Cleaning inside of motor, out of car?

[FKNFASTM5]

Hey guys, going to put some more hours into the project and wanted to get the motor cleaned up (the inside).

I pulled the pan of my M52, which is on a stand right now, and it has some sludgy gunk in it, and i am assuming that the block would have some of that same gunk.

So, my question is, how do i go about flushing the motor out and get it ready to throw back in?

All the help is appreciated,
Mike

[jlevie]

I'd scrape out what I could from the block, but would not use solvent or anything else on an assembled engine. You don't want to take a chance on contaminating the oil system or bearings. Once the engine is in the car and running, several oil/filter changes at 1-2k intervals will clean up the engine internals. During each driving interval a 20-30 minute sustained highway speed trip each week will help clean the engine.

[Cletonius]

What jlevie suggests will work but you could also try autorx if it's really nasty in there. I used some in a k-car I had years ago and it really got the internals clean. Nothing bad happened after either, did another 60k on it after cleaning. It did run better too.

[AndrewBird]

You can use mineral spirits without worry of contaminating the oil. Mineral spirits is petroleum based and is basically oil.

Add a quart of automatic transmission fluid in with the oil (leave out 1 quart of oil). It's high detergent content will help clean things out. Then do an oil change after a few hundred miles. If it is really bad, you will probably need to do it a few times. Good rule of them is if the dipstick shows clean oil, not black, it's pretty clean inside.

[CHIF8008]

gasoline works great :D