Temp Gauge
Postmaster
Joined: Nov 2001
Posts: 3,351
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From: Escondido, CA
Temp Gauge
The only thng I can think of without changing your temp sending unit is to do a continuity check on your temp sending unit wire. Hook the positive side to your wire then ground it out. If your gauge/wire is good you will have continuity. If you have no reading look for possible breaks in the wire. If you don't find a broken wire, pull the wire from the back of the gauge and check and do a loop continuity check. Your testing the wire itself for a fault. If no dice that way your gauge is bad or you have a bad ground on the gauge. Hope this helps some.
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Joined: Jan 2008
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Temp Gauge
[updated:LAST EDITED ON 04-Feb-02 AT 07:12 PM (EST)]Here is an easier way.
Have someone touch the connector that goes to the sending unit to a metal part on the engine while you are in the cab turning the key on.
If the connector is touching ground and the key is turned on,the Gauge pins itself to the HIGH side.
That means the gauge and wiring works & the problem is the sending unit.
They are a ONE wire connector BRASS screw in thing & they are near the thermostat housing.
If the sending unit has Teflon tape(white tape) take it off,it doesn't allow the continuity it needs for an accurate reading.
Does your Gas gauge work?
If so the problem isn't the Voltage Reg. on the instrumnet cluster.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
Have someone touch the connector that goes to the sending unit to a metal part on the engine while you are in the cab turning the key on.
If the connector is touching ground and the key is turned on,the Gauge pins itself to the HIGH side.
That means the gauge and wiring works & the problem is the sending unit.
They are a ONE wire connector BRASS screw in thing & they are near the thermostat housing.
If the sending unit has Teflon tape(white tape) take it off,it doesn't allow the continuity it needs for an accurate reading.
Does your Gas gauge work?
If so the problem isn't the Voltage Reg. on the instrumnet cluster.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
New User
Joined: Jan 2008
Posts: 0
Likes: 24
Temp Gauge
What engine do you have?
The sending unit like I said, is near the thermostat housing.
That's the piece that has the Hose from the
top of the radiator going to it.
It is usually BRASS with ONE wire sticking out the top.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
The sending unit like I said, is near the thermostat housing.
That's the piece that has the Hose from the
top of the radiator going to it.
It is usually BRASS with ONE wire sticking out the top.
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
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Postmaster
Joined: Nov 2001
Posts: 3,351
Likes: 1
From: Escondido, CA
Temp Gauge
You know I have never heard of grounding the wire to the block before. Now I know a much easier way. Just to really draw a mental picture of where the sending unit is. It midway between the valve covers on the top of the intake manifold 3-4 inches from the front. Help any?
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Temp Gauge
Excellent news Jevan.
Now Just *Replace the sending unit* and make sure you use the proper sealant on the threads.
Do NOT use teflon tape(it's the white stuff)
Get the proper sealant at an auto parts store.
I'll see if I can find the name of the stuff in the states
It could be a permatex product.
What engine do you have?
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
Now Just *Replace the sending unit* and make sure you use the proper sealant on the threads.
Do NOT use teflon tape(it's the white stuff)
Get the proper sealant at an auto parts store.
I'll see if I can find the name of the stuff in the states
It could be a permatex product.
What engine do you have?
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
Senior User
Joined: Feb 2002
Posts: 258
Likes: 0
From: Allegan Michigan
Temp Gauge
I'm not sure on the 351M but on the 351W the sending unit is just to the left of the oil filter and up a bit.
I f it is not there on the 351M I would start looking towards the back of the block by the intake.
Good Luck
I f it is not there on the 351M I would start looking towards the back of the block by the intake.
Good Luck
Senior User
Joined: Feb 2002
Posts: 258
Likes: 0
From: Allegan Michigan
Temp Gauge
Let me revise that location a bit so not to confuse you with the oil pressure sending unit. The Temp switch is on top of the engine. If you are looking from the drivers side it is to the left of the oil filter (referance point only) and threads into block from the top. Another way to look for it is standing in front of the truck it is just to the right of the distributor.
New User
Joined: Jan 2008
Posts: 0
Likes: 24
Temp Gauge
I'm wondering how he grounded that wire without taking it right off the sending unit.
He never did get back to us.
Dennis https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=1733&.jpg
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
He never did get back to us.
Dennis https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=1733&.jpg
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
