This is the place where the majority of the warbird (aircraft that have survived military service) discussions will take place. Specialized forums may be added in the new future
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Wed Apr 23, 2008 7:25 pm

I was on C-124's for 7 years and we never pulled a prop through before engine start. We always used the starter.
The only time we were concerned with a liquid lock was when we installed a new engine, we would do a "Burp Run" to make sure all the "pickling fluid" was out of the new engine. This was a procedure in which we would leave the lower cowling off and take one spark plug from each of the cylinders in #4 row. That's the bottom row for those not familar with the 4360 engine.
Then, we would start the engine, using the starter, and let it run at idle for a minute or so, shut it down, install the spark plugs, cowling and we were good to go.
The first time I ever pulled a prop through by hand was when I started helping out on Ol 927.

Wed Apr 23, 2008 7:55 pm

One thing to remember as well is that most of the manuals were written for airplanes that flew on a daily basis. While hydraulic lock can happen even after a few hours, the longer a plane sits, the more likely it is to occur. As such, in many ways, today it is better to pull a prop through by hand to detect possible hydrualic lock because it's more likely to be present in a major fashion unlike with these aircraft when flying in regular service where typically only a minor hydraulic lock would have time to setup and that could be dealt with by the starter without damaging the engine.
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