Hey Guys,

I have a 1989 F250, with the 460bb, and my temperature gauge never reaches the "Normal" threshold...It moves up about half an inch..

I never tow or haul more than 800lbs, so I was wondering if this is normal because of the heavy duty heating sytem, or something wasnt right.


Thanks

 

The thermostat is supposed to keep your coolant at 193*.
Having a "heavy duty" cooling system is not going to make a bit of difference.

If the engine never reaches operating temperature the computer is going to run in closed loop constantly.
Do you have access to a non-contact digital infrared thermometer?

If the engine is cold (in the morning) open the radiator cap and start the engine.
If the thermostat is missing or stuck open you will see the coolant flowing across the top of the radiator.

 

i just changed the thermostat,

could it be the temp sensor? could it only work at certain temperatures?

 

Could just be a bad ground.
Pull the wire off and ground it to the block.
The needle should be pegged then.

 

My signature vehicle was acting like that from when I bought it. Finally got around to checking t-stat, PO had put t-stat in backwards . Might check that. This must be fairly common as my previous truck ('90 F150 5.0 XLT) was also that way.

 

Factory gauges in these trucks are notorious for being inaccurate. As Ard said, see if you can rent/borrow/beg/steal (well not steal) an IR thermometer and check it. Then consider adding a set of good aftermarket gauges.

 

Mine was $18 and reads -58 to 1.382*F.
I see it's up to all of $22 now!!!

Just shoot the water neck (thermostat housing) when it's up to temperature.

IR thermometers are great diagnostic tools.
Dead cylinder? which exhaust port is coolest?
Can't find the draft in your house?
Kid got a fever?
Surface temp of anything, actually....

 

Reminds me when I used to run at the drags, lick a finger and touch the headers at each cylinder to find that miss.