Running engine without prop attached

[raven6947]

I have my rigging in the shop and out of boat and getting ready to start up a rebuilt engine. Any reason I can not run it with the rotator attached but without the prop to check total advance on ignition. Thanks in advance.

 

[dieseldog863]

The engine could run warm/hot, because it won’t have the prop pulling air through the radiator.

 

[SWAMPHUNTER45]

You can put a box fan or shop fan up on a milk crate and run it for a bit. Do not romp on the gas, there is no real load on the engine so it is going to whip up fast and that is a great way to spin a bearing.

We do the fan thing all the time, it is not as good as the prop for cooling so you need to watch the gauges at all times.