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Saab Mad
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Discussion Starter · #1 · (Edited)
A couple of weekends I dropped the sump from my 9-5 Aero. The engine had been sounding increasingly rough, especially recently. I hadn't got around to dropping the sump since I bought the car in April - a near fatal mistake.

Sump as removed from the car with the top baffle in place.


Baffle and pick-up tube removed. Look at the top-left of the sump pan.


The shiny metal bits would be white metal and copper from number 3 main bearing.


Not much sludge at all on the strainer but there is swarf.


Sump cleaned and oil strainer fitted with new o-ring.


Now to work on the big-end and main bearings.

As an aside, when you do the sump drop, make sure to remove the oil pump pipe you see toward the right of this photo. The o-rings harden with age and leak.


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Saab Mad
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Discussion Starter · #2 ·
All main bearing caps and shells removed. All bearings were good except number 3.




Number 3. Out of focus but you can still see copper from the bearing. The journal was slightly scored.


Main caps and the old bearings.


A new bearing pressed into a main bearing cap. You can see the old crank thrust washers.


The main bearings. They're not in any order except for the number 3 pair at top-left.


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Saab Mad
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Discussion Starter · #3 ·
On number 3 there is no white metal or copper left on one side and on the remaining shell surface there is only patchy copper. The underside of one shell is blackened by heat on one side.

Big-end bearings.


Big-end bearings were also replaced (no photos of that though - too busy!).

I'd recommend checking the condition of the big-end and main bearings when the sump's dropped. Doing that work without a lift would be difficult; it was made much easier in this case for me because I had access to a lift.

So a lucky escape for my car's engine. The bearing's days were clearly numbered and could have seized and spun at any time. Martin said the bearings were in the worst condition he'd seen on any engine which had escaped a spun bearing.

Depending on number 3 main journal, the new bearing may wear prematurely and spin afterall. Just have to wait and see. In a year I may drop the sump again to check.

The new bearings were run in (reduced boost and engine speed less than 3000RPM) for 1000 with an oil and filter change at 500 miles. I also fitted the PCV kit update and new spark plugs.

The engine sounds very much quieter and smoother and the increasingly bad pinking problem (any ambient temperature, driving style or fuel type) has now gone. I suspect a PCV system fault had been drawing oil into the inlet stream, thus lowering the fuel's effective resistance to detonation.

Thanks again to Martin Bayfield for his help (and patience!).

Eight lives left for the engine :eek:

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Thats some scary stuff! How has the car been looked after and what k's/miles is it at? Good to see its all back together again.
 

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And on an Aero too, well done Matthew and .................wake up everyone :eek:
 

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Saab Mad
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Discussion Starter · #7 · (Edited)
Car was bought by me in April with 88,500 miles on the clock and full main dealer service history with 12,000 mile oil + filter changes.

I switched to 6,000 mile oil + filter changes.

Car had 104,500 miles on the clock at the time the photos were taken. Current mileage is now about 106,000 miles.

The damage to the bearing is my own idiot fault for not doing this work earlier. Had I dropped the sump in April I would have found that no. 3 main bearing was in much much better condition, with perhaps no damage to the journal.

That said, the strainer had little sludge on it so the bearing damage must have a different cause. The engine has always used oil and I have been guilty of not checking the levels frequently enough. For now I'm attributing the oil consumption to a clogged PCV system (and resultant pinking).

Still doesn't explain why no. 3 is so bad yet the other mains are almost unworn. In fact, one main pair shows no wear at all.

Why is no. 3 trashed yet the others are fine?

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Matthew, that is same car as mine, with same service history and roughly same mileage, AND i started doing 4-5k fully syn oil/filter changes from 58k onwards, 2 years ago........Im going to poke around with a coat hanger next oil change to 'fish for sludge'):eek:

Matthew, when you say burning oil, how much exactly? Ive had to top mine up here and there, in between every 5k oil change i top up about 1/4 litre:eek:

Was yours more or less???

And after an oil change, how soon did your oil normally turn black??

Sorry for all the questions, but those pics really worried me! The only comfort i got is that the screen was not dramatically clogged:eek: (fantastic write up by the way) -
 

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Saab Mad
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Discussion Starter · #10 · (Edited)
The oil consumption varied. I wasn't sure what caused the variation but it could have been driving style with less oil being consumed on a motorway journey compared to A and B road thrashing.

I have known the engine drink a litre of oil in 1000 miles and on other occasions it's not used a drop.

The engine oil on turbocharged cars I have owned turns black very quickly - sometimes within 100 miles. That's something I've known on all the turbocharged cars I've owned.

The rate at which the oil blackens depends on driving style. Driving the car hard will cause the oil to blacken quicker due to the heat. If your driving style is more gentle then the oil may stay pale for many miles.

A friend of mine said the oil on his car stayed "looking like honey" between oil changes - a feat I never have managed to replicate. No coincidence that he drove sedately.

Blackening seems to be independent of brand too - Mobil 1 0w/40, Valvoline 5w/30 and 5w/40, Halfords 5w/40 have all blackened and on different model Saabs.

I don't think blackened oil is a problem with synthetic (which we all run, don't we?).

If you haven't yet dropped the sump on your Aero Mike, then I suggest you do so. You can DIY or pay someone, just don't put the job off like I stupidly did.

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Thanks for a quick reply Matthew! My oil is still pale after 3k since August, fully syn 5w 40 halfords brand. I quite possibly drive sedately:eek:

I have noticed the same with oil consumption, not sure under what circumstances it burns etc - but I have come to the conclusion that all cars use oil here and there. It may burn it when it gets very hot and high revs - may try the 5w 50 and monitor it.

On a turbo'd car such as ours, I would have expected my oil to go black very quickly. I think I have the original PCV kit (no outlet on filler tube).;oops:

Dropping sump will def be done by a garage, I aint risking doing that job at the side of the road outside my house!! But I will wait until the new year and will take pics etc.
 

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Saab Mad
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Discussion Starter · #12 ·
Not all garages will take the time to check the engine bearings when the sump's off. I recommend you find somewhere that will. If the bearings are fine then you have peace of mind from knowing the engine's healthy; if not then you get the chance to repair any damage by re-shelling.

A set of shells are dirt cheap at about £70 inc VAT. Fitting would be around two hours labour.

Given the small cost of the work, I'd be tempted to get the shells replaced anyway. I know that one thing can lead to another but new engines aren't cheap and this is good preventive maintenance.

If you get the shells replaced then remember the 1000 mile run-in with oil + filter change at 500 miles.

Make sure that all rubber o-ring seals are replaced. The current seals will be hard and won't seal properly when parts are refitted. Get that oil-pump pipe o-rings replaced.

There is a least one hose that's part of the PCV system but not included in the kit but which must be replaced anyway. It's sort of L-shaped and fits between the oil catch can and the sump.

Definitely have the latest PCV kit fitted too.

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Yep, it can happen to anyone. Interestingly, your pan looked worse than mine. Yet, my strainer had about the same amount of junk it it. And...my crank area had a nice goopy coating.....
 

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ok thanks!
 

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Thanks for the great write-up. Echoing everyone else this scares me. I have 177K miles on my 2000 9-5. Dropped the pan (a while ago) and found similar screen blockage to you. Now I want to replace my bearings! :eek:
 

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Just remember that this engine was maintained at 12k intervals for almost 90k miles. So it had what, like 7 oil changes? At 6k miles, with that teensy filter they use, I think hardly any filtration is occurring...
 

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oil pump pipe o-ring part number

I'm getting ready to change all of the bearing in my 2001 9-5 2.3t. Is there a list of recommended parts to replace while I'm down there. I was planning on main bearings, rod bearings, oil pick up o-ring, and the oil pipe o-rings...anything else????

Also, where can I get the o-rings for the oil pump pipe referenced above. Does stateofnine.com sell them???? They have the oil pick up o-ring and all bearings.
 
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