JG1966
Well-Known Member
My 340 72 RR is running hot after about 10 minutes on the road. Right around 210-220 (Stock gauge goes to a little before first "hot" line). It stays cool when it's idling forever but as soon as I get on the road, it starts to creep up. Timing is right and not running lean. Switched from 160 to 180 thermostat. That helped a little. I suspected 26 inch radiator might be clogged (it doesn't seem to flow very well when I ran with cap off). But wouldn't it get hot at idle if radiator was clogged? I have 18 inch flex fan with shroud, non ac water pump and pulleys. I do have a 3000 stall and wonder if that may be causing my heat (using both radiator and separate tranny cooler). From reading on this site (lots of overheating issues with Ma), I know it could be a dozen or more things causing to run hot (and spit coolant). But does fact it stays cool at idle eliminate or point to something? Thanks
Last edited: