The Stovebolt Site Forums The Shop Area Engine Shop stones on cyl hone

Got the motor torn down(1955 235) and found it had been bored .040 over. Motor was rebuilt truck wrecked, motor pulled and has set in a barn for 40+ years.I am ready to clean up the cyls (some surface rust). My Question is are 180 grit stones to aggresive for just a clean up on the cyls. I also have 280 grit stones. There is just a slight ring groove, you can't even feel it with a finger nail. THANKS in advance for any replies!!!

You really need to check your cylinder wall clearance first and make sure the block doesn't need to be bored. Since you are already seeing a ridge, that should tell you that you have enough wear that honing them may be a moot point. As for the grit, it depends a lot on the rings you will be using, but even for cast rings the 180 is a little too rough unless your doing a "shadetree" rebuild. You also need to inspect and mic the pistons to make sure they are going to be reusable.

If it just needs clean up & deglazing the hone with all the silicone balls works real good. After any honeing scrub the walls down with soapy water to remove the material out of the pores.

First question- - - -are you using a rigid hone or a spring-loaded glaze breaker? The 280 grit stones in the glaze breaker will not remove a noticeable amount of metal. All the fine grit stones do is create a slight amount of roughness to assist in ring seating. A rigid hone is used after a rebore job to remove 2-3 thousandths of metal and eliminate the spiral grooves left by the boring cutter.

Put an old compression ring into the cylinder at the very top of the ring travel, up against the ridge, and measure the gap with some stacked-up feeler gauge blades. Then use a piston to push the ring down to the bottom of the cylinder and measure the gap again. Subtract the bottom gap from the top number and divide the difference by 3. The result will be the cylinder taper in thousandths of an inch. If it's more than 5, rebore the block.
Jerry

Remember the old circumference formula- - - - C = Pi X diameter?

By dividing the difference in circumference (the gap change) by 3, you get the difference in diameter from top to bottom. The really anal-retentive types will go ahead and use Pi to as many decimal places as their calculator can handle. 3 is close enough for me for a guesstimate of cylinder taper.
Jerry

Now that's a pretty handy piece of info Professor Jerry. Putting that in the archive.

An old piston ring and a feeler gauge are a lot cheaper than an inside micrometer, too!
Jerry

Spring loaded glaze breaker. There is no ring groove just a little mark on one side of each the cyl.(the start of a ring groove). The only thing i was going to do was clean up the cyls. to get rid of the surface rust,(or deglaze) before it goes to the machine shop for boil and magnaflux. Like I said Motor was rebuilt, truck wrecked, motor pulled and it has sat in a barn for 40+ years. And again THANKS for the replies Eric

If you can get to a power washer, you can save some money at the repair shop. If they boil the block, you need new cam bearings and freeze plugs. A power washer will do just fine if you presoak the block with Castrol degreaser or like material. Its really handy if you have the pinpoint tip (red one) for your power washer, you can clean out bolt holes and oil passages easier plus break-up crude in the block drain hole.

As far as the cylinders go, a good deglazing with ball hone will do wonders, its been done hundreds of times with out problems. I have been using Purple Power in a spray bottle as a honing fluid, not only does it wash away the grit as you hone, it speeds up the cleaning of the cylinders. I don't really see any difference in the bores since switch from oil to soap when honing. You still need to really get in there and scrub the walls down to remove any remaining grit.

Joe