View Full Version : Normal operating temp?

04-21-2008, 06:45 PM
Just wondering what temps these air cooled machines run at in say 90 degree heat.

Sump temp

Also what temps do the water cooled engines run at?

04-21-2008, 10:05 PM
It took me a while to dig this back up from 2006 but gives a idea of what they run, I never performed the test on a water cooled engine.

Test engine; Kohler CV25S Spec. # 69511 Freshly Tuned and Serviced With 828 Hours, Mounted on Sears Garden Tractor With Hood Removed To Simulate Open Cockpit ZTR
Test Equipment; Raytek Raynger ST Non Contact Thermometer
Chepo Walmart Stop Watch

Areas Tested; Center of # 1 & # 2 Valve Covers.
Rear Center of Engine Block.
Center of Muffler.

Test Went as Follows;
Cold Start-Up and Idled 1155 RPM For 30 Minutes.

#1 V.C. 158 Degrees ---#2 V.C. 155 ---Block 192 ---Muffler 480

Engine At Full Throttle 3700 RPM No Load For 30 Minutes.

#1 V.C. 160 ---#2 V.C. 158 ---Block 198 ---Muffler 462

Engine Back At Idle 1155 RPM For 4 Minutes.

#1 V.C. 146---#2 V.C. 142 ---Block 190 ---Muffler 396

The full throttle Temperature most likely would have been a little higher had the engine been under load mowing but I could not perform that test.