Scavenge pump capacity

[krisles]

Does anyone know the capacity of the scavenge pump of the S6 when idling? How many liters per minute can it pump back to the oil tank when idling?

Thank you for your answer.

Kris

[Sagi Badger]

If I am guessing correctly you are thinking of adding an electric pump to provide pressurised oil to the top of the engine...via a spray bar? If so I have tried to find out as well. I have been advised to avoid taking too much oil from the tank...obvious reasons. I thought of increasing the capacity and even controls/sensors to avoid this but being new to dry sumps and being scared of causing damage I have opted for just sitting in the garage looking at the car. I think you can increase the delivery pressure on the feed pump, I have been advised by a race engine builder this is the best option, so your spray bar does not nick too much oil.

If this is not the reason...go on...go on..tell me.

[krisles]

Thanx for a reply. So my answer is yes and no. I will build an additional 0.5 mic filter that will clean oil of all the particles and also condensed water. To do that I use 7.5 L/min electric motor driven pump that is capable to generate up to 50 psi pressure. Part of the flow (about 2,5-3 L/min at max. pressure) will go over the filtering unit back to the oil tank. The rest if the oil I was considering to use as a pre lubrication before cranking the engine and as an additional oil flow for lubrication of engine, especially when idling.

So because the last thing I want is to pump more oil to engine that the scavenge pump can take out I'm trying to find out the flow of the pump when idling.

[astonman]

on my 05 T350 the dry sump tank fills to over full on tickover and then drops to about half full at 2000rpm.I assume it stabilises at this level? But it would sugest that the standard tank is far to small to keep consistant levels at different revs.Does anyone think this could be a reason why they blow up occasionally?

[Sagi Badger]

Over full at tick over? Does it ever get sucked into inlet via the breather hose? How did you discover this, cap off at idle?

[astonman]

yes and yes!

[astonman]

bttt

[krisles]

I decided I will do only the filtration and leave the pre oiling. The tank is very small. Or maybe just build in 2 way electric valve to allow only a few second of pre oiling before the cranking.

[Sagi Badger]

Why not increase the tank capacity? Seems as though it would avoid the oil starvation problem we are perhaps identifying. You would need to keep the pick up from the main tank to avoid air being introduced if you drank too much from either tank and your delivery favoured one over the other, big capacity linking is essential. Safer bet is a complete new tank, twice the size.

[Tuscanuwe]

And how long will it take to warm up all the oil?
It actually took a long while already now!

Uwe

[Sagi Badger]

Like drinking Guiness I guess. Good things worth waiting for? Dont forget the engine mass is being heated as well, if I double my tank capacity I would not alter that. Someone clever could probably do the maths on this.