Oil sludge
- Thread starter Donkeye
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A compression test to make sure the head gasket is ok, tell the owner about this before starting any work (so he or she doesn't blame you for it afterward), check if junkyard engine in better shape is cheaper and in better condition.
Volvo engine?
you can do a compression test without installing the engine. Hook up a battery to the starter and jump the solenoid with a screwdriver. Do dry and wet compression tests... dry compression will likely show low depending on how long the engine has sat unused. Drop an ounce of oil in the cylinders for the wet compression test, do the tests, write down the numbers and find out what the specs are. Without knowing compression numbers you don't truly know if it's worth all the trouble of installing the engine and attempting to clean it up.
On the other hand, I've bought many many used engines, and looking for sludge/neglect is one of the first things I do before I even think about reaching for my wallet.
What's the situation? Beater car? Customer car? Personal car that will be depended upon every day? May make a difference in the course of action. If this person is installing the engine for someone and getting paid to do so, I would not install this engine. Just asking for a headache.
On the other hand, I've bought many many used engines, and looking for sludge/neglect is one of the first things I do before I even think about reaching for my wallet.
What's the situation? Beater car? Customer car? Personal car that will be depended upon every day? May make a difference in the course of action. If this person is installing the engine for someone and getting paid to do so, I would not install this engine. Just asking for a headache.
I'd pass on that particular engine.
If cleaning is attempted, it needs to be mechanically cleaned. No oil or flush is going to clear that. Drop the oil pan and see what that looks like
If cleaning is attempted, it needs to be mechanically cleaned. No oil or flush is going to clear that. Drop the oil pan and see what that looks like
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I'm guessing he didn't do 3/3K oil changes
Could be an optical illusion, but doesn't that timing chain look pretty loose too?
I would be beside myself seeing that mess if were my car. I'd manually clean it, including dropping the oil pan. Then a few short OCI's with MMO and hope for the best.
Whipcitywrencher
Site Donor 2025
Why was the engine pulled in the first place?
I agree to do a compression test and see what gives. If it has decent compression then I would wipe off the sludge I could with a rag in valve area and oil pan then do shortened oil changes with a decent oil. Basically if the engine runs and you prevent it from getting any worse you should be fine. It may never get super clean but will get better with proper oil changes,
Auto-Rx?
Auto-Rx?
Like Pete asks - why is it out of the car?
-given the option - Id pass entirely-
IF thats not an option
A compression test isn't enough, you need to do a full leak down and inspection of the timing chain assembly and slippers/ tensioners.
If its holding 90%+ or more I'd physically clean it up and re-use it.
Its already out of the car so isn't that hard to flip it over and take the pan off
If its leaking more than 8-10% per hole as its Id reman or junk it.
UD
-given the option - Id pass entirely-
IF thats not an option
A compression test isn't enough, you need to do a full leak down and inspection of the timing chain assembly and slippers/ tensioners.
If its holding 90%+ or more I'd physically clean it up and re-use it.
Its already out of the car so isn't that hard to flip it over and take the pan off
If its leaking more than 8-10% per hole as its Id reman or junk it.
UD
Depends on what he paid for the car and what he plans on doing with it. I would leave it. Change the oil and move on. I lived in an era where this didn't look too bad.
Clean it the best you can that engine has issues not including the sludge.
Tell him to manually scrape off as much as possible, and run very short oil change intervals for a while, 2000 or 3000 kms
Originally Posted by CT8
Don't do anything . You already know what the engine is. Does it run? What is the real problem .
+1
What exactly is the problem? If the engine is running fine, not misfiring, running on all cylinders, the oil pressure light is not on or flickering, then I would leave this alone.
Don't do anything . You already know what the engine is. Does it run? What is the real problem .
+1
What exactly is the problem? If the engine is running fine, not misfiring, running on all cylinders, the oil pressure light is not on or flickering, then I would leave this alone.
Like some posters stated, perform a dry and wet compression test. I had a customer that came in with a leaking valve cover gasket and wanted it changed. When I pulled the valve cover it looked exactly like above. I recommended cleaning the engine he said no, can't afford it and the car was bought used and had 5 previous owners. Recommended compression test he said no. So we just told him to run shorter OCIs to help clean some sludge out. After 5-1,000 mile OCIs it looked much better with about 30% of the sludge gone. He only drove 2 miles a day between his house and college so it took about 6-8 months to reach 1,000 miles.
The only problem with this amount of sludge is the possibility that as fresh oil may loosen this gunk too quickly and plug up the pick-up strainer in the pan and that would starve the engine for oil. I would pull off the oil pan as well and try to clean as much gunk out of the engine top/bottom first manually and then reassemble and run short oil change intervals for the next little while to clean up the rest.
The engine is already out of the vehicle so to spend an extra 1/2 hour makes sense.
The engine is already out of the vehicle so to spend an extra 1/2 hour makes sense.
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