1310 Temp Sending Unit

[kc5sii]

My temp light doesn't come on when the ignition is switched on. If I short the lead going into the sending unit, the light will illuminate. Is that normal or is the sending unit likely bad?

 

[JC-jetro]

My temp light doesn't come on when the ignition is switched on. If I short the lead going into the sending unit, the light will illuminate. Is that normal or is the sending unit likely bad?

Are you looking at temp unit of engine oil sending unit? Do you not have analog temp gage? or you have both?

JC,


Sending unit is a variable resistance element, If I short out mine the needle will peg to max temp. Oil sending unit is a normally closed switch that oil pressure will open up, so key in (turned ) oil light comes on, proving the circuit and engine on the light goes out due to oil pressure.

 

[kc5sii]

I'm certain it´s the sending unit on the Left side of the motor. The Oil sending unit is on the right (Facing Forward) and the temp switch is on the left. The tractor is only equipped with an "idiot light." The sending unit is an open circuit. I don't know if it's supposed to be closed or open when the tractor is cold but I would think the light would come on when you turn the ignition on for testing purposes. Maybe not.

I guess I can pull the unit and hold a Bic lighter under it to see if it turns the light on.

Are you looking at temp unit of engine oil sending unit? Do you not have analog temp gage? or you have both?

JC,


Sending unit is a variable resistance element, If I short out mine the needle will peg to max temp. Oil sending unit is a normally closed switch that oil pressure will open up, so key in (turned ) oil light comes on, proving the circuit and engine on the light goes out due to oil pressure.

 

[JC-jetro]

I'm certain itｴs the sending unit on the Left side of the motor. The Oil sending unit is on the right (Facing Forward) and the temp switch is on the left. The tractor is only equipped with an "idiot light." The sending unit is an open circuit. I don't know if it's supposed to be closed or open when the tractor is cold but I would think the light would come on when you turn the ignition on for testing purposes. Maybe not.

I guess I can pull the unit and hold a Bic lighter under it to see if it turns the light on.

I it is "idiot light", then it is normally open and heat (excessive) will close the contact against a spring causing the light to come on. Bic Lighter or better heat gun will let you know in 10 seconds.

JC,

 

[kc5sii]

Then I'll bet it is working right. You would think with the ingnition on without the engine running would put it in the "test mode" like a car does. Not so apprentley.

I pulled the instrument pannel apart earlier and I think I got the warning lights confused. I had an intermitent alternator light. I'll bet it was actually the temp light. I need to figure out something on keeping antifreeze in the system. Maybe the radiator is clogged.

 

[JC-jetro]

Then I'll bet it is working right. You would think with the ingnition on without the engine running would put it in the "test mode" like a car does. Not so apprentley.

I pulled the instrument pannel apart earlier and I think I got the warning lights confused. I had an intermitent alternator light. I'll bet it was actually the temp light. I need to figure out something on keeping antifreeze in the system. Maybe the radiator is clogged.

That is the problem since you can establish if the circuit is good, a broken circuit and you might not be able to find Over heat before it is too late. I'll be looking at 1310 circuit on my IT to see if it is like I said. I'll do the heating the sender unit if it does not dump a whole bunch of anti freeze. After few minute of operation the T-stat should be open enough to see flow in the radiator by removing the cap and take a look. Of course, This test is not recommended on a hot engine due to the obvious reasons.

Jc,

FYI

 

[kc5sii]

It does circulate coolant. It pukes it out slowly and needs filled about every other use. I'm suspicious of the head gasket but can't really see any other indication that a gasket is a problem. Maybe a plugged radiator?

It runs fine and smokes a little white smoke when first starting but clears up and runs clean very quickly.

The main thing is that I know if it´s getting hot before it´s too late. I have an old automotive temp gauge that I might install temporarily to see if I can get a better idea what´s going on.

Dave

 

[JC-jetro]

It does circulate coolant. It pukes it out slowly and needs filled about every other use. I'm suspicious of the head gasket but can't really see any other indication that a gasket is a problem. Maybe a plugged radiator?

It runs fine and smokes a little white smoke when first starting but clears up and runs clean very quickly.

The main thing is that I know if itｴs getting hot before itｴs too late. I have an old automotive temp gauge that I might install temporarily to see if I can get a better idea whatｴs going on.

Dave

Dave,

Hmm , white smoke aye, that's indicative of burning anti-freeze in the combustion chamber thru crack head, cylinder wall or head gasket. Do you see any sign of antifreeze in the oil? do you see tell tale sign at upper and lower hoses both at the engine and the radiator? how about the weep hole at the water pump?

JC,

 

[kc5sii]

I've been intending to get by the parts store and get a test kit to determine if there is any oil in the coolant. There is none visible in the water.

I've had the hoses off and flushed the system as best I could with a hose and really didn't notice anything abnormal.

If I had water seeping into the head wouldn't that cause compression problems? I guess if it was only a little water it might not pose as much of a problem.

Good idea to check the weep hole in the water pump. Is it on the bottom of the pump? That would be an easy fix.

 

[JC-jetro]

I've been intending to get by the parts store and get a test kit to determine if there is any oil in the coolant. There is none visible in the water.

I've had the hoses off and flushed the system as best I could with a hose and really didn't notice anything abnormal.

If I had water seeping into the head wouldn't that cause compression problems? I guess if it was only a little water it might not pose as much of a problem.

Good idea to check the weep hole in the water pump. Is it on the bottom of the pump? That would be an easy fix.

I think the compression issue in case of small leak would be beyond accurate compression measurement to diagnose the problem with certainty. A crack in the gasket can cause a bit of seepage without having any issues with the head or block. Expansion of metal parts after engine warming up might just seal the weepage while engine is operating temp. The weep holes that I have seen is downstream of the shaft seal with the weep hole on the bottom to get a quick visual of seal failure. I'd look for calcification tell tale sign right at the weep hole. If you fill the radiator too much and your radiator cap spring and seal lip is not good you might use liquid without even knowing it. I'd suggest you make a home made collection device like I have made using a jar of used p.butter and some rubber hose for visual clue.

JC,