tetrylone
NAXJA Forum User
- Location
- California
I looked all over the site and couldn't find a problem quite like this one.
When idling this 88 cherokee runs at the normal operating temperature - about 195. But when driving at full speed or especially up hills, it likes to run real hot. Not overheating but real warm, about 220-240. If taken back down to idle, it'll just come down to normal operating temperature. It usually will only hit 240 for a second or two when climbing and then drop down again.
My cooling system is the closed loop but I have an aftermarket aluminum pressure bottle that feeds into a second open loop type reservoir and there isn't an abnormal amount of exchange between the two bottles. In fact, the pressure bottle is always kept completely full and when the system needs to purge or bring in coolant for temperature adjustment, it exchanges through the extra reservoir.
Any ideas here folks? This is really perplexing and troublesome. Why would it run at normal temperature when idling or traveling at slow speeds but want to run hot at highway temps?
When idling this 88 cherokee runs at the normal operating temperature - about 195. But when driving at full speed or especially up hills, it likes to run real hot. Not overheating but real warm, about 220-240. If taken back down to idle, it'll just come down to normal operating temperature. It usually will only hit 240 for a second or two when climbing and then drop down again.
My cooling system is the closed loop but I have an aftermarket aluminum pressure bottle that feeds into a second open loop type reservoir and there isn't an abnormal amount of exchange between the two bottles. In fact, the pressure bottle is always kept completely full and when the system needs to purge or bring in coolant for temperature adjustment, it exchanges through the extra reservoir.
Any ideas here folks? This is really perplexing and troublesome. Why would it run at normal temperature when idling or traveling at slow speeds but want to run hot at highway temps?