Backwards temp gauge or incorrect sender?

[jpowell86]

I put a new thermostat and temp sender in my 2003 farm pro 2430. Before the new stuff the temp gauge would always go all the over to the right below 40 and stay there no matter how log I ran the tractor. With the new sender in; the gauge is working but appears to work backwards. Any ideas? I've already tried swapping wires on the back and that didn't help.

[greg_g]

Below 40? Are you talking coolant temperature - or oil pressure?

//greg//

[jpowell86]

Below 40? Are you talking coolant temperature - or oil pressure?

//greg//

Definitely coolant temp. With the old sender it would start to left without power. When power was turned on at ignition the needle would go all the way right below 40 Celsius and never move. With the new sender the needle on the gauge starts at the left and comes toward the center as the engine comes to temp.

[Bob Rooks]

40°C is equal to 104°F.

[Bob Rooks]

Definitely coolant temp. With the old sender it would start to left without power. Please clarify. What does that mean?

When power was turned on at key switch the needle would go all the way right below 40 Celsius and never move. Are you saying it pegged the needle?

With the new sender the needle on the gauge starts at the left and comes toward the center as the engine comes to temp. This would be correct. What is the reading on the gauge at that point?

12345

[jpowell86]

Maybe an image will help. That was taken with no power to it.

With the new sender In It starts in the same position when there is power. When it is warming up it goes toward the right.

With the old sender it would be at the left without power and move all the way to the right with power. When the engine was warmed up it never moved.

[Rich Waugh]

Goofiest looking gauge I ever saw. Highest reading is at rest and then it goes to a lower reading, apparently. Looks kinda like they printed the gauge face backwards, doesn't it?

I think that if I was faced with something like that I'd chuck the gauge and sender both and replace them with an aftermarket mechanical gauge I could both understand and believe in.

Rich

[K7LN]

With the new sender In, It starts in the same position when there is power. When it is warming up it goes toward the right.

With the old sender it would be at the left without power and move all the way to the right with power. When the engine was warmed up it never moved.

With the old sender it would start to left without power. When power was turned on at ignition the needle would go all the way right below 40 Celsius and never move. With the new sender the needle on the gauge starts at the left and comes toward the center as the engine comes to temp.

I'd say that the sender was bad and you've got it working OK now. Your operating temperature should be somewhere around 85*C. Disregard the backward movement and the resting spot of 100*C without power. That's common meter operation. The scale is simply reversed and its operation seems to be on par with any working system. To clarify my thinking on this:

1) power off - meter full left

2) power on with cold engine - meter near or past full right

3) power on with engine warming up to temperature - meter moves toward middle (from 40*) as engine warms

4) power on with engine up to operating temperature - meter near 80* midscale

If this is what you observe, you're in good shape! If not, go the mechanical gauge route as suggested.

[jpowell86]

I'd say that the sender was bad and you've got it working OK now. Your operating temperature should be somewhere around 85*C. Disregard the backward movement and the resting spot of 100*C without power. That's common meter operation. The scale is simply reversed and its operation seems to be on par with any working system. To clarify my thinking on this:

1) power off - meter full left

2) power on with cold engine - meter near or past full right

3) power on with engine warming up to temperature - meter moves toward middle (from 40*) as engine warms

4) power on with engine up to operating temperature - meter near 80* midscale

If this is what you observe, you're in good shape! If not, go the mechanical gauge route as suggested.

Currently with the new sensor in the needle starts at 100 cold and moves toward 80 as it is coming to temp.

[Diamondpilot]

Your gauge is backwards of mine on my 284. I think the gauge is printed backwards.

Chris