My oil is nasty! About 2 months ago rebuilt the top end with new heads. When I tore the engine apart on the valve covers/in the lifter valley there was quite a bit of sludge/slime. Since then I have done a few oil changes to try and flush some of that crap out of the engine. On the last change I had added seafoam to the oil and changed it after about 250 miles. It came out blacker than night it was nasty. But even after 500 miles on this oil change the oil is turning dark and nasty again. I am running Mobil 1 clean high mileage.

Only thing I can think of is when I pulled the heads (due to cracks and leaking into cylinder) there was a tiny bit of rust on the cylinder wall. It was very slight, and I used ATF and a bit of super fine sandpaper to get the rust out. It doesnt have the hatch marks there, but I have not lost any oil since it has been rebuilt. It is a 95 with about 132k on the clock. Is this just something I am going to have to live with? Or is something wrong? Any ideas would be appreciated.

Thanks

Jason

 

The black oil is probably from the sea foam. The sea foam loosened up all the sludge in your engine, where else is it going to go besides in the oil?

How long does the botttle say to run the engine with that in the oil, 500 miles seems a bit much. I would change the oil once or twice more and i'll bet it cleans up.

 

Use good filters and just change the oil frequently for a while. Not much else ya can do about that. But if there is sludge in there are you doing alot of short trip driving?

 

Well, the seafoam was put in and changed at about 250 miles, maybe a little less than that, but the new oil put in after the seafoam was gross after 500 miles too. I dont know if seafoam sticks around for a while after the first change.

I really only drive to work and back, maybe to the store every once in a while, but I am a workaholic so thats my life until I start med school in the fall so i dunno. I drive maybe 15 miles to work and back I dont know if that is considered a short trip. Thanks for the info.

 

Maybe see what it does during the next oil change. The Seafoam is supposed to be some pretty strong stuff and is supposed to turn the oil pitch black from what I hear.

 

the bitog forum said to not leave the seafoam in the oil more than 200 miles, and not to push the engine too hard either as the seafoam thins out your oil. Redline oil is supposed to have some de-sludging ability due to it's composition (esters or something).

the big de-sludger promoted there is auto-rx. there are so many before/after valvetrain photos of that product that i think there might be something to it (ie, not snakeoil)

 

I heard auto-rx is much better than seafoam.

There's no way you could have gotten ALL of the seafoam out on the first oil change. Just use regular dino oil until it starts cleaning up again.