The Stovebolt Site Forums The Shop Area Engine Shop Block Prep before assembly

My block is stripped and has been back from the machinist for a while. I left the plastic off one night and the garage door open and it rained. I have some light flash rust on the cylinder bores. Smooth to the touch. I sprayed the block down with WD40 ASAP to keep it from getting worse and it hasn't.

How should I proceed in preparing the block for assembly?

Smother the cylinders with engine oil. Wipe clean, then re-smother with engine oil. Check the lifter bores while you are at it.

Flash rust is actually a good thing- - -it means the block was cleaned well after boring/honing. I'd suggest giving the cylinders another good scrubdown with HOT water, laundry detergent, and a stiff-bristle scrub brush, then a boiling water rinse. Then give it a light coat of motor oil on a very clean rag to prevent further rusting before you assemble it. There's no such thing as cylinder walls that are too clean.
Jerry

I could easily get hot water from the bath, but I'm trying to think how to get boiling water in a sufficient enough quantity for a rinse. I have a tea kettle, but only big enough for a cylinder or two and would have to re-fill/boil. How do you normally go about this Jerry?

Thanks for the info so far!

I put a BIG stock pot on the side burner of my gas grill and fire it up. I've got a stainless stock pot set that I use for canning, big batches of chili or beef stew, etc., It holds about 5 gallons. Since it's holding only water, it serves double duty as a rinse water pot for building engines. I just use a small saucepan as a dipper and flood the cylinders repeatedly with the scalding water. It evaporates almost instantly and I oil 'em down right away.
Jerry

A hot car wash also works. I use Castrol degreaser and stiff brush on the cylinders and then hit the car wash, I have one a few blocks away. The hot water really cleans and it gives me one more chance to clean out the water jackets. Take a towel to dry the cylinders and hit them with oil or WD40 ASAP. Flash rust is not all bad, most of it wipes right off.

Joe

All sounds good. Could rent a steam cleaner too I guess.

The rust on the cylinders didn't just wipe off with a towel and WD40. Like I stated, you don't feel the rust to the touch. Should I take a hone to them to will they be okay?

The rust will scrub off with a stiff bristle fiber brush, and that's better than putting more abrasive into the pores of the metal. Even if there's a stain left, the rings will polish it away within a few minutes' running time. It's amazing how little hone residue it takes to totally ruin a set of rings. I found out the hard way- - - -completely wore out new rings on a Rambler American flathead 6 in 2500 miles of driving, and I thought I had done a thorough cleanup after honing the cylinders!
Jerry