So I noticed a quarter size amount of oil below the driver's side undertray on the my car (are below where the intake and piping sits). When the car was on the lift, we noticed the HKS air filter (sits in a low position on the HKS gt SC for the G) was covered in oil and there was some dripping. There also was some minor seeping coming from the piping/couplers near the intake/piping.

The only thing that changed recently was that I took my Cosworth plenum off and put back on the oem/md setup. I am running a ARC v2 catch can. There was only a little amount of actual oil in the catch can; the rest was mostly water and vapor.

I did not notice any oil leaking aroung the valve covers. My engine oil is right in the middle of H and L. The oil is clean. Coolant is clean. Fluid levels are good. The car is running fine and strong--no misfiring--no hesitation and no loss of power.

The pcv valve was replaced with a new one in case this was the cause of the blowby. The intake/pipes/maf sensor was cleaned as well. I was told to drive the car for awhile and to monitor oil and check for potential leaks. So far, I have not noticed any signs of leaks, although I have only driven a few hours after pcv replacement.

Has anyone heard of this happening before? I'm hoping it was b/c of a bad pcv valve. Any suggestions/help would be appreciated. thx! btw, about ~24k miles on my 05 g coupe, using Amsoil 5w30.

 

The oil is coming out of the supercharger with the oil detected as dripping from the air filter, correct? Why do you suspect blowby from the engine?

 

ya you wont get engine blowby thru the SC and onto the SC inlet filter.

Hopefully its nothing as you;d be the 1st having to see what HKS repair is like.

 

I originally thought it was supercharger traction oil, and suspected the oil was overfilled when it was "topped off" my last oil change (currently the resevoir is just a tad bit over optimal level. But, the tech told me that the HKS traction oil is green and the oil that was leaking/dripping was yellow. He also said that the small amount of oil in my catch can was the same type that was leaking/dripping--so from this he deduced that the leaking oil was motor oil.

 

Any mesh or something in the catch can to catch the oil blow-by if that is the case?

 

Not sure if the arc v2 ccan has baffling or mesh in it. There would be no way to tell wout cutting into it.

 

Hmm, are u saying it's unlikely or impossible to get engine blow by theought the supercharger and on to the filter?

The tech says the crankshaft pressure might be blowing the oil back and eventually goes to the intake tract.

Could you explain a little more why it's not possible for blowby to occur through the supercharger and on to the filter? Thx.

 

You mean crankcase pressure? There is no route from the crankcase back to the SC except back through the piston rings, combustion chamber, intake valves, manifold, throttle body, to the charge pipe, which is receiving air from the SC. If pressure was going through the PCV valve to manifold, it would still just get sucked back into the motor and out the exhaust. You have a leaky SC seal if there is oil in the air filter. There is just no other way. Your throttle body should have been filled with oil if it was really going against air flow - highly improbable. If you overfilled, perhaps it will work itself out...

 

Per HKS this oil never needs to be changed or even added. If you need to top it off, then it is burning and or leaking somewhere. I have the GT for a 350Z and the filter is higher up in the bay next to the S/C instead of down lower. Never had any blowby, dripping or anything. Just throwing it out there.....good luck.

 

not exactly true. Per HKS you are supposed to check traction oil levels every other oil change. If it is below the optimal mark, you are supposed to follow the procedure on adding a little more oil. Also, you you change your traction oil every 3 years/36k miles per HKS rep.

 

I see...Wow, if I have a leaking SC seal after only ~3k of normal use, that really sukks. My guess is the traction oil was overfilled and I hope this is just where the extra oil got out if it is the traction oil. for there to be a leaky SC seal, I would wonder if the possible overfilling had anything to do with it--But an HKSUSA rep told me there would be no damage to the charger if overfilled, but the oil would make it's way out somehow...there was some oil seeping out of the couplers of the charger piping as well btw...I guess I will just have to drive around for a bit and see if the condition reoccurs and go from there...

 

well....Katsu built my car (mechanic at HKS USA HQ in Los Angeles) and that is what he said. I'll email him and or Mike Quan tomorrow.