What is acceptable? I am looking at a flathead powered car and the seller tells me on a hot day, it will run about 220 degrees on the highway. Is this too high? Seems it to me. If not on the highway, it runs about 190. Well, if I buy it, I need to drive it home about 800 miles.... any advice? Thanks
Pretty hot. I would like to see a steady 180. Is it very large bore?? Anyway, if it HOLDS 220 with no tendency to go up, it is driveable. Also, if no tendency to escalate, the problem is likely something fixable like timing and not a disaster like a cracked block.
Running hot won't hurt it, as long as it doesn't lose water. Sounds like the rad could be bigger, or maybe the air isn't getting to it good.
If it is a '49-up and has stock distributor, it very likely has inadequate are completely defunct advance, dumping excess combustion heat into the water-jacketed exhaust system.
It is a 1953 engine... The owner in Texas drives it on a daily basis with no problems, just hot day driving on the highway. Oops on the heading typo.....
As an interim fix, put some Water Wetter or Purple Ice in it--should lower the temperature by 10 degrees or so. Just a suggestion.
First thing when you get it home, then, check out actual running advance. This requires trickery...you can't get valid results from a stock '53 by revving it up on the highway, you have to check what is happening under actual road conditions. You will very likely find poor advance operation at road speeds.
Sounds dumb, but check to see if it is actually running that Hot, or if it is just the gauge. I have seen that happen quite often. P.S. those infared (sp) temperature guns don't seem to be all too accurate. Get a conventional thermometer and stick it on the radiator, or tape it to a radiator hose. that should give you a good estimate on the actual temp.
VERY good point...plug in a good mechanical temp gauge even before taking the distributor out to the garbage!
AND pre test ANY new mechanical gauge before installing it by putting it in a pan of boiling water. Cheap or SW or Autometer etc. seen all of them 20 degrees off.
another thing to keep in mind is that it has been FREAKISHLY hot here lately- 22 days of 100 plus last month. Where is the car? there are bunches of Flathead gurus around here I could turn You onto if You wanted it looked at before the Long drive home....
Running a non known flathead for 800 miles at 65 mph is not something I would look forward to. If the system isn't pressurized you may end up loosing coolant at those speeds and overheat. Be sure to also take a bathtub of water with you. Good luck.