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Discussion Starter · #1 · (Edited)
A few months ago, I found heavy oil deposits when the valve cover was removed to fix small leaks, and later noise some chain noise at idle. The chain tensioner was removed and found extended past the limit.

The oil pan was removed for cleaning. The oil screen was about 80% plugged, metal flakes were found in the bottom of the pan and the rod bearings were shot.

The last repair shop I consulted is familiar with the problem, and has examples of scrapped engines due to chains and guides wearing out and breaking, including from newer 9-3 models. The problem is not unique to Saab. Since I started looking into it, I have heard of other makes with the same issues, cars from the same period, 5-10 years old. It does not seem to be quite the same as the "sludging" in 9-3 models, but similar.

The following is a short history, for anyone who may have the same problem, or is trying to catch it at an earlier stage.

Summary:

1) Valve cover removed to fix leaks and for inspection.
2) Amsoil engine flush tried with one oil change. (That is a 20-minute treatment before an oil change)
3) Oil analysis by Blackstone Labs (excessive lead, elevated copper, and some fuel in the oil) See link below for details.
4) Oil pressure, compression, leak-down tests were done. Leadk-down showed leakage on one cylinder, which returned to normal after a couple tanks of fuel with Lubro-Moly valve cleaner.
5) Auto-Rx flush and rinse cycle, 3500 miles total and two oil changes.
6) Timing chain tensioner removed and measured, found extended past limit.
7) Oilpan removed, oil screen found about 80% plugged even after the two engine flushes, metal flakes found in the bottom and rod bearings were worn to the point of serious damage.

Engine w. valve cover removed:



Closeup of timing chain sprocket:




Link to larger pics of engine and some test results:
http://www.geocities.com/ng900set/Engine/eng.html

Post on oil pan cleaning and bearing inspection:
http://www.saabcentral.com/forums/showthread.php?t=51450

Post on bearing replacement:
http://www.saabcentral.com/forums/showthread.php?t=53285
 

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Oh Yuk! looks like the bottom of the barbie after several 1/2 pounders and a brace of lamb chops!

I thought this crud was only to be found in old MGs, Triumphs and moggie minors.

Good luck with the rebuild :eek:

Hope the pistons and liners are still OK.
 

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Im not trying to hijack your thread, but heres my oil pan and engine pistons at 148k, just for comparison. Used conventional castrol oil every 2-3k miles.
I actually didn't take apart the oil screen to clean it out.. next time I am in there I will. I haven't ran any auto rx or any oil flush, that will probably be down the road sometime as I think my oil pan is pretty good.



http://www.9xstudios.com/shosko/TR/photobooks/saab/pages/IMG_0934.htm

http://www.9xstudios.com/shosko/TR/photobooks/saab/pages/IMG_0936.htm
 

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Noticed that you're both running conventional oil. Mines had Mobil 1 in it since it was bought. Done 80,000 and when I got the rocker cover off, there was just a slight colouration and a small amount of soft carbon wisps at the chain end. Generally looking "new". Nothing like either of these sets of photos.

Oil gets changed every 9,000. Can't comment on the bottom end, although the filter connection/oilway is not discoloured.

I just wish the previous owner had the clutch/cable replaced, before it wore-out the synchros :cry:
 

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Here is mine looks like with regular oil at around 115k miles, usually of the 10w-30 or 10w-40 (depending on the season):

 

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So what's going on? Maybe:-

Cheaper oil.
Hours sitting in traffic.
Short journeys.
High ambient temperatures.
Long service intervals.
High speeds and long journeys.
Bad combustion - fuel and soot in the oil.
Bad combustion running lean and too hot.

I know my model engines become black and sooty running on castor or motorcycle 2T oil. Full synthetic has a big effect on cleanliness. But as you are running on mineral oil, what's the difference Slaab4Life?
 

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Discussion Starter · #7 ·
I wish I could post the answer, and not just pics of a prematurely worn engine. The first items are on top of my list of suspects.

Short trips, cold winters: Car went from being used 75% on the hwy to several years of multiple short trips per day in start/stop traffic. Oil changes were stepped up, but perhaps not enough.

High temps? No, maybe two weeks per year... <LOL>

Long service intervals: Not. I may have neglected the cabin filter and that unfortunate hand brake, but none of the basic engine stuff. High speeds and long journeys, not for a few years.

Bad combustion, possible I suppose. From the UOA, there is more fuel in the oil than there should be, but I am guessing that is because of engine wear and blow-by. Who knows which came first.

Maybe a combination of poor crank case ventilation (not unique to Saab), in combination with short trips in cold weather. Fumes and water vapor not vented well enough from the crank case and condense as the engine cools. Oil quality degrades.

Or, a small oil reserve and an oil cooler that can't remove heat fast enough - in other words oil, cooked the old fashined way. If you do a few runs with the air dams off on a warm day, and then pop the hood quickly, the blast of heat from the turbo and exhaust manifold area is incredible. (I said airdams off, so the heat can rise when you open the hood). Turbine oil seal failed at 84k miles (I prefer not to remember that incident).
 

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Just a brief history on my car, its been in marietta georgia all its life (no winters), and the oil was changed every 2-3k religiously. Granted mine isnt the cleanest, but its in great shape. What conditions has your car been in PMI?
 

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Discussion Starter · #9 ·
sethsev7n said:
What conditions has your car been in PMI?
Daily driver, normal combination of 25/75 city and hwy mileage for about 4 yrs, then 3-4 yrs of mainly short trips multiple drips per day. More hwy mileage in the last year again. Cold winters, lots of road salt, start/stop traffic, parked mostly outside.
 
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