Help me find the source of this leak

[rotorhead]

Any suggestions on what the source of an engine leak like this? I washed the underside of the engine and backed the car into the garage before taking this photo. Pretty significant oil leak!

I am hoping that it is from above the Cylinder and running around the base to appear to come from the cylinder/case join.

What would be the best way to determine its cause... do I have to drop the engine?

[smestas]

Looks like its coming from the cylinder where it meets the case. It could be from a broken head stud. I'm not a profesional but thats what it looks like to me.

Have you pulled the valve covers off and checked the head studs? I had some similar leaking and upon removal of the lower valve cover found a head stud nut floating around with a partial stud in it. If the studs are all intact then you could try to check the torque settings to make sure none are loose.

Just my 2 cents.

[rotorhead]

Thanks Smestas...

picking up a socket wrench now to pull off the valve cover and I'll let you know what I find.

[rotorhead]

Good news... I think

Took the lower valve cover off and checked the head studs. They all hold torque.

I guess that I'll have to try and get at the top of the engine to see if the leak is above the cylinder.

[Wayne 962]

Cylinder base gasket. These 2.7 engine cases warp and then leak at this interface. This is why you need to have the cylinder bases machined when you recondition the case. It's very common to see this on these engines. Check the top of course - there's plenty in this area that can leak. However, if the top is dry, you'll have to live with the leak until you rebuild...

-Wayne

[rotorhead]

Thanks Wayne

Its a 3.3ltr Turbo. I am going to have to fix this before I can get a roadworthy certificate for registering the vehicle.

I guess the nest step is to check above the cylinder then drop the engine.

PS I have both your books and eagerly await the third for my BMW.

[copper]

Run a flouresced additive and use a blacklight. this will help to trace the problem and seperate old oil leaks from the new ones.

Jim

[rotorhead]

I think this is very good news I removed the air box and this is what I found at the front of the engine. Looks like a leak from a crankcase breather hose (I think).

Could this be the source of what is running down the front right side of the case and dripping the the base of the cylinder?




On page 64/65 of 101 Projects this type of leak is explained. Do you think that it would leak this much from a crankcase breather hose? Or should I keep looking..

[911pcars]

The area around the base of the breather cover does look a little oily doesn't it? I notice the hose clamp for the oil tank hose is still in place. Is that hose material I see still under it? Was the hose torn or is that just an optical illusion? There's a lot of oil slung up in this area. If the hose was torn, this could be a source for the leak below.

I was going to suggest the oil pressure sending unit (also shown in your pic), but it looks dry.

Sherwood

[rotorhead]

The clamps are still in place and the hose has not come adrift but it appears to be leaking quite significantly.

Tomorrow I am going to clean it up, replace the hose and clamps and give it a run. It could be the breather cover gasket but with all this sludge it is tough to tell. I am still sceptical that the large leak shown in my first image is all from this source.

[cmonref]

Maybe a leaky through-bolt? The acorn nut is right where that oil comes running out from under that darkest piece of sheetmetal. The through-bolts are part of the oil galleries holding oil pressure. If the nut is loose, the seal will not hold the pressure back.

[rotorhead]

I cleaned it up and undid the clamp and the hose slipped off the breather tube.

Do you think this might be the problem?

[911pcars]

Steve,
I'm not familiar with how the factory 930 breather hose fits onto the crankcase breather pipe. It looks like you could delete the cap and use another hose clamp to secure the rigid pipe onto the short length of flex hose.

Sherwood

[OZCarrera3]

Hi Steve, is that really a factory fitting? How does the collar attach the hose the pipe? Is the collar just an aesthetic item?

I agree with Sherwood, replace the collar with another hose clamp.

[mede8er]

While your in there replace those deck lid struts and lose that white stick......

[rotorhead]

I double clamped the crankcase breather hose. I appears that this was a pressed fitting which came attached to the steel return line. It doesn't leak now



But the leak still persists from the base of the #6 cylinder. I moved the sheet metal a bit to get a better look and it appears that the copper gasket is protruding from the join. I think that this leak can only be fixed by dropping the engine and replacing this gasket.

[OZCarrera3]

Unfortunately yes, there's no way to replace that without pulling her down. Sorry to hear that Steve.

[rotorhead]

Thanks Sheldon.... trouble with removing the P+C is the extra "while youre in there" work that must be done like ARP/Raceware head studs + rod bolts, valve guides, SC cams, valve seats....... I will have to put a realistic estimate together and then put together the cash.

I guess I will have to live with it for a little while. It leaks about 2 drops per hour.

Do you guys think that the vehicle can still be driven?

[OZCarrera3]

Yeah, but there's nothing like the feel of a new, strong, quiet and DRY motor!

As long as the oil level is still above minimum, I don't think you can do any harm, but I think Qld Transport may take a dim view of the oil leaks. That said, mine was dropping a lot more before I rebuilt it.

Seeing as I have just been throught htis whole ordeal, I'm happy to share my experiences, prices paid for parts and supplier contacts if you want, just drop me a PM.

Good luck!

[dickster]

i have a similar leak (for some time now) on my 3.2. i think mine is from the oil cooler and have the o rings ready to install...one day.