1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Hi,

     this is John.

 

I have a 1991 GQ Patrol with Auto. Transmission.

 

In the radiator tank, below the bottom radiator hose, on the drivers's side,

there is a screw-in sender unit, with two wires that go into the wiring loom.

 

I thought it was a water temperature sender,

but both of these wires are broken, and  the temperature guage is still working.

 

Can anybody tell me what this sender unit is for?

 

Thanks in advance,

                                regards,

                                             John.

 

 

 

 

 

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Hi John,

 

My brother had one of these a long time ago with radiator problems (TB42 engine) and I think there was a bottom sensor for coolant temperature that had something to do with an air conditioning cut out when the engine overheated.

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Thank you Viewmont1071.

I couldn't find anything in the Workshop Manual.
so thank you .

I am replying this late because I have been away from ebay for a short while.

Regards,
John.

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

G'day John,

Low water level warning ? 

Just at a guess.

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Hi Kopenhagen5,

                           thanks for the reply.

 

It may be that, not sure what it is for.

 

The water Temp. sender is beside the Thermostat housing,

so there may be two senders for the same thing,

but the temp. guage is working normally.

 

My latest guess was that it may monitor the Trans Fluid temperature.

 

The new radiator had a screw-in plug, wher the old sensor was,

so I have left that where it is till I find out what it is supposed to monitor.

 

I hope somebody can tell me what it is.

 

Thanks again,

                      regards,

                                 John.

 

 

 

 

 

 

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Hi John,

 

My brother had one of these a long time ago with radiator problems (TB42 engine) and I think there was a bottom sensor for coolant temperature that had something to do with an air conditioning cut out when the engine overheated.

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Hi  jiggity-jig,

                  thanks for that info,

I didn't think of that.

 

It would seem like that could be what it is,

as the Temp. guage is working as normal,

and those 2 wires have got to go to somewhere and register something.

 

So, thinking about it, that sounds like it could be what it is.

 

Thanks again,

                 Regards,

                         John.

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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Gday bloke, it's a temperature controlled fan switch.  Controls the electric fans in front of your radiator / AC condenser that turn on when your a/c is activated. AC  essentially is a heat transfer system so to make the interior of the cabin cold it needs to make something else hot (the gas inside the a/c system) This hot gas needs to be cooled so a condensor is installed in front of the engine radiator. The fans are reuired to draw cold air past the fins of the condenser

 

The switch is not critical to engine temperature if you have a radiator fan that is belt driven as the tb42 has  and you do not use the ac

TELL ME AND I WILL FORGET, SHOW ME AND I MAY REMEMBER,, INVOLVE ME AND I WILL UNDERSTAND Confucius 450bc
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Re: 1991 GQ Patrol, what is the sender unit below the bottom radiator hose?

Thank you Viewmont1071.

I couldn't find anything in the Workshop Manual.
so thank you .

I am replying this late because I have been away from ebay for a short while.

Regards,
John.
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