Greetings all; long time reader, first post.

We have a 98 S90 (aka 960, right?), 127k miles, have been refilling the coolant reservoir every 600 miles for the past year, finally found the source of the leak while doing an oil change today. From the passenger side of the block is a metal tube which is wrapped in that protective plastic expandable hose/wire wrap. It appears to head under the block to the other side of the car and connects above some kind of subframe which prevents getting a good look. All I know for sure is that the line coming from the block is wet and green. No other wetness under the hood, no puddles under the car, no tell-tale signs of head gasket troubles or pressure problems.

I know an oil pressure switch can leak oil when it goes bad; any chance this is a water pressure or temp switch which is going bad? I'd love to identify this part and know its function and repair/replacement options. If I have to remove a crossmember to complete the job, I'd like to know about it up front before I get into the job!

I've searched the forums and most coolant leaks appear to be coming from old hoses, the plastic radiator inlet/outlet, etc. Haven't seen anything pertaining to this particular quizzical item...anyone have any ideas? I can easily snap a pic if needed. THANKS folks!

 

can you get a pic, might be easier to see what your talking about

 

Sure thing...thanks for the reply :-)

Here's two pics...both from lying under the front end of the car, legs sticking out from under the front bumper, you can see the driver's side (US model, that is) wheel/tire in the background.

Now that I'm looking at these pics, I'm wondering if it's nothing more than a coolant hose with some kind of mounting bracket coming from the block, holding the hose in position?

Any help g-r-e-a-t-l-y appreciated! :-)

 

Hmm...are you sure that you don't have a leak somewhere else that is either dripping on this line or maybe blowing back on it? Reason I ask is that this doesn't look like a tube that actually carries any radiator fluid itself. I can't imagine it would be covered with that plastic tubing if it were. Also, in your pics is looks like you might have some dried fluid on the rubber hoses, which makes me think you might have a leak somewhere else that is being blown back by the fan when the engine is on. Since that ribbed plastic line doesn't get hot, it wouldn't evap as easily there, making it look like that's where the leak is. I would re-check any lines above that area and also in front of the engine and see what you find. Just a thought..

 

Quote from 960 rookie: "...some dried fluid on the rubber hoses, which makes me think you might have a leak somewhere else that is being blown back by the fan when the engine is on. "

Yaknow, I think you're on to something there! I can see how the ribbed plastic bits could allow fluid to reside there, rather than being blown or evaporated away. I shall get it up to normal operating temps and look again. Perhaps a hairline crack or a barely leaky hose is only letting coolant out when up to pressure...I'll do some more checking.

Sincere thanks...sounds like a solid plan!

 

that hose is just engine wiring going to the distribution box on the other side, they're a few coolant lines on that side, i see some evidence of some leaking on the side of the block, but most of it looks old except for the very green bit on your wiring cover

 

Looks like there is some leakage from those 2 oil cooler lines. That indeed is a wiring harness and looks like the coolant is blowing back and catching in the ribs.
I am having similar issues with my 98 V-90 with 158 K on the clock. What I am finding is those factory formed hoses will deteriorate inside where they stretch and connect to hard line. No matter how tight you crank the clamps down after that starts to happen they will seep around the fittings. I have been going nuts trying to stop all of the slight leaks on my V90 and am about to just order a complete set of hoses and just replace everything. I had a heater hose go with out warning a few weeks back and that tipped me on what was happening. I had a leak around the heater control valve that I just could not stop even after replacing the valve. That was until I replaced that hose and wa-la it stopped seeping. I noticed how loose the old hose was on the fitting when I loosened the clamp and then how tightly the new hose fit. That tipped me on what was going on. All the rest of my hoses look and feel ok just like the heater hose did except the very slight seepage at the fittings.