Dry sump vs Wet sump

[Diablos-666]

Can someone explain the difference between the two and the advantages disadvantages of both.

Thanks

[LJTS]

Wiki is good for a basic explanation

http://en.wikipedia.org/wiki/Dry_sump

[Fullmel]

The dry sump engine holds it's oil in a tank there for the actual sump is thiner so the engine can sit lower down lowering the centre of gravity
Hope this makes sense.

[Diablos-666]

How does that differ from wet sump?

[jagracer]

Diablos-666 said:

How does that differ from wet sump?

For wet sump you need a lot of capacity under the engine for the oil so the engine has to sit higher. Another reason for a dry sump is to overcome the problem of oil surge.

[wackojacko]

Diablos-666 said:

How does that differ from wet sump?

A wet Sump holds the oil in situe and picks up from an oil Vain , whereas a dry sump system is pumped through the engine using an Oil Tank and pump which in turn means a thinner Sump overlap/underhang.
Also a Dry sump is more effective on Racecars and serious trackmachinery as it still pumps an even amount of oil to the engine what ever is happening (i.e harsh braking , acceleration or cornering) whereas a wet sump would create an oil surge and dry spot when the Car is being subjected to High G-force on certain axis.


Hope that helps you .....

[Diablos-666]

Yes I think I'm getting there haha

One last question, hopefully!?

If a dry sump using a pump to circulate the oil how does a wet sump circulate it's oil?

Sorry for the noob questions.

[jagracer]

Diablos-666 said:

Yes I think I'm getting there haha

One last question, hopefully!?

If a dry sump using a pump to circulate the oil how does a wet sump circulate it's oil?

Sorry for the noob questions.

With a pump, dry sumps usually use two pumps

[Steve_D]

Wet sump...the oil sits in a sump at the bottom of the engine. The pump sits in the sump. If you corner or brake hard the oil can slosh to one side or end of the sump leaving the pump with nothing to pump round the engine at which point the engine goes bang.

Dry sump...has a small sump and an external oil tank which is normally a tall cylinder. One pump sucks oil out of the engine sump and fills the tank so it does not matter if this pump sucks air from time to time. Another pump takes oil from the bottom of the tank and pumps it into the engine. Because the tank is tall and narrow there will always be oil in the bottom for the engine as there is nowhere for it to slosh.

Steve

[Diablos-666]

Ahhh I get it now, thanks for the lesson

I suppose the disadvantage of a dry sump is the slightly longer delay in getting the oil round the engine due to a pump needing to suck the oil out of the tank and into the sump?

A wet sump would have oil readily available on start up.

[Graham]

Diablos-666 said:

Ahhh I get it now, thanks for the lesson

I suppose the disadvantage of a dry sump is the slightly longer delay in getting the oil round the engine due to a pump needing to suck the oil out of the tank and into the sump?

A wet sump would have oil readily available on start up.

Nope a dry sump system has a tank full of oil somewhere else so the pump is always fully primed, same as if it was picking up from the sump in a wet sump system.

adavantage of a wet sump is its cheap and easy

disadvantage of a wet sump is he space needed for the sump to hold the oil and oil surge problems

dry sump is more complex as you have 1 or more scavenge pumps that suck oil out of the bottom of the engine and one high pressure pump that pumps from the tank to the engine. so more complex and more weight.

advantages are that you can run any oil capacity ( depeends on teh size of the tank) more oil helps with oil cooling. you have a much thinner sump on the engine, and no oil surge as you alwyas have a supply to the high pressure pump.