fJ60 temp off the charts!

[joey.w]

Hey all- any thoughts on this? This is my 86 fJ60- Driving on the pike yesterday morning down to Oxford...engine temp in fine! I start the truck and get ready to head back and the gauge sky rockets instantly? So I drove back with the heat on and this made no difference? -Belt is fine, fluid level is fine, Water pump is fine, fan clutch seems fine (shouldn't make any diff... on the highway anyway-) so bottom line is as soon as I start the truck it goes into the red but was running normal and cool moments before? Any suggestions ?
JK-

 

[rabid]

temp sensor wire loose? Does it park on hot in a 60?

 

[Michael Hanson]

If the fuel gauge did it too,the fuel gauge needs replacing. MIke

 

[D'Animal]

Make sure the black sound deadening matt that is fastened to the bottom of your hood did not fall down and keep the fan from turning.

 

["N8"]

it went into the red instantly or did it take 60 or so seconds??? possibly a stuck thermostat?

 

[joey.w]

yea, thanks everybody - checking the stat now...(thanks Nate)! I took off the rad cap with a cold engine and antifreeze bubbled up? Air in the line? Fuel gauge is stuck on full-but thats the sending unit ground I think -I'll check the wire just in case. The sound deadening matt is something that would never cross my mind.

 

[nat88toy]

with the engine warm, NOT HOT pop the rad cap and race the engine to about 3 grand if you see bubbles coming up you may have a bad head gasket