oil accumulator

[Sirota]

In racing we use an oil accumulator to pre-oil the engine before starting and as protection against temporary oil starvation in high G turns. I've often wondered why you don't see them on homebuilts. Now that I have a homebuilt and can add such things, I thought I'd reach-out to all of you to see if there's a reason (other than weight) not to.

https://www.pegasusautoracing.com/productselection.asp?Product=1249

Thanks,
Dave

[Dana]

I've heard of pre-oilers on aircraft. But you don't need an accumulator for high g turns because unlike in a car where the lateral acceleration throws the oil to the side of the pan, away from the pickup, in a plane in a coordinated turn the oil will still pool in the bottom of the pan or tank.

The inverted oil system in aerobatic aircraft is a whole 'nother thing.

[martymayes]

There is a company called Oilmatic that developed a pre-oiler for a number of GA airplanes. Turn on an electric switch, electric motor circulates oil, oil pressure indicates in the green then you turn the key and start the engine where the oil is already circulating. Very rare to see one installed.

[cwilliamrose]

They have been used in the past on aerobatic airplanes to keep the constant speed prop supplied with oil. I suppose they could bridge the gaps in oil pressure for the engine itself too. I think they may have fallen out of favor in recent years.

[Sirota]

I'm not so concerned about maintaining oil pressure in high G situations as I am to pre-oil the engine before start. Everything I've read suggests most of the engine wear occurs at start-up.

[raytoews]

I have been preaching for yrs.
Guys prime the crap out of the engine and if everything works the way it is supposed to it fires on the second blade,,,,,and usually revs up.
It takes a while for the oil to travel from the pump fill the filter, up to the crank, thru the crank,,,all the way up to the cam and run back to the pan. Cold oil doesn't run as well as hot oil so the cylinders firing are probably slamming against the rod bearings with no oil pressure a few times. They are called pressure bearings because there has to be a film of oil under pressure between the moving parts.
Pre oiler would be good but unnecessary.
Crank the engine over for 15 seconds gets the plugs firing, burn the frost off them, nice fresh air going thru, now throw the fuel in.
If you don't have at least 30 seconds of crank in your battery perhaps you shouldn't go flying?
Radials always do it, at least four blades on top of pulling thru.
It makes me wince when I see these "flying club" pilots start like that.
Stop teaching that.
Think.