Oil catch can return to sump ?
 

I am going to fit a catch can and have an oil return pipe to the sump, where should the sump be drilled to fit the return adaptor ?

Above or below the normal oil level ?

Below the level. That's what I have done for my frontline turbo oil return and will also be the case for the return on p2 aswell

What are the benefits of this? I thought it would be better for the engine to dump the used oil from the can and fit new oil?

If the piping, can and return to sump pipe are all clean, then there's no problem in re-using the condensed oil.
My return pipe goes straight to the sump plug hole via Goodridge fittings.

JohnD

The oil catch can will also collect some water. You wouldn't want that going back to your oil. This thread at Nasioc details what different people found in their catch cans (http://forums.nasioc.com/forums/show....php?t=1387094) , for sure I wouldn't want THAT going back into the oil.

Opinions seem to be mixed about the return to sump ?

A lot of the trackday kits have the return (RCM for example)

I believe that the idea is not just to return oil that has 'condensed' from the crankcase vapour.

In extreme cases, when driven hard, significant quantities of oil can be expelled via the breather pipes on the heads, I would assume this is why the track day kits have the return ?

In very extreme cases yes you wouldnt mind it going back down but under normal use the hot gases that pass up through the breather pipes condensate as they get up and out of the motor and put water in with the oil so i wouldnt have it going back down unless your planning on driving on the track or like a holigan on the road:norty:

Like a hooligan on the road !

Would never consider it mate!

More scaremongering.

What little condensate there is in the oil will soon be burned off and evaporate with the heat of the engine.

If you're not planning on doing track work or drag work then a normal catch can without pumb back will be fine. The purpose of the pumb back is to retun any oil thats forced through the breathers when doing launches and hard cornering. In some cases this has been known to be well over a litre of oil. In those circumstances I'd rather have that going back to the sump over being worried about a little bit of condensate.

Anyone know what fitting I need for the sump and where I can get one ?

RCM do a kit with the hose and adaptor but I think it's about £90 !

Merlin Motorsport will sell the bits for about £10, but you will need to get it welded to the sump.

This
http://www.merlinmotorsport.co.uk/p2...duct_info.html

and this
http://www.merlinmotorsport.co.uk/OI...429/index.html

I do not know about scooby engines, but SBD recommend this mod for the vauxhall engine. This is because the crank breather goes into the cam cover, then another breather from the cam cover to a catch tank, however the oil doesn't drain drain back quick enough, so with proloned high revs you end up with all the oil in the cam cover. You really need to plumb it into the sump at the top or above the level of the oil.

One disavantage to the above is that the engine could be blowing out lots of oil but ou know nothing about. Unless its a common mod for a scooby engine I wouldn't bother.

Cheers Pete !

I wondered whether there was an adaptor that would fit without welding (welding isn't my bag baby !) ?

I suppose the sump wall is too thin to drill and cut any threads, hence the 'boss' for the sump drain plug ?

Opinion on where to fit it in relation to the oil level is also divided, some are saying below the normal oil level, some are saying above.

Any reasons for the difference of opinion ?

I did wonder whether I could utilise one of the sump plugs I have seen that are drilled and threaded for an oil temperature sender, maybe just terminate the drain hose with the correct fitting for the threads ?

Current theory is as follows:

M20 to AN-10 adaptor to replace sump plug

2 x AN-10 90 degree hose fittings (one to the sump adaptor and one to the drain outlet on the catch can)

Appropriate length of braided hose

Fingers crossed for an early result ?

Know what you mean about welding, I know my limits so found a local welding company who charged me £5 to weld the jic on :thumb:.

Regards which level to fit the return, as liquid will only run down hill to me at top of the sump made sense. I can see that using the sump plug is possible and probably the best reason to fit to the bottom. It is also recommended that you fit the catch tank as high as possible.

Just fit a catch tank and keep an eye on how much oil you get, if everything is healthly cant see why you would get too much, especially as you don't appear to have to rev the scooby engines too much as the power tails off!

I'll be doing this on P2 shortly I'll take lots of photos :)

Cool Daz !

Good man yerself !

Im soon going to be making my catch can return to sump, with the fittings to the sump plug as "The Voices" suggested which is simple enough. But if in the future I decide to fit an "Oil cooler kit with oil filter relocation", then will this still be ok. Or will the oil cooler fitting go into the sump plug instead?

Oil cooler install will not require any sump connections, your basically only breaking into the pressure side of the oil system.

Thanks Pal :)

Ahhhhhhhhhhhhh !

Zombie thread !