If you are rebuilding an engine and replacing your piston rings it is normally suggested that you hone the cylinder walls to prepare them before assembly. This might not always be the case but most of the time you don’t want to skip this step because honing your cylinder walls is what keeps the oil on them.
For best results you are suppose to create a 45 degree cross hatch pattern on the cylinder wall. The way that you do this is to run your hone at an appropriate rpm and stroke the cylinder wall at a corresponding stroke speed to create that 45 degree cross hatch angle.
If your crosshatch angle is too high then oil will not be retained on the cylinder wall. If your stroke is too low of an angle then you will have higher / faster wear on your piston rings.
How To Select The Right Ball Hone For Your Engine
There are two main things that you want to look for when selecting a ball hone. The first is the diameter of the hone. It should be the appropriate size for your cylinder dimension width. Manufacturers of these hones should be able to spec you the right hone based on your engine but if you make modifications to your engine you want to make sure that they know this before you place your order.
If you are over sizing your cylinders then you normally use the normal size hone which has in it the ability to hone normally oversized cylinders. When in doubt ask before you buy.
The next thing you need to look for when selecting the right hone for your engine is the grit of the hone. Manufacturers will recommend a grit to be used from 60 grit to 600 grit. The lowest grit is the most aggressive and it would be used to repair damage in a cylinder. However if you are thinking about using 60 grit hone on your engine you really need to be sending it to a machine shop.The higher grit hones are used for cylinder walls that have a special coating. The average or normal grits used for honing are somewhere around 200 grit to 400 grit depending on the manufacturer.
The type of piston rings you are using are also important when selecting a grit for your hone. Normal iron rings will use a lower grit and moly and plasma rings will use a much higher grit.]
How To Use A Ball Hone To Prepare Your Cylinder Walls
As said above the most important things are selecting the right hone and then using it in a way that will create a 45 degree crosshatch pattern on your cylinder wall.
The speed that you stroke the cylinder and the RPM of the drill will set the angle of the crosshatch pattern.
Before you begin you want to prep the hone by soaking it in oil and prepare the engine by cleaning it thoroughly and then preparing the cylinder walls with oil. You can never really clean the engine too much before you begin because any debris introduced when you hone will cause problems and the size of the debris that can cause problems is extremely small.
A 30 weight engine oil will work well or use manufacturer’s suggested hone oil.
How fast should you stroke the cylinder to get that pattern? Most people say you do it as fast as you possibly can. However not everyone is the same so it is important that you make a couple passes and then adjust your RPM on the drill to reach the appropriate angle. You only need to run the drill for about 15 seconds to see the crosshatch in a unprepared bore.
It should normally take between 50 and 100 strokes to prepare the cylinder with the ball hone. Area that has not been prepared by the hone will look grey in comparison to conditioned area. Continue stroking until the entire cylinder is uniform.
Post Cleanup Of Your Honed Engine Cylinder
Just like precleaning is extremely important you also want to take as much care or even more care after you hone your cylinder walls to make sure that all particulate is removed from the block before you continue with assembly.
Although I have seen people use a ball hone in an engine that still has its bearings it is really in your best interest to completely strip down the engine and remove all parts other than just the block before you hone the cylinder walls because you are simply risking to much.
The debris from honing can get into everything including your lifters, oil pickup just basically everything and the result will be quite a lot of damage to your bearings.
Make sure that you always follow the manufacturer’s recommendation on what grit and size to use for your engine and I suggest you stay away from those aluminum blocks that have plated cylinder walls without a steel insert. They are very thin coatings and you are best to have someone do that who does it all the time.