Talk:Dry sump

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What a great article, concise yet accurate. Well done to all involved. TiHead 08:29, 16 March 2006 (UTC)

Still doesn't say what's "dry" about a dry sump.

-- The article does well explaining most the merits of a dry-sump system but fails to justify the 'decreased parasitic loss' claim since a dry sump system requires additional pumps: one to evacuate the smaller oil pan and another to pump oil from the reservoir. A wet sump system could do with just one pump. Could someone fix or elaborate on this? --Hooperbloob 07:32, 16 May 2007 (UTC)

I believe the parasitic losses refer to the drag on the crankshaft as it pulls through the pool of oil in a wet sump. A dry sump or windage tray reduces this loss. I don't know of a reference, but I doubt the scavenger pumps add as much parasitic loss.--stuston (talk) 23:11, 16 December 2010 (UTC)

In addition to the above, on a road vehicle a wet sump gets additional oil cooling from the air flow around the sump pan itself, whereas a dry sump allows for a separate oil cooler that may be mounted anywhere in the air flow that is convenient. A dry sump therefore allows for more flexible oil cooling arrangements. For this reason a dry sump is/was used for most high performance inline engine applications, such as in aircraft, and in car racing engines such as Formula One and Rallying.

BTW, a 'sump' is the lowest part of a fluid-filled system, in effect where the working fluid drains to, so the bottom of the crankcase is the sump, which is either fluid-filled with oil (wet sump) or empty of oil (dry sump). A wet sump of course cannot be used with an inverted engine, such as the German DB 601 series. A wet sump is simpler and cheaper to manufacture than a dry sump system, usually needing no separate oil cooler radiator, which is why most road vehicle engines use a wet sump.

The other type of oil system is the 'total loss' one, where the oil is used and then expelled from the engine, such as in the old WW I rotary engines, and petroil 2-stroke moped engines and similar.

Gas turbines

This article is entirely focused on the use oaf dry sumps in reciprocating engines. Dry sump lubrication is also found in other applications, most notably gas turbines. The reasons for dry sump lubrication in these applications has more to do with the potential for skidding the bearings in a flooded sump, the high parasitic loses associated with a flooded rolling element bearing at high speeds and the requirement to rapidly remove the oil( which carries the heat) to pass through a cooler to prevent coking (Mrninfinger (talk) 15:34, 5 October 2011 (UTC))

It's a basic truism of WP that any engineering gets reduced to the pages of Hot Rod magazine. If you're in a position to expand this to cover gas turbines, then please do so. Andy Dingley (talk) 15:49, 5 October 2011 (UTC)

Old copyvio material

@Rsjaffe: The section that was copied from Armstrong was added by someone named Drysump back in 2016; I have removed/rewritten it all and cannot find any remaining copyvios from the Armstrong text. Please review if you have the time. Best,  Mr.choppers | ✎  19:01, 14 March 2023 (UTC)