rust in cylinders

[rhb1999]

Hello, I'm kind of new here so bear with me. I thought if anyone can help you guys can. I want to save the cylinders in this engine I have. All the cylinders are free of any ridges on their tops. The problem is they have surface rust. I've been spraying PB Blaster on them, but I haven't tried to turn the engine yet. Should I try to remove the pistons? I thought if I got the pistons out, I could get someone to hone them out. (I never used a cylinder hone.) Would some kind of rust remover help OR could this damage the cylinder's surface OR should I have the block hot tanked after getting the pistons out and then see what they look like? Also, what type of hone should be used on a this kind of job. Thanks in advance.

[52deluxe]

if its just light surface rust you could probably spray solvents in the cylinders to losen it. then turn over by hand to make sure it does not bind anywhere and fire it up "its gonna smoke bad for a few min." if its anything more then just minor suface rust id pull the pistons and use a cylinder hone. its rather easy to do just make sure you dont hit the crank and keep using a updown motion "you will see about a 45 degree angle pattern if going about right." keep the hone oiled well and go slow, faster is not better. im not exactly sure how "by the book" that is but its how i was taught and always worked for me. make sure before you reassemble the engine to clean the cylinders good to remove any abrasives from the cylinder walls that could cause scoring.

[RocketDude]

Judging by the fact you know there is no cylinder ridge, it sound like you already have the heads off, so it may be a little late to start it up..! It would help to know what you are doing, and why, and at what stage of disassebly you are at. If the heads are off, and you just want to get rust off before removing the pistons, get a flex brush hone and hone the holes lightly, with the pistons in. A brush hone is made up of a bunch of little abrasive balls mounted on flexable plastic stems. You won't damage the hone, or the pistons with that hone.

If the rust is really light, you may not even need to hone them, just oil the wall and push the pistons out. Make very sure, use your fingernail, that there is no ridge. It doesn't take much ridge to catch a ring. Rare not to have any ridge.

A stone hone is great for after boring, but since brush hones were invented, I've never gone back to stones. The come in all sizes, even down to brake cylinder sizes. The work great, and leave a beautiful pattern.

After the pistons are out, you can hone the cylinder again to make them perfect for the new rings I assume you are going to install.

As mentioned above, make sure to wash your cyl walls good with hot soapy water, dry them, and wipe some WD-40 on the walls to prevent rust until you're ready to put the pistons back in.

Stone hones are fine. They have been around for a long time and work well. The stones can break if they strike something. Brush hones are bullet proof and work great.

http://www.brushresearch.com/Index.cfm/FuseAction/home.FlexTools/Products/GBD.htm

Check here for a picture of what I'm talking about....

[rhb1999]

Thanks RocketDude, You answered most of my questions. I have heard that a brush hone is the thing to use on something like this. I found this short block engine at a junkyard (carburetored 305 Chevy factory roller) hence the rust. It looks like it's been remanufactured; it's even been decked. Most of the cylinders have light surface rust, one or two are a little heavier. Not to go up and down too slow or too fast. A slower turning drill motor gives me better control. This sound right? Thanks again.

[RocketDude]

True, you don't want to go too fast. I put some 30# oil in a coffee can and stick the brush in in, so it's plenty lubed, put the brush next to the hole and get it moving before you enter the hole. then move the hone in and out sorta slow, and count about ten strokes. Take a rag and wipe the walls to see how it looks. You might have to do it again, depending how much rust you have. You will love how pretty the brush leaves the holes.

Good luck.....