Temperature gauge doesnt register.

[martin846]

Hi
This was my first ride on the bike.
Just come back from a 40 mile pretty gentle run as thick fog.
I noticed the temperature gauge had not lifted off the stop.
The engine does not smell overheated and no sign of any leaks.
The voltage at the sender was just under 3v.
Is it low because the thermostat is stuck open or because the sender is faulty?
Can anyone suggest any tests please before I take it apart?
Thanks
M

 

[dannymax]

It may be stuck....did you try tapping it lightly with a screwdriver handle?

 

[martin846]

Hi
In fact I have done more investigation.
If you short the sender cable to ground the dial goes full scale.
This suggests to me that the sender is defective.

If the thermostat was stuck open, I would think that it would have registered something on the gauge.
I also shorted the fan switch and that works suggesting that it wasn't overheating on the run.
Any ideas the best place for a sender please?
M

 

[Dorney]

Hi
In fact I have done more investigation.
If you short the sender cable to ground the dial goes full scale.
This suggests to me that the sender is defective.

If the thermostat was stuck open, I would think that it would have registered something on the gauge.
I also shorted the fan switch and that works suggesting that it wasn't overheating on the run.
Any ideas the best place for a sender please?
M

partshark.com

Dave

 

[Miles Long]

It may be stuck....did you try tapping it lightly with a screwdriver handle?

I've had this problem for years - sometimes a light tap on the gauge face will get it working, sometimes it starts working on it's own after riding for awhile, sometimes just hitting a bump in the road will correct the problem( which tends to indicate a mechanical sticking issue)
In any event, you can test the operation of the Sender (as well as the Thermoswitch), by removing the units from the manifold and suspending them in a pan of water, then heating the water.
The procedure(s) are outlined in the Clymer manual, pages 344-345.
Testing the Sender involves measuring the resistance, at specific water temps. -
....50c - 153.9 ohms
.....80c - 47.5-56.8 ohms
.....100c - 26.2 - 29.3 ohms
p.s. - a factory or aftermarket service manual will be the best investment you will ever make for your Max!
Cheers, and welcome to the forum!unk:

 

[MaxMidnight]

Check the temperature indicator by:
1. Disconnect the wire from the sender and turn the ignition on.
2. The needle should be on the 'C'.
2. Earth the sender wire the needle should move to the 'H'.
NOTE! Do NOT earth the wire any longer than is necessary otherwise the indicator can be damaged..

If that checks out OK then it is probably the sender, which can be checked as per Mr Long's advice above.

 

[MaxMidnight]

Check the temperature indicator by:
1. Disconnect the wire from the sender and turn the ignition on.
2. The needle should be on the 'C'.
2. Earth the sender wire the needle should move to the 'H'.
NOTE! Do NOT earth the wire any longer than is necessary otherwise the indicator can be damaged..

If that checks out OK then it is probably the sender, which can be checked as per Mr Long's advice above.

 

[martin846]

Thanks for all your help.
When it was hot the sender was 220 ohms,now,cold it's 750.
No wonder it's not registering.
I will order one.
Thanks again.
M