quote:Originally posted by 1973 Pantera:
The highest temperature I've seen on an air-cooled cylinder head (Lycoming IO-540) is 450 degrees F. This was on a VERY hot day on climb-out. I would think that air-cooled cylinders would reach much higher temperatures than liquid cooled.
Dupli-Color® Engine Enamel w/ Ceramic Resists temperatures up to 500 degrees F. One would think that if the cylinder-heads reached 800 to 900 F the paint would burn off pretty quickly.
AutoMeter cylinder head gauges for liquid cooled engines top out at 340 F., however, VDO has some that go up to 600 F. for Air Cooled engines.
I just can't see a liquid cooled cylinder head reaching 800-900 F or higher on shutdown.
Agreed. For instance, oil combusts at a lower temperature, and valve stem seals melt (teflon at only 250F). On air-cooled aluminum-head Corvairs, the stock cylinder head temp gauge once showed 510F after a broken fan belt on the road. On teardown a week later, valve seats were beginning to move and the cylinder to barrel register surface had softened & receded, slacking off the head torque so a gasket was ready to blow...