Calibrating Water Temp. Guages

[AbunDiga909]

Is anyone's temperature guages not working? I was out yesterday and PP said the water temp. was 64, while CC's guage read it was 54. And, my friends PP, same model as mine, but on his '00 MC, read it was 58 or 60. Not sure what his was but I remember it wasn't the same as mine.

So do these need to be calibrated or anything to get them to be working? I thought CC's was correct but I'm not sure if any are reliable now...

~Austin

[jonbassham]

RE: Calibrating Water Temp. Guages

I have noticed mine is off sometimes too... anyone know how to fix this?

[AbunDiga909]

RE: Calibrating Water Temp. Guages

Another better question may be where in the boat is the reading actually taken? Does PP read it after the water has flown through the heat-exchanger? (ZR6 this is in) That would explain why it reads about 10 degrees more than the boats thermometer.

[1080]

RE: Calibrating Water Temp. Guages

does it really matter what the water temp is.

If it's all about what to wear then stick yer hand in the water.

also air temp, wind and boat speed all have an effect on how cold or warm you keep and your not measuring them!

imo. the temp gauge is a gimmick and not really worth worrying about.

if i'm wrong on this, then a big gold star to you. :???:

[AbunDiga909]

RE: Calibrating Water Temp. Guages

Ummm... ok... thanks... I stick my hand in the water too...

I like to have my guages working...

[Hollywood]

RE: Calibrating Water Temp. Guages

Well they're giving you a reading, I'd call that "working".

[igkya]

"working" may be a relative term. Workin correctly would be more important to me. While I usualyy go woth the 'stick your hand in the water' routine, it'd be nice if the gauge read correctly. Mine seems to read cooler in the summer ans warmer in the off-season. Maybe it does have something to do with location, wind, speed, etc.

[MARTHO]

Water temperature can vary greatly in just a few feet. Any chance the boat's guages are working, just not giving you the reading you want?

[ag4ever]

The other thing to consider is the water temp can change based on water turbulance. Since the water just a couple of feet below the surface can be significantly lower than that at the surface, if you were recently moving some of that water could be pulled up by the prop, and mix with warmer water to give numerous DIFFERENT water temperature within a very small area. So if you have multiple sensor along the bottom of your boat, one could be reading surface temp, one the temp of water two foot below surface, and one a blend of the two.

Therefore, a temeprature gauge should only be used as an indicator of what the temperature range of the water is.

[1080]

maybe if a temperure sensor was attached to the timing magnets, then pp could be programmed to pick up the ambient water temparature at each point as you pass down the course.

[Hollywood]

Or just hang a pool thermometer off the dock... There are just too many variables for a mobile temperature sensor to pick up on a boat.

[Mikeski]

I believe the lake temperature sending unit is incorporated into the paddle wheel assembly. Since these are often in close proximity to the engine they often warm as the engine starts to warm the water around the sensor. See if it makes a difference to read the temps when you are moving. I believe the water temp. feature on my PP works quite well although I have never compared the reading to another temperature gauge.

[AbunDiga909]

I won't be able to test this until April or so. But what got me thinking was that the same exact PP on my friends boat had a totally different reading, that's what made me think it needed to be set or something, because then I'm comparing apples to apples.

[bkhallpass]

Wow, pretty technical.

I usually just stick my toe in the water and calibrate as follows:
- Hot
- Warm
- Cold
- **** cold
:mrgreen:

BKH

[Skidave]

I repair medical equipment for a living and there are two different types of temperature calculation circuits. To make is simple, the reading is based off of a resistance change from the thermal-couple. To calibrate the medical devices, we use specific resistors that equal a specific temperature. I believe the resistors would work in the circuit for the gauges (not the perfect pass). I will have to try next spring when the boat is being used. If someone can find out the type of thermistor used (400 or 700 series), I can get you the exact resistor values for some temperatures.

Also, the thermal-couple for the gauges (not the perfect pass) is located by the raw water pickup. I noticed when you sit for a while with the motor off, the temp goes up because of the engine box getting hot. After a few minutes of running, it stablilizes and gives a steady reading. I never checked it against a real thermometer though...

Dave