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Building an Engine? Thorough Inspection is Important!


Building an engine can be a tough adventure for someone who's never done it before. It can be even tougher if you dont know what to expect, which is why we've decided to make this handy guide to help you inspect your internals before you begin assembling your engine! We'll cover the following areas:

• Engine Block/Cylinders
• Pistons
• Camshafts, Pushrods and Lifters
• Crankshaft and Rods
• Engine Block Inspections and Cylinder Measurements

This step is very important. Most of us are rebuilding a core engine block, and in most instances we dont know how or why the engine was removed from whatever car it came from. If you've got a complete engine, inspect it as you disassemble it and make note of any trouble spots such as odd colored oil. Keep your eyes peeled for cracks in the block. Once everything is disassembled, thoroughly clean the block and bring it to a machine shop. Cast iron engine blocks can be magnafluxed, and aluminum blocks can by dyed to check for small cracks. If everything checks out, you've got yourself a usable engine block!

Piston Measurements

Since we're talking about new internals, we'll go over how to measure new pistons for your engine. For more information on using used pistons, feel free to contact us for assistance. With new pistons on hand, use a micrometer to measure the skirt of the piston just above the pin. Lable your pistons, and make note of each pistons measurement on a piece of paper. Your machinist will need this information to know what dimension to hone the block to so that the pistons will have proper clearance in the cylinders. Check with the person doing the machining to see if their is a certain way they like to have everything noted.

Crankshaft Measurements and Connecting Rod Inspections

Connecting rods should be inspected at the big and little ends to make sure that there are no bends or twists in the rod body. New crankshafts are typically ready for assembly and dont need the kind of attention a used crank might need. With that said, they still need to be mic'd for bearing clearance and visually inspected before moving forward in the build process. Check for any scratches or gouges in the journals and have a machinist grind or polish to remove the imperfections. If the journals are unmarked, use a micrometer and measure to find which bearing size you'll need. With that information, you can accurately purchase the correct oversized or undersized bearings based on your needs.

In conclusion

Take your time and open up your boxes and examine the contents. Make note of whats included in your purchase while shopping for your parts and verify they are in the box when they arrive. Visually inspect with your eyes and also feel with your hands. Look for sharp edges, scratches, burrs, and any other imperfections and contact the manufacturer or retailer ASAP! Also be prepared to mock up your build. Measure everything in the most assembled state without being completely together. This means, connecting rods need to be assembled and measured for bearing clearances, crankshafts should be torqued to the block for main bearing clearances, etc. Know exactly what goes where, and purchase any extra items before you begin final assembly.