Gauge problems
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Lead Driver
Joined: Sep 2004
Posts: 7,208
Likes: 8
From: Wichita, KS
Gauge problems
My 88 BII's dash gauges have some trouble. The coolant temp read high, the fuel gauge goes to full but reads empty when the tank is half full. So I decided to to an aftermarket coolant gauge in it to see wht the temps really are. I recently rebuilt the engine with the help of my son and friends. A new 190 thermostat was installed. New radiator, water pump and fan.
Thing is the after market gauge reads high also. It will hit and show 240 after start up then drop quickly to indicate that the t-stat is opening up. Happens every time.
I came home yesterday and turned the ignition off to kill the engine then back to the on position with the engine not running to check the gauge to see what the temp was. It was about 20 degrees cooler then with the engine running.
Is this the way the after market stuff works? Never noticed that big a drop on anything else I ever owned. Figure maybe the voltage running is what 13.7-14 and voltage not running would be 12. Does seem to make a difference on my gauges in my 94 X. Did I wire it wrong and need to fine another power source?
Seems to me the 20 degree lower reading should be closer is the t-stat working properly. Guess I could have a new t-stat that is opening really high.
Runs 200-220 with out ac according to the after market gauge and 230-240 with ac on. I turn the AC off when it hits 240.
Thing is the after market gauge reads high also. It will hit and show 240 after start up then drop quickly to indicate that the t-stat is opening up. Happens every time.
I came home yesterday and turned the ignition off to kill the engine then back to the on position with the engine not running to check the gauge to see what the temp was. It was about 20 degrees cooler then with the engine running.
Is this the way the after market stuff works? Never noticed that big a drop on anything else I ever owned. Figure maybe the voltage running is what 13.7-14 and voltage not running would be 12. Does seem to make a difference on my gauges in my 94 X. Did I wire it wrong and need to fine another power source?
Seems to me the 20 degree lower reading should be closer is the t-stat working properly. Guess I could have a new t-stat that is opening really high.
Runs 200-220 with out ac according to the after market gauge and 230-240 with ac on. I turn the AC off when it hits 240.
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Joined: Jan 2001
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From: Virginia
I am assuming your aftermarket gauge is electric? If so, did you use thread tape on the threads of the sensor? If you need to seal the threads, use a little bit of sealer sparingly, since it needs to ground through the threads to work correctly if it only has a single wire hook-up.
I would also check the ground strap behind the engine. There should be one running from the bellhousing area up and bolted to the firewall. If you can't find it, you can add one bolted to the engine and then to the firewall, to make sure the cab sheetmetal is grounded properly. Make sure you have a good ground at the gauge itself also.
Did you also put the new gauge sensor in the factory sensor spot? Sometimes people put them different places, and even use tee's which would not give you a accurate reading.
I would also check the ground strap behind the engine. There should be one running from the bellhousing area up and bolted to the firewall. If you can't find it, you can add one bolted to the engine and then to the firewall, to make sure the cab sheetmetal is grounded properly. Make sure you have a good ground at the gauge itself also.
Did you also put the new gauge sensor in the factory sensor spot? Sometimes people put them different places, and even use tee's which would not give you a accurate reading.
Thread Starter
|
Lead Driver
Joined: Sep 2004
Posts: 7,208
Likes: 8
From: Wichita, KS
I am assuming your aftermarket gauge is electric? If so, did you use thread tape on the threads of the sensor? If you need to seal the threads, use a little bit of sealer sparingly, since it needs to ground through the threads to work correctly if it only has a single wire hook-up.
Yup, it's electric. And I think I used thread tape, I'll check. I use two full wraps as a rule and strech it tight. And it is single wire.
I would also check the ground strap behind the engine. There should be one running from the bellhousing area up and bolted to the firewall. If you can't find it, you can add one bolted to the engine and then to the firewall, to make sure the cab sheetmetal is grounded properly. Make sure you have a good ground at the gauge itself also.
The new after market stuff I'm pretty sure I ran to a ground I have going to the battery. I have been wanting to add another ground strap to the frame. Pretty sure the one to the fire wall is there and goes from the back of the upper intake.
Did you also put the new gauge sensor in the factory sensor spot? Sometimes people put them different places, and even use tee's which would not give you a accurate reading.
Yup, it's electric. And I think I used thread tape, I'll check. I use two full wraps as a rule and strech it tight. And it is single wire.
I would also check the ground strap behind the engine. There should be one running from the bellhousing area up and bolted to the firewall. If you can't find it, you can add one bolted to the engine and then to the firewall, to make sure the cab sheetmetal is grounded properly. Make sure you have a good ground at the gauge itself also.
The new after market stuff I'm pretty sure I ran to a ground I have going to the battery. I have been wanting to add another ground strap to the frame. Pretty sure the one to the fire wall is there and goes from the back of the upper intake.
Did you also put the new gauge sensor in the factory sensor spot? Sometimes people put them different places, and even use tee's which would not give you a accurate reading.
On a side note I drove my 94 Explorer today and it does read lower temp Key On Engine Off than it does Key On Engine Running. So that is explained.
I have a guy going to look at it this week to see if the thermostat or gauge is not working properly. It shouldn't go all the way up to 240 to open the t-stat. And maybe replace the AC condenser. It's 22 years old and looks pretty bad. Should improve air flow to the radiator.
