A friend of mine at work has a pontiac bonneville ssei (supercharged) and asked me the other day what kind of oil does mini use in the supercharger.Of course it must,but I've never seen any mention of which and most importantly,how do you check the level and where do you put it in if it's low.I do remember Peter at M7 talking about douching the oil out of the intercooler with acetone as part of the process in installing the "Device".Presumably this oil has to come from somewhere.??????????????

 

The supercharger is sealed and it doesn't require any oil to be put in or checked. The oil is already in it.

 

so where is all that oil in the intercooler coming from?

 

All that oil comes from the PVC system. If you notice there is a small hose that basically goes from the valve cover back into the intake before the blower. Over time oil will accumulate and go thru the blower via the intake. It is for this reason companies like Alta make catch cans. Most generally sucking oil is bad for performance, good for emissions. I have a catch can on my WRX and empty it about 3 times a year. It is scary how much oil it actually collects. Even scarier to think about all that oil in the intercooler!!!! My Buick Grand National had the same problem. Twice a year, 4 cans of carb cleaner, and hours of labor later to clean it all out..yuk!


T.

 

Yeah the oil catch can is definitely a blessing. What/how do you recommend cleaning the intercooler if oil does get in. I plan on putting a catch can on in a few months and would like to know if I notice anything in my intercooler.

 

Obviously, the oil in the intercooler can't keep accumulating indefinitely. There must be a point at which it reaches equilibrium (ie, when the condensation rate equals the drainage/consumption rate).

Does anyone know how much HP reduction occurs at that point because of the oil?

 

Who says power is reduced from a bit of oil in the IC? Also, the oil that does get into the intake tract is the Positive Crankcase Ventilation (PCV, not PVC!) system which dumps in the vapor at the throttle body.

The M45 is sealed and has an oil supply "for life", which is intended to be about 100k miles.

 

I think 911fan is wondering how the oil coating inside the IC is affecting the intercooler's efficiency.

I believe the same, not sure how much is achieved there, but can't hurt to keep the inside of the IC clean IMO. I clean mine with every oil change.

 

As far as SC oil goes, I think I'm gonna break into mine before 100,000 just to check it out.

Anyone else out there rebuild any SC's yet. Makes me wonder if its more worth it to just buy a brand new one instead. Got to catch one on ebay.

 

From the Miata side of the house...

The Eaton M45 is indeed sealed, and is supposed to be good for 100K.
That said, I've drained/refilled my M45 twice in 45K/ 9 years (hey, I've got lots of cars, and long stories to justify low mileage ) but mostly because it was leaking. Resealed it the last go-'round.
The M45 gear oil is maintained in the front of the SC, and in an OEM car, should indeed be good for 100K.
Getting the M45 out of the car is the biggest deal, draining/refilling is just a matter of a small plug. Definitely not worth getting a new one for the trouble. Actually kind of neat to see all the internals.

 

My gut feel tells me that there should only be a minuscule loss of HP because of oil accumulation in the IC, even at the equilibrium point. So the whole catch can thing is much ado about nothing (as is cleaning out the IC).

But maybe someone has done some objective testing. My gut's been wrong before!

 

Oil coating from the PCV inside the intercooler will reduce the cooling efficency of the intercooler and threoretically the net horsepower via the increased inlet temperature.

That said, i know of quite a few folks on these forums who after installing catch cans on their minis haven't caught any oil yet.--some of this is probably a function of the engine being new and also may be a function of design. i think that as rings wear there is more compression blow by and therefore more positive pressure buildup and there by more vapor and oil escaping--Someone correct me if i am wrong!!

i need a catch can on my SAAB, the intercooler "fills" with oil over time. i have to remove it and dump-and-clean it once in a while. it also has 290,000 miles on it!!

 

The piston ring blow-by is a function of use. When new, lots of blow-by until they break in. After that, very little (almost none) until they start to wear out a long time from now. After that, then blow-by will start to occur more and more.