Comparison on Temperature gauge

[tomnky]

I have noticed My BX2200 temperature gauge running quite a bit higher than it has in the past.

I have cleaned the radiator, checked the fan belt, coolant level . All these appear to be fine.

When mowing the gauge will go up about half way and not quite that with the deck disengaged. I admit that it could possibly be the thermostat, but I really did not think so .

I then went to the workshop manual and took the wire off the thermo-sensor on the head. put a meter on the lead off the sensor and the other end to chassis just like the manual says to. I then turned on the key and read 7.1 volts potential, the manual states if this reading is less than battery voltage (12 volts) then there is something wrong with either the wiring harness , fuse or gauge.

Is there anyone out there that can take the same reading and let me know what they come up with ?

I honestly suspect it is the gauge itself , but rather than spend $30.00 on a gauge I would like to have a comparison .

The gauge is actually an ammeter that responds to current drawn as the sensor reduces resistance as it gets warmer .

I have taken resistance readings on the sensor and it appears to be good.

Any help in this comparison would be greatly appreciated.

Many Thanks! /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

 

[NY_Yankees_Fan]

</font><font color="blue" class="small">( When mowing the gauge will go up about half way )</font>

My gauge is always about half way when it gets warmed up after about 30 mins or so of hard work, even in the winter when snowblowing. It was above half a few weeks ago and found the radiator was clogged with fine grass, cleaned it now back down to half.

 

[btolle]

I am assuming that the sensor is the last item in the circuit. If that is correct could you check the voltage on the other side of the gauge. If it is battery voltage (probably 13.? volts) then that would tell you the gauge is bad.

If it is not battery voltage then you can start going back through the circuit until you find battery voltage on one side of a connection or item and low voltage on the other side and that tells you where the problem is.

Bill Tolle

 

[tomnky]

Bill,
Thanks for the suggestion . I was hoping for a comparative check, but I guess I will wait until I get over to the Dealership and do some checking on My own.

Many Thanks,
Tom /forums/images/graemlins/grin.gif

 

[tomnky]

Tom,
Just for information : I called the technical reps at Suwanee, Georgia. They concurred on the voltage check being valid, so I tore her down this morning and confirmed it had to be the gauge at a cost of $33.00 from the local dealer and 3 days to get it.

I am kind of glad I did this as I found the nut holding the steering wheel on finger tight(just another case of not paying attention at assembly time). The steering wheel has to come off to get to the back side of the gauge, not really much to it .

I was thinking maybe You should check Yours as it reads like mine did.

I can let You know for sure if this is the cure when the new gauge gets in.

Take Care,
Tom /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

 

[tomnky]

A follow-up: after spending close to $35.00 for a gauge I found out the check in the manual is dead wrong, 6.98 volts with a new gauge. Don't waste Your money relying on that check from the shop manual. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

 

[Volfandt]

I'll read mine tomorrow.
Mine barely registered when I was digging in the winter but it'll run up to nearly halfway at times now in the heat of the summer.
I noticed it would run hotter when I was cutting in some high thick grass but didn't notice the engine working any harder, go figure.
When I keep up with the grass, cutting once a week, it'll run about halfway between a qtr & a half.

Volfandt

 

[Volfandt]

Just knocked off a couple acres and remembered I needed to check something. /forums/images/graemlins/confused.gif /forums/images/graemlins/grin.gif
Seems I can only get my head right whilst in the shower or working my machinery.
It just doesn't take as long to mow anymore...

It's a muggy 92 in the shade and the gauge never reached 1/2 way. It stayed pretty much where I indicated last night.

Anyways, right now with the key on, my temp gauge will move up to the lowest line, a slight deflection. The head is still too warm to keep ones hand on it for over 5 secs or so.

I'm reading 7.1 VDC at the sender's connector. (sender disconnected of course).
Also at this engine temp, the sender to ground is approx 9 Ohms.

I know, the cow's already out but hopefully this info helps.

Volfandt

 

[tomnky]

Volfandt,
Thanks for the comparison, that was exactly what I wanted.

At least now we know the manual is wrong .
I will say this though, when You first put the meter on it will flash battery voltage for maybe a 1/4 of a second, but I never took it to be what they meant.

The new gauge read 149 ohms across the battery post and the signal post.

the thermo sensor as they call it will decrease resistance as the temperature is higher , so it does vary in resistance, the manual gives a table for various readings at different temps. but I don't see how anyone in the field can reproduce those exact conditions.

Thank You again !! At least We learned something from this for future use /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

Tom


Happy Independence Day!

 

[Volfandt]

Glad to help Tom.
For reference with the engine cold the sensor reads about 400 ohms to ground.
I haven't looked at the WSM (I do have one btw) but with these kinds of readings the gauge would have to have resistance built in or there would have to be a large heat dissapateing resistor in series somewhere in the circuit!

Seems some of my neighbors are celebrating alittle early, I just may have to fire up a few retaliatory shots just to keep 'em at bay /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

Volfandt