Our standard block service for your engine block includes cleaning, decking, honing, and final prep. Here’s some more about each step in the process.
Cleaning the Block
A thorough cleaning is the first step in our machining process. It lays the foundation for all the work we do. It will make your engine look like brand new, too!
We process Cast iron engine blocks in our Thermal Cleaning Unit. We place your block in our oven which is then at over 500°F. This turns any oil, grease, paint, and other contaminants into ash. We then blast the ash away in our shot peen and tumbler machine.
We process Aluminum engine blocks in a fundamentally different way. Aluminum blocks cannot be baked due to the ductile iron cylinder sleeves, which expand at different rates. We place your block in our hot tank, wash and rinse it. We then we move it to our media blaster to remove any corrosion and oxidation.
Decking the Block
After your block is clean, we transfer it to our CNC machine. At this point where we affix the block and measure to verify it is parallel to the cutting plane. The machine then removes material until your deck surface is uniform and flat.
We offer standard decking on most engine types, including
– Single-cylinder motorcycle/ATV engines
– Inline engines
– V engines
Square-Decking the Block – a special note
Most engines leave the manufacturer with less than ideal tolerances. Sometimes with as much as ten thousandths (>0.010″) of an inch deflection across the deck surface. Specifically the angle of the deck surface relative to the centerline of the crankshaft and camshaft. We utilize a specialized fixture manufactured by BHJ specifically for 90°V overhead valve engines. This fixture enables our CNC resurfacer to machine the deck surface perpendicular to the crankshaft. This results in an engine that has a perfect 90° between both banks of the V and 45° on each side of centerline. This process allows us to correct the variation across the surface down to within one thousandth (<0.001″) of an inch.
Honing the Cylinders
Although proper boring and honing is critical for high performance and race engines, it’s very important for street cars as well. If the piston-to-wall clearance is off by even a thousandth of an inch too much, it can cause premature engine failure.
After measuring your pistons to within 0.00005″ inches, we machine a custom clearance accurate to the nearest ten-thousandth (0.0001″) just for your application. We hone to final size with aid of a torque plate (if applicable). This procedure is performed to simulate cylinder distortion when the heads are installed and torqued.
We are able machine your engine block to a set size if you wish. However, we always advise you to bring the set of pistons you wish to use or let us purchase a recommended set for you.
Final Cleaning and Preparation
After we bore your cylinders to final size, we put the block in our hot tank one final time and remove any oil and metal shavings. We then treat the cylinder walls to prevent any surface rust. We will take any final measurements which we record and provide to you in the form of a block qualification sheet.