Unknown Fluid Reservoir

[macmanks]

I have a fluid reservoir on my 2004 Q located just offset on the driver's side front on the engine near the air cleaner box and radiator. It is a green metal canister and one hose runs from the side/bottom of the reservoir to a portal on the side of the radiator. The fluid is slick/oily in consistency. It is not the power steering, brake fluid, or coolant.

What is it?

thanks!


Modified by macmanks at 11:10 AM 6/24/2009

[maxnix]

Does your car emit a copious quantity of white smoke from the exhaust when you accelerate? Do you know where your coolant expansion tank is located?

Please complete your profile so we can help you better and you don't have to repeatyour car's information in every post.

[macmanks]

No white smoke.

Yes, I know where the coolant expansion tank is located. It is white plastic and contains coolant and is located on the outside fender-wall driver side.

Is there an A/C lubricant reservoir on these cars? Not freon 134A, but rather a compressor lubricant?

[blacksrjdm]

Coolant expansion tank and coolant reservoir tank...two different things. Do these vehicles have a reservoir and an expansion tank, because it sounds like if it is attached to the radiator then you might have both...

[macmanks]

AHA!!!! Perhaps it is the Coolant Expansion tank, never heard of that before

Thank you!

[macmanks]

FOUND IT!!

The tank in question is part of the cooling system. It is the Hydraulic System Reservoir.

Thanks for guiding me in the proper direction. Now to learn what fluid to maintain the level in this reservoir with...

[Q451990]

If you don't have the owners manual handy, you can view/download a copy at http://www.infiniti-techinfo.com under the publications tab at the top of the screen.

I couldn't stand not knowing what this was, so I had to go look it up myself... apparently it's "cooling fan lubricant" and you would use Mercron Dexron III or better ATF. (NOTE: Don't use this in the transmission, only in the power steering and cooling fan lubricant systems)

From looking in the FSM (factory service manual) Nissan used an amazingly complicated belt driven hydraulic pump system to turn the cooling fan. By 2005 it was replaced with an all electric system. I would sure love to hear an engineering explanantion on why one would use hydraulics to drive an engine cooling fan. Seems like they took a lot of effort harnessing energy off of a rotating engine, converting it to hydraulic pressure, only to generate energy to turn the fan again.

I would probably use a turkey baster (or better yet a fluid extractor) and do partial fluid changes on this and your p/s fluid at the same time. I like to do these at each oil change with Mobil 1 ATF, but that may be overkill.

Heath
Modified by Q451990 at 12:08 PM 6/24/2009

[macmanks]

Yeah, I have access to that link from home, but the internet access system at work considers it a download so i am denied access. Yet, it was bugging me not knowing, so I thought I'd pester the excessively intelligent team here

Thank you very much!

Mac

[GThreat]

My guess for the hydraulic design is variable speed capabilities and more flexibility with location. Of course the electric solution offers all that and more efficiency, but this represents an evolutionary step.