PPRuNe Forums - View Single Post - Shear Section In The Drive Shaft Gearbox Component???
Old 7th April 2006 | 04:44
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Bolty McBolt
 
Joined: Jul 2005
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From: OZ
Engines have a min temp at which the engine my be cranked which is related to oil type brand etc eg Exxon 2380 has a lower pour point than Mobil jet 2.

If the engine is cranked at a temp below the Min temp there is a very good chance that one of the following things will happen

1. The oil pump input shaft will shear due to over load and the shaft bearings will receive insufficient lube as the engine comes up to speed.
2. The oil will be too thick and the bearings will receive insufficient lube as the engine comes up to speed.


APUs have de-oil solenoids that allow a cold soaked engine to start....... Large turbo fans do not

Last edited by Bolty McBolt; 12th April 2006 at 10:20.
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