The dreaded sludge

[9-5er]

Just bought a 9-5 aero 2.3 auto, recently changed the oil, put 5w40 mobile full synthetic tbt in it, and I know after owning two previous saabs , a 900s and a 9-3, I should have done it, but it's in such great shape didn't feel the need at the time to dump the sump and check it for sludge or condition. I' changing the plugs so decided to peek under the valve cover. My stomach sank, it has noticeable sludge, there's no doubt in my mind now that I'm going to have to dump the sump and clean. But before I do so, opinions on "de-sludging"? Should I put the valve cover back on and run seafoam in it? Or simply try and scrap and clean whatever I can on top with a rag? Ideas opinions are most welcome at this point.

[nordwulf]

The sludge you see on the top of the engine causes no harm so I would just leave it. And it actually doesn't look all that bad.

Adding any kind of additive to your engine oil may cause more harm than good. As far as I understand, the main problem is a clogged pickup filter and oil passages inside the engine that get smaller or blocked completely. So drop the sump first and see what's going on in there. And use quality synthetic engine oil.

There is a lot of information when you google 'desludge engine' and a lot of opinions on different methods. However, I am not an expert either so proceed with caution.

[XLR99]

I'm also a non-expert, but to me that really doesn't look bad.
I believe that you'll get a gentle de-sludging effect from using the M1, just change it every 5k.
Also check to see if yours has the most updated PCV system: V6 or 7 ? I can't remember if it was 02 or 03 that had the most recent iteration. The newer the car, the less susceptible to sludge it should be (given routine maintenance and using M1 like Saab recommended)

[9-5er]

Gentlemen Thank you for the responses. Yes it does in fact have the PCV upgrade. I dropped the pan and it appears someone before me tried to clean a large part of the pan. It still had a few large coffee grounds in it though. The screen at the pick up tube was clear no particles attached as I have seen before with my other cars. As for the top and sending any cleaning agent thru the engine, I concur, no doubt will add more issues than I want. so buttoned up the top and have a the pickup tube soaking in a pan of gasoline to dislodge some hard to get to crusty sludge. Unless you guys think its a bad idea? again thanks for the input.

[cjapeterborough]

Gentlemen Thank you for the responses. Yes it does in fact have the PCV upgrade. I dropped the pan and it appears someone before me tried to clean a large part of the pan. It still had a few large coffee grounds in it though. The screen at the pick up tube was clear no particles attached as I have seen before with my other cars. As for the top and sending any cleaning agent thru the engine, I concur, no doubt will add more issues than I want. so buttoned up the top and have a the pickup tube soaking in a pan of gasoline to dislodge some hard to get to crusty sludge. Unless you guys think its a bad idea? again thanks for the input.

I have three 9-5's 1999(120K Miles),2001(90K) and the latest...2008(80K)........ yours doesnt look that bad

On the two early cars they had the latest PCV update fitted at an early stage and regularly maintained by myself with synth oil changes 5K.
I have dropped the sump twice on each of the above probably 5 years apart and had the cam cover off the vehicles.
On each occasion there was very little evidence of sludge....but the process gives peace of mind and confidence in your vehicle.

IMHO a lot of the black sludge comes from the earlier PCV's system bad design and comes from the pipes turning to mush and ending back in the sump.

I clean everything with a power washer and for the tough to shift hard varnish spots some fine wire wool and again soap and water.
Takes some elbow grease and as long as you wipe over with a WD40 soaked rag afterward there is no problem with rust etc


I have just purchased the MY2008(which has the last PCV update by default) and for peace of mind dropped the sump and lifted the cam cover..........again no issues.

[XLR99]

I think you can remove the screen from the tube to clean it better (might as well since it's already on the bench)
I'm not sure what the best solvent for the sludge would be? Brake cleaner, or maybe some seafoam to soak it in for a bit?
I'm going to drop the pan on my car when I do the subframe/suspension bushings in the near future, same reason you did, peace of mind.
Not sludge related, but I also add a magnetic drain plug to all my cars to pull out whatever ferrous material is floating around and not grabbed by the filter.

[9-5er]

I think you can remove the screen from the tube to clean it better (might as well since it's already on the bench)
I'm not sure what the best solvent for the sludge would be? Brake cleaner, or maybe some seafoam to soak it in for a bit?
I'm going to drop the pan on my car when I do the subframe/suspension bushings in the near future, same reason you did, peace of mind.
Not sludge related, but I also add a magnetic drain plug to all my cars to pull out whatever ferrous material is floating around and not grabbed by the filter.

A magnetic drain plug? That's a great idea.

[cjapeterborough]

I think you can remove the screen from the tube to clean it better (might as well since it's already on the bench)
I'm not sure what the best solvent for the sludge would be? Brake cleaner, or maybe some seafoam to soak it in for a bit?
I'm going to drop the pan on my car when I do the subframe/suspension bushings in the near future, same reason you did, peace of mind.
Not sludge related, but I also add a magnetic drain plug to all my cars to pull out whatever ferrous material is floating around and not grabbed by the filter.

I used the original how to guide on the serioussaab site..........you can use whatever solvent you like but it will get expensive if you use brake cleaner.
You do a full dissasembly of the oil pickup ....I cleaned the mesh with a toothbrush.

Mosts guides suggest changing the o rings on the pickup pipe,transfer pipe across the bottom of the sump and the return pipe from the PCV tank.The only one I have ever changed is the one on the pickup pipe as the rest of the seals stay in place and are not disturbed(uness of course you take those out too)


SeriousSAAB procedures archive: dropping and cleaning the SAAB 9-5 sump

[9-5er]

Y I took the pipe out and getting O rings for them as well. In getting my mistress back together, Heres a little FYI if some of you didn't know already, no need to use expensive chems and degreasers, Dawn dishsoap and a cheap dish scrubby pad. LOL. and leaves your motorhead hands nice and soft. And it does the job very nicely!

[Pbuck1]

...magnetic drain plug. Where did you get it, whats part number.? Anyone using one of the big magnets which are placed on the outside of the oil filter?