oil leaking from catch can for drysump tank

[nickmpower]

Well we have a catch can on our drysump tank and it seems to leak oil. The valve on the catch can must be messed up but the point is why is there so much oil going into the can? its vented from the top of the oil tank. the car probably has about 5 miles on it

Edited by nickmpower on Monday 6th August 06:03

[Steve_D]

Think we will need sketches and photos here. Also relative heights of the items and what other breathers the system has.

Steve

[nickmpower]

here are some pics, sorry for the size. In the second pic you can see the breather attached to the dry sump tank, and in the 3rd you can see where the breather has been dripping. It leaked a decent amount. maybe half a square foot after it spread out over a few days

[nickmpower]

it turns out the breather tank was all the way open, instead of all the way closed. But does anyone have any ideas of why this much oil would be getting pushed into the tank?

[Miraz]

You'll get fair bit of hot oil vapour condensing into the breather tank if it has nowhere else to go - usually if you have breather line running from the top of the engine to the d/s tank then the vacuum created by the scavenge pump should ensure that most of the oil vapour is recirculated rather than ending up in the breather tank.

[nickmpower]

yeah thats what i was thinking. Since the scavenge pumps aren't always pumping oil they are sometimes pumping air drawn in through the breathers

[donkeasy]

you don't have to appologise for the size,
it is a joy to look at, the bigger the better...euh

[k wright]

You've got two -12 lines that converge and go into a single -12 line to go through the oil cooler. I think this could lead to a decrease in the amount of scavange ability that the pump has adn may lead to a lot of areation of the oil returned to the tank making it more likely to spray out your breather. If that is a Stock Car Products pump there is an internal manifold that allows you to block off one of the scavange fittings if you fit a -16 fitting to the remaining one. Thereafter a single -16 line can go throught the oil cooler and to the tank.

I plan to use this setup. The other method is to use two -12 lines all the way back to the tank (most likely changing your oil cooler location). You have a Setrab oil cooler. These have fittings that may be upgraded to -16 but if you do this the internal diameter will still be significantly less than the ID of the -16 hose and fittings.

How many return fittings do you have on your dry sump tank and what size are they?

ken

Edited by k wright on Tuesday 14th August 09:16

[nickmpower]

so do most people run their tank vents to the crankcase or to a catch tank?

[Miraz]

Both - I've got a t-piece that splits the breather lines between the rocker covers and the catch tank - that way most oil vapour is recycled through the engine, but you still catch anything that isn't.

[nickmpower]

anyone else?