I use kero.
I use nylon pipe cleaners for the oil galleys and the water jackets... I find that the normal ones leave lint.
With the bores and deck I clean them using paper towel and a tiny smiggy little bit of engine oil. You can get them spotless using dry towels and then put a tiny bit of oil on the paper towel and scrub the bore again and you
will get more honing oil and crap off it. I just keep going till the paper towels come out dry and as clean as they were off the roll. Then inspect to make sure they didn't leave any lint behind (which if you use the right paper towels, they won't... but it never hurts to check).
If an engine has been tanked, do not assume it is clean enough for assembly. You will be able to get it cleaner and often while in the tank crap floats into places it shouldn't be,,, so always clean it again after getting it tanked.

This is another one of those things that Phat Kat found out the hard way

I thought;
"oh yeah, give it a rinse and a blow out and she'll be right for assembly,, c'mon its been tanked its probably clean enough already"
Well,, that particular engine (my first) lasted.... ewww about an hour!
Like sgc and everyone else said... unless the towels or rags you are using are coming out of the motor cleaner than they went in,,, its still not clean enough to assemble
So at least your a smarter cookie than me in that you thought of cleaning it again
Doc thats pretty interesting, I've heard of other people using diesel for a degreaser... I've not tried it myself... but something I do do occasionally if I know I'm going to pull a motor apart soon, is I run diesel engine oil (in the same weight as the engine oil I'd normally use) in it for 50-60 km. It has a higher level of detergants in it so it comes apart much cleaner.
Some people could argue that it isn't a good idea running diesel oil in a petrol engine because it is ""too clean"" or something and it could do damage. I personally have never had a problem doing it if its only 50 odd clicks. I don't know what effects it could have over a long period of using it though. Never had any reason to want to find out
