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Discussion Starter #1 (Edited)
A couple of months ago, I bought a lovely 9-5 2009 Vector Griffin estate with 189ktm on the clock. It had a slight oil leak at what looked like the back of the engine, dribbling onto the sump.

I have driven the car for over 9000km in two months, and the leak has been getting steadily worse.

The seller assured me it was just the oil pressure switch. So I immediately replaced the switch - no joy. The rocker cover gaskets were completely dry, inside and out.
I tried to see where the oil was coming from, but at idle I couldn't see the source and after driving, the oil was all over the place... It was brought to my attention when I took the car in for an oil change about 10 days after I bought it.

So I took off the crankshaft pulley, and although the inside of the pulley was clean, the oil seal looked a bit rough, so I replaced it. No joy. Then I saw a post about needing to take great care with the seals, and letting them rest after installation - which I hadn't done - so I replaced it again, as it was straightforward and I wanted to get a really good look at the giant circlip on the oil pump cover.

No difference - still oil splattered all over the back of the right side of the engine and dribbling down under the sump. But it did seem to be more to the rear than I'd noticed before.

So I decided to have a look at the timing chain tensioner next, that would also give me info about the state of the chain and when I could look forward to that job.

I replaced the two timing chain tensioner seals just before the mandatory technical inspection last Friday, which I promptly failed - due to oil leakage under the sump - 10 minutes and 5km after a full pre-inspection underbody wash! Now I was getting despondent.

So I let the car sit for 20 minutes at idle on axle stands, and revved it to 3000rpm twice for one minute. Aha! A clear dribble straight down from behind the centre of the crankshaft pulley and onto the bottom of the sump. So I theorised: as you drive the car, the airflow pushes the oil back and up, and if enough does leak out to touch the back edge of the pulley, which is rotating clockwise, it also just gets flicked up all over the back of the timing chain cover before it can get onto the inside of the pulley or the poly-v belt. Then when you look with the car stationary, you see oil dribbling back down along the timing chain cover and assume that the source is above - when it was actually below...

So I went and got the biggest inner circlip pliers I could locally - which were only for a max diameter of 60mm... gulp!

With brute force and ignorance, I managed to get the circlip off. Then used a piece of wood and a hammer to bash all around the oil pump cover, which wouldn't budge at first, but after a few minutes it loosened up. I pulled it out with some trepidation, but only a few drops of oil came out, and all the metal surfaces exposed looked pristine, wich made me very happy.

I pulled out the old o-ring, which snapped in my hands - it was so brittle it would not be able to seal anything, so I was glad that the job was worthwhile, even if it did not solve the leak.

Next came the biggest challenge - fitting the circlip back in place. My puny circlip pliers were useless, so I ended up (very carefully) compressing the circlip in a vice until it began to deform sideways, then inserting a piece of 1 or 1.5mm thick steel wire into the holes and twisting the ends together to make a loop of wire. I then carefully released the vice (wear thick gloves and eye protection!) and had a circlip sufficiently compressed that I could insert it into the groove with gentle use of a rubber mallet.

I then cut the steel wire and allowed the circlip to expand. The ends of the wire had to be pulled out with wire cutters (this caused some scratching to the alloy surface of the oil pump cover, but this does not affect the integrity of the seal, nor the pressure applied by the circlip).

Since then, I have driven about 100km and so far, the bottom of the sump, the timing chain cover and the area under the chain tensioner have remained dry (see pics).

IMG_0612.JPG IMG_0642.JPG IMG_0644.JPG

If there is oil on the sump again, it will mean the dreaded leak in that corner where cylinder head gasket and timing chain cover meet - every other possibility has now been excluded, I think...

So to summarise: don't assume that the oil is coming from the top of the engine, even if you see it dribbling down with the vehicle stationary.

Luckily, the Saab is quite easy to maintain so it is straightforward and fairly quick to try out various different things (I may regret these words if it does turn out to be the cylinder head gasket!)

Happy Saabing
Ilya
 

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Discussion Starter #2
Just a quick update - a few hundred kilometres more, and the engine is still dry. I am very pleased, and hope that this will save others time when looking for what seems an intractable oil leak.

IMG_0898[1].JPG IMG_0890[1].JPG

Habby Saabing
Ilya
 

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Discussion Starter #3
Oh-oh... Another 250km, and now there is a little bit of oil on the bottom of the sump (but fortunately much less than before), as well as a "golden streak" on the timing chain cover towards the back of the engine, seemingly coming out of that "dodgy corner" beneath/behind the chain tensioner.

So my next hope is that a cylinder head re-torque might put an end to this, in case it's seepage past the cylinder head gasket. Certainly the CHG appears to be in decent shape otherwise - no oil in cooling water or vice versa, compression consistently good on all 4 cylinders.

As it's a late model (2009) and the valve at the back of the valve cover works fine, I'm assuming it can't be any other part of the PCV system, although I can't figure out how to get a good look at the oil trap to see if it's a leak from that area. There is no obvious pressure blowback from the oil filler tube, at fast idle in any case.

IMG_1010[1].JPG IMG_1018[1].JPG

TBC...
 

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Unfortunately that is where mine was leaking and it was the timing cover. The only way to find it is to power wash the hell out of that area (stick the wand into the hole where you get to the tensioner and blast away) And then to watch.

Hopefully a re-torque will do it for you but on my car it required taking the timing cover off (and to do that taking the engine out)
 

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Discussion Starter #5
I was afraid you might say that...
Just waiting for a good quality torque wrench to arrive, I will keep you posted...
 

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Discussion Starter #6
I was afraid you might say that...
Just waiting for a good quality torque wrench to arrive, I will keep you
Unfortunately that is where mine was leaking and it was the timing cover. The only way to find it is to power wash the hell out of that area (stick the wand into the hole where you get to the tensioner and blast away) And then to watch.

Hopefully a re-torque will do it for you but on my car it required taking the timing cover off (and to do that taking the engine out)
Here’s a picture taken today. Sorry if it’s sideways, I can’t work out how to rotate it on the phone.

6ED4FBCF-E4CD-4FB5-8C9D-04C0ECD88337.jpeg

The really irritating thing is I can’t see this area with the engine running reasonably fast, which is when the oil seems to come out. Is the oil coming from the visible horizontal black seal, or is something further back in the recess leaking? If so, what? That can’t be the timing chain cover back there, surely?

And what about if I tighten that visible bolt on the right a smidgeon?

Questions, questions. Luckily the Swiss auto inspection guys are very laid back, and I have another 7 weeks to sort this out...
 

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In this thread


on about the 4th post down you can see a picture of my engine out of the car from the side. as you can see, right behind the tensioner is where that infamous joint between head/cover/block is and you can see where my car was leaking since that whole area is covered with a film of oil. the oil was coming out of that joint and then running down the ridge behind and under the tensioner onto that flat spot, just like you can see in your photo and then down the timing cover but it was also running down the block under the manifold.

FWIW I went as far as taking the head off and replacing the head gasket but it didn't solve the problem so at that point I knew the engine had to come out. Apparently mine resulted from someone changing the timing chains and guides with the engine in the car at some point (it had a replacement chain on it with the yellow links) so that's probably why it was leaking.

The leak did get worse over time and was eventually really running out of there. If you look in the previous posts on that thread you'll see a video of where it was coming from. But again, cleaning the area up really good will give you a better idea.
 

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Discussion Starter #8
Thank you for the info. I’m not in a position to take the engine out at the moment, and my leak does not appear as severe - for now... I will try everything else first and hope that I can at least get through the tech inspection. It’s not dribbling onto the ground yet...
One other question: What does that vertical bolt (just to the right of the tensioner when looking from the back in your engine picture) connect to what? Does that possibly have a role to play in all this?
 

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Those two bolts attach the front of the head to the timing cover. The head gasket runs all the way up to the front edge of the timing cover and has to be compressed to seal.

Your best shot, at least if it's not leaking like mine was, is to hose it down about a minute before you go for the inspection. IT took mine about 3-4 minutes with the engine running and hot to start dripping at the pan. But my leak was pretty bad (I was leaking about a liter of oil every week) So clean it up, drive it there and shut it off. But if the inspector runs the car a lot you're probably cooked.
 

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Discussion Starter #10
No chance, sadly... We live up a mountain and I need to drive 15 mins to the inspection centre... I’ll just have to take a few heavy-duty tissues with me and dive under the bonnet around the corner from the centre. The leak is much slower than yours, though - I might be losing 50ml a week. I'll keep you posted as to my progress...
Thanks for the info re the bolt.
 

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if you can find a self service car wash near the inspection place then I'd make a stop there before I went to the inspection. yea, they might yell at you once you start but at that point it'll all be over. (mine doesn't yell at me even when I clean the entire engine)
 

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Discussion Starter #12
Just a little update. To prepare for the cylinder head bolt re-torque, I decided to check the PCV system, in case anything needed replacing at the same time. Of course, I immediately broke off the two clips on the main PCV oil trap hose which leads from the valve cover to the oil trap behind the engine. For the last 4 days, I've been driving with reduced crankcase pressure, as the hose is basically completely loose and any gas can escape directly to the atmosphere. And what do you know - the oil leak has practically stopped, see pic.

So I reckon all these things - PCV condition, cylinder head gasket age/condition, cylinder head bolt tension, condition of piston rings (directly impacts blowby) play a role in this leak. I'll be retensioning the bolts tomorrow, and installing the new PCV hoses when they arrive (oil trap hose with clips from valve cover, as well as the breather hose with check valve behind valve cover).

While I'm fiddling around the top of the engine, I will also clean and sand down the head/block/timing chain cover junction area, and apply REINZOSIL 300C to the general area.

I know it's not at all scientific, changing 4 independent variables at the same time and seeing if the dependent variable changes... but hey, I can't draw a 5-dimensional graph, I just want the oil to stop leaking! If the parts don't all arrive in time, it will have to be a staggered experiment in any case...

271192
 

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I often wondered if I could try to draw a vacuum on the crankcase (keep the plugs in, plug up the throttle body, PCV vent, etc) and then put some kind of sealant around that area where the 3-way joint was and allow the sealant to be "sucked in" to the crankcase. Maybe some of that anaerobic sealant so that if it went too far it didn't clog the strainer.

But yea, crankcase pressure would be a cause of this. On mine the PCV was working just fine and in fact it leaked just as much with it disconnected as it did with it connected.
 

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Discussion Starter #14 (Edited)
Well, I managed to re-torque the head today, it was very straightforward. None of the bolts felt noticeably loose. The good news is that the timing gear was very clean, and the timing chain has the yellow links - so the chain and sprockets have been replaced at some point (the engine has done 200000km).

Getting the new valve cover gaskets into place without damaging them was a little tricky, but not too bad.

I've driven about 30km so far, no sign of leaks, but it's early days. Some heavy, high rev mountain driving tomorrow, we'll see then...

The seaslant and new PCV hoses haven't arrived yet. But I did replace the completely rigid and brittle o-ring on the PCV hose to the valve cover so that it is now a tight fit even without the clips.

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Here's the valve cover before starting, just the DI cassette removed.

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Here are the camshafts and valve gear with the cover off

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And the timing sprockets and chain

IMG_1161[1].JPG

The cover is clean - no sludge
 

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Discussion Starter #17
Thanks Unclemiltie, I’m not sure yet... We‘ll see after I’ve done a couple of hundred kms tomorrow...
 

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Discussion Starter #18
As I feared. It seems better, but it's definitely stiill leaking from somewhere. Now it's newer PCV hoses and a sealant job on the outside.
A local Saab specialist here in Villeneuve said that sometimes the polymer composite part of the cylinder head gasket becomes so porous that a re-torque won't help at all - effectively, there is a hole in the gasket. If this is true, surely the material must degrade just as badly, if not worse, around the cylinders, where it is subjected to much greater temperature and pressure differentials..?
Anyway, I can't see any cooloant in oil or oil in coolant problems yet, but I suspect that even a clean and then sealant around the affected area will only be a temporary respite, before the CHG will need to be done.

271235
 

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there could be two problems in this area:
1. there is the oil supply from cylinder block to cylinder head in this area. If you have full pressure on the oil line, some sealing outside might not help, even for very small leakages.
2. there might be some positive pressure in the crankcase which pushes the oil out. Hopefully some sealant will help. It is essential to clean the area.
When there was no pressure in the crankcase due to disconnected PCV and leakage stopped, it might be #2.
Normally there should be no pressure in the crankcase. There is at least one case where PCV System was blocked:

three checks:
1.
disconnect line from cobra
disconnect line from valve cover
open oil dipstick
plug cobra line with your finger, blow into the other line. Air should come out of oil dipstick, most probably you will hear some bubbling in the oil pan.

2.
If you still have the broken line from throttle to PCV, you could try to disconnect the valve and blow into this line. There might be some effort required because inside the PCV there is a small orifice.
Air should vent to oil dipstick.

3.
reconnect everything (or do this first).
remove oil dipstick. Put a rubber glove above oil dipstick holder. start engine. there should be some vacuum contracting the glove.

From the pictures there seems to be some oil around oil dipstick holder, which gives a clue that there might be too much pressure in the crankcase.
 

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Discussion Starter #20
Thanks thaistatos,
I did tests 1 and 3, all good. Test 2 I couldn't do because I couldn't easily pull the clamped hose off the throttle body.

271239


What confuses me after your answer is this: so far, I thought it was the timing chain cover gasket, which I think is just silicone sealant, which is leaking. However, the local Saab chap spoke about the cylinder head gasket being problematic - and now you are also mentioning the high pressure oil supply, which presumably goes through a channel sealed by the cylinder head gasket,

If unclemiltie couldn't solve the problem without pulling the engine and resealing the timing chain cover, it seems that there are two scenarios, one high pressure and one low, which both result in an oil leak at the same place...

The thing that makes me still hope that this is a low pressure problem in my case is that the leak appears to be slow and inconsistent. I'm assuming that an oil line leak would be much more constant, and get worse rapidly.
 
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