Mystery Oil Leak (lots of pictures)

vantassell · Post by **vantassell** » 28 Aug 2010, 00:44

I have a pretty bad oil leak somewhere under my hood (my guess is there's actually 2, but one thing at a time). I originally thought is was coming from the gasket on the oil pan, but I don't think that anymore. I finally jacked the car up enough to get all the way under to look and there's lots of oil/gunk above the pan, so that can't be it. I looked at other people's pictures on here and I don't think it's the Turbo Oil Return (at least I think that's what it's called) gasket that a lot of people have had problems with. I think it might be a hose that goes to the radiator and is leaking where it connects to the radiator and the oil is dripping all the way down from there.

If I knew what any of the hoses/lines/dohickeys under my car were called I'd be a lot better at describing what's happening, but luckily I do have a camera to take pictures with.

These first ones are the main leak. It might be easier if I told you where I was to help orient you to what I was trying to take a picture of. I'm laying down with my feet sticking out under the front of the car. Right above my head is the oil pan.

I scooted back (towards the back of the car) about a foot and took these pictures. The turbo oil gasket that other people often have problems with looks more or less clean, but a bunch of stuff to the left of it (that'd be towards the drivers side) is pretty filthy/oily. Any guesses?

This is standing in front of the car facing the windshield, taking a picture towards the passenger side. This hose looks to go from the radiator down to the oil pan.

This one is a hose at the bottom of the radiator (passenger side) that looks like the return/send of the hose in the last picture.

I'm thinking all of this mess is originating from the hose that connects to the radiator right underneath where the thermostat housing > radiator hose is (the big 2" diameter one). It's the highest point I can find with oil gunk on it. I wiped it off tonight and I'll take it for a drive tomorrow to see if any new oil shows up.

Post by **jreed** » 28 Aug 2010, 04:21

The hose beneath the radiator on the passenger side is the transmission fluid return line. If that's where the leak is coming from, I'd remove the metal clip and pull the hose out of it's socket and inspect the o-ring for cracks, splits or other damage.
The o-ring is available here:
http://www.fcpgroton.com/product-exec/p ... ory_id/208
There is also a hose seal, but I haven't replaced that one before. Perhaps somebody else can chime in who has experience with that part.
http://www.fcpgroton.com/product-exec/p ... ory_id/208
Good luck!

vantassell · Post by **vantassell** » 28 Aug 2010, 12:47

Thanks Jreed, now I at least have some words to search for to try to find out more. I hate it when I just don't know what something is called so I don't even know what to look/search for. Thanks

Post by **jreed** » 28 Aug 2010, 14:21

You're welcome. Sorry I couldn't be more specific (I have a '97 855 GLT, so it's not quite the same, although the clamp and o-ring look similar). I'd check the level of the ATF to see if you are low... that might help figure out if the oil is from the engine or the transmission.

Post by **holler1** » 28 Aug 2010, 14:49

jreed wrote:The hose beneath the radiator on the passenger side is the transmission fluid return line.

Check which side you mean. On my 98 V70 AWD the hoses on the passenger side of the radiator are engine oil cooler lines that connect to the oil thermostat under the crank pulley. You can check it by following them underneath the car. These leak sometimes where the metal part joins the hose.

Post by **jblackburn** » 28 Aug 2010, 15:00

The dirty turbo may well be either a clogged PCV system pushing oil past the rear cam seal, or the cam seal itself is blown. It's in a cover just behind the distributor cap, sorta hidden beneath the intercooler hose.

vantassell · Post by **vantassell** » 28 Aug 2010, 16:10

I looked at the pictures of a Oil Cooler Hose on ipd and that's what the hose under the radiator hose looks like. I cleaned it off last night and drove it around today for a bit and don't see much oil leaking from it, so maybe i had just spilled a little coolant on the hose when I was doing something else?

I just recently redid the whole PCV system. I was leaking oil and had white smoke coming out of the dipstick tube, as well as frothy oil on the dipstick itself. Since I replaced it I haven't had white smoke or frothy oil. So I'm thinking the PCV system is ok now, but i've heard it can blow some seals when it is plugged. So maybe I blew a seal before and need to fix it now. I'll try to look for some cover/leaking oily thing behind the distributer cap area. Thanks for the idea!

vantassell · Post by **vantassell** » 31 Aug 2010, 00:05

So after looking at everything more and more I felt like it wasn't any of the hoses connecting to the radiator or anything else I could see. I realized the only way to see where it was coming from was to clean off everything, drive for a little bit, and then see where it was leaking from.

I cleaned what I could with a spray can of 'engine degreaser' and water, then I drove to work and took a look under the hood. There was a lot of oil, a lot more than I expected. I still couldn't see anything conclusive still, I couldn't see the highest spot that the oil was coming from.

Tonight I set about taking off the intake manifold (just like the PCV fix I did a couple months ago) to get a better look. Even with taking off the manifold there's just oil/gunk everywhere. If I had to guess, i'm thinking something to do with the PCV is leaking, but I can't really tell. Now I get to clean off everything behind the manifold, hook it all back up, run it and let it leak, and then take everything back off to take a look. Ugggh. I'm pretty sure that If I ran the engine with the manifold and everything else taken off I'd damage something pretty good.

Anyway, here's some pictures of what I saw when I took off the manifold. I did wipe off some oil/dirt from the top of the clamp of the short stubby PCV hose. It's kind of hard to see in the picture, but the highest spot with oil are the two wires wrapped in plastic going to two plugs/sensors on the engine. I have no idea what the plugs are for, but where they plug into the engine are more or less clean/dry. I think the wires are getting sprayed with oil somehow, so maybe the leak is low, but I can't tell because the oil is spraying up.

: You can see the two wires in a "V" orientation that are the highest thing with oil on them.

: Just another view. It is puzzling that the bottom of the long PCV hose (i think it connects to the PTC nipple?) has oil on the bottom. It might just be the degreaser I sprayed in though. It doesn't look as wet as it would be if it was the source of all the oil.

Anyway, I usually work nights but I have tonight off. So I'll report back in an hour or two when I have everything cleaned off (probably with new pictures so I can take a break from working).

If anyone has any requests of pictures (for their reference) of anything that's usually hidden either behind the manifold/fuel rail/ air box let me know, i'll have it open for a while.

Post by **holler1** » 31 Aug 2010, 06:02

Did the leak start right after you did the PCV? The reason I ask is that I'm wondering if the short stubby hose might have a leak where it attaches to the engine block. That seems to be the area where most of the oil is. You might check it for looseness or a crack. Also, was the block opening where that hose goes clean or might it be clogged?

vantassell · Post by **vantassell** » 31 Aug 2010, 06:07

Got It!!!!

So the moral of the story really should be "Don't over tighten screw type hose clamps"

It was that short stubby PCV hose. I guess I over tightened it when I put it on. Ooops. I guess now I know why Volvo uses those horrible claspy clamps