Our first-time engine builder...
Our first-time engine builder Patrick Swegles, left, carted all the greasy and rusty parts of the engine he disassembled over to Performance Automotive Warehouse in Chatsworth, California. There he was met by PAW's Tim McElroy, who was eager to explain the machining processes the engine would go through and what the best combination of parts would be for Patrick's particular application. As it turned out for Patrick, and many who want one-stop shopping, PAW was "The Home Mechanic's Warehouse."
Last month we showed you how our first-time engine (re)builder Patrick Swegles got down and greasy as he ripped into an old junkyard small-block with passion and relentless desire to learn. This month Patrick got some valuable experience on a cleaner level as he carted all of the engine's rebuildable parts over to the experts at Performance Automotive Warehouse (PAW) in Chatsworth, California. PAW is one of the world's largest performance parts distributors, but it also has a state-of-the-art in-house machining facility that allows the company to provide a high level of quality control of all the parts included in its vast assortment of engine rebuild kits.
For Patrick, the experience was both enlightening and frustrating. First, he was met at the counter by one of PAW's experts who quickly and courteously received the old parts and went over the pieces that Patrick would need when embarking on the reassembly process. The bad news came a little later after the machine shop gurus checked out all of the old parts that Patrick had dropped off. As it turned out, Patrick struck out in his first at bat, so to speak, as virtually everything he handed over was unusable. The block had a crack in the lifter valley and both heads were breached with hairline fractures in their castings. Of course it was a given that the crank would need to be turned and that each of the eight connecting rods would have to be completely reconditioned.
Despite the setback, which was actually a realistic example of what many of us have gone through at one time or another, Patrick didn't lose any motivation to follow through with his first attempt at putting a reliable Mouse motor together. In fact, you know what they say about beginner's luck. In Patrick's case, he got a good helping of it when a friend came to the rescue and sold him a good used short-block that had been sitting in the corner of his garage. Patrick was back in business.
With this good news, this month's segment for the first-time engine builder was salvaged. And thanks to the good guys at PAW, all of the typical machining processes were provided so that Patrick can move ahead and put the engine together for next month's installment. With the main engine assembly kit coming right off of PAW's shelves, plus a few add-on performance goodies, Patrick will be ready to test his skills during the assembly process. Stay tuned, our camera will be zoomed right in.
 The stock heads were given...  The stock heads were given the same treatment as the block-and unfortunately yielded the same results. Cracks were found emanating from more than one exhaust valve. Here's a couple of more pronounced examples-end result: the junk pile. |  Within a couple of days Patrick's...  Within a couple of days Patrick's enthusiasm took a blow when word came that most of what he had dropped off at PAW was junk. With a meticulous approach to engine rebuilding, PAW's experts discovered a couple of big cracks in the lifter valley of Patrick's block once it emerged from the hot tank and was Magnafluxed, a process that is accurate in proving whether a part has cracks. |  With his original parts relegated...  With his original parts relegated to the scrap bin, Patrick was quick to regroup as a friend stepped up and sold him a block. With this, the machining process was kept on track. Once the "new" block was cleared of any cracks or other problems it was put into the system and set up for a bore job. |
 Once the required bore size...  Once the required bore size was cut, the decks were checked for square and surface ground. This will provide a nice flat mounting surface for the head gaskets. |  Here's how the deck surface...  Here's how the deck surface looks after the giant flycutter has finished taking off a minimum amount of material. Note the rough-cut cylinder walls. They will be finished honed to yield the exact bore size. |  The following step for the...  The following step for the block was to be align hone. This step essentially assures that the main bearing saddles are round. This "blueprinting" step goes a long way in providing a precision and long-lasting powerplant. |
 As mentioned earlier, the...  As mentioned earlier, the cylinder walls would be honed to size. A dial bore gauge is used to zero in on what the bore diameter is. This bore dimension is determined by the piston manufacturer's tolerances. Taken into account are the expansion characteristics for the pistons being used and the type of rings that will seal the cylinder. Most bore finishes for street performance engines have a slightly rough crosshatch appearance. This helps the ductile iron and/or moly rings form a good seal. |  The honing head features different...  The honing head features different grit stones attached to a rotating mandrel that is aligned in the cylinder. A constant flow of cutting fluid is kept running on the stones so they don't gall the surface and wear out prematurely. This process is one of the most painstaking machining steps and requires a lot of operator input. If the cylinder diameter isn't monitored, and they aren't kept consistent, there's a good chance of premature engine failure. |  Once the cylinder bores are...  Once the cylinder bores are finished, PAW's technician sets out to do the steps that will allow the final assembler, in this case Patrick, to put all the parts together. Here this engine has been given a set of main bearing studs and a good coat of a rustproof paint. At this stage the cam bearings are being installed. For most do-it-yourselfers, this is a job left to the experts because the bearings have to be aligned exactly or there's a good chance that they could impede an oil hole and cause a starvation problem somewhere in the engine. That spells failure. |
 Here's the rear cam bearing...  Here's the rear cam bearing installed correctly. |  Expansion, or freeze plug,...  Expansion, or freeze plug, installation is a relatively simple procedure that the homebuilder can do. However, PAW's blocks don't leave without them being installed. |  Since Patrick's heads were...  Since Patrick's heads were unusable, the logical solution was to simply pull a good set of brand new World Product castings off of the shelf. These high-quality pieces come complete and free of any worries. The days of having your old heads remanufactured are numbered when it's so cost-effective to use new ones. Of course, if you're doing a number's matching restoration or want to save a set of original fuelie heads, that's a different story altogether. |
 Crank reconditioning is another...  Crank reconditioning is another area that is critical in having a good-running engine. Things like making sure it is straight and free of cracks are paramount. Once it makes it past those checkpoints, the balancing procedure takes center stage. Of course, engine balance requires more than just the crank, but here's the crank laden with all of the bob weights which represent the connecting rod and piston weight. |  The computer balance machine...  The computer balance machine determines where metal must be added or removed to bring the crank to perfect balance. Here the machinist is getting ready to remove some. |  As mentioned above, the balance...  As mentioned above, the balance procedure includes all of the parts from the rotating assembly such as the pistons and rods. Here, the weight of the rods and pistons are determined. When finished, each rod will weigh the same as will each piston. If needed, the parts are machined to coincide with the lightest of the set. |
 The pistons in Patrick's engine...  The pistons in Patrick's engine will be pressed onto the rods. This process requires heating up the small end of the rod and quickly inserting the wrist pin while the metal has expanded due to the heat. |  Rod reconditioning includes...  Rod reconditioning includes having both ends honed until they are within tolerance of being perfectly round. Another component to a good piston/rod combination is having the two parts properly aligned in relationship with one another. That's what this machine does. |  Final machine process for...  Final machine process for Patrick's parts was the finish polish of the crank journals. Once this is complete our first-time-engine-builder, Patrick, will be ready to try his hand at putting everything together. |