Thermostat?

[spider82matt]

Was driving home from work today in my 82spider. Temp guage started climbing. Got home and put her up on ramps. Upper hose and water pump to thermostat hose hot. Heater hoses to and from heater core hot. Lower hose cold. I,m guessing thermostat stuck closed. Am I on the right track thinking it is the thermostat? Any thoughts would be appreciated. Thanks, Matt

[So Cal Mark]

check for air in the system before condemning the thermostat

[SchaefSpider]

im an air-cooled bug guy, so this water cooling is a little foreign. Would have thought it was mechanical too. Assuiming air is in the line, A. how'd it get there?; B. how do you purge the air?; C. how do you prevent it from coming back? eg. what's the long term fix on this? or is it a work around?

[RRoller123]

Here is the air purge procedure from my manual. Some people (myself included) jack up the front end to get the bleed plug higher and add an incline to the block, etc; but man oh man this is a contentious issue! LOL.

[rlux4]

Once you've gotten the air purged out you shouldn't have to worry about it again unless there's a leak on the suction side of the water pump which would draw air in. The worst two places for air to be trapped in the system is in the heater core and in the bottom radiator hose just below the stat. Filling the system with the heater control valve open takes care of the heater core and drilling a small hole in the stat lets any air that gets trapped behind the closed stat escape:

Ron

[So Cal Mark]

air can enter the system through a leak or leaking head gasket

[spider82matt]

Thanks everyone!! I flushed out the heater core and removed external thermostat. After that, drilled the air hole in the thermostat and rebled the system following burp procedure. Hasn't been above 190 since. Thanks again for all the help.. Matt