2013, 03:32 PM
While doing my stereo install over the weekend, I figured it was time to pull the new transducer wire. Unfortunately, I decided to do this during a heat wave and my metal shop, the side I store the boat in, is not air conditioned. Crammed in the area behind the dash, in that heat, I felt like Cool Hand Luke spending the day in "The Box." Well, despite the heat exhaustion, my efforts were foiled when I discovered the 6 wire plug connector where the transducer cable terminated. So, I need to figure out and find the same connector and then wire it all up (guessing Del City has that style connector). I really think it's the ground wire that has failed with my unit and the temp sender reading suggests that as well. Sure would have liked to check that one off the list since I had the boat all opened up for the stereo install, but oh well. Being of only minimal intelligence, I did not snap a shot of the connector, so trying to find one, based on memory, is, well, challenging. I probably need to go back in "The Box."