Inspect the spark plug: 5. Install the new spark plug or the cleaned spark plug If the electrode is oily, clean it using a clean, dry into the engine. Gasket-style: Finger-tighten until the rag. If the electrode has deposits on it, polish it gasket contacts the cylinder head, then about 1/2-2/3 using emery paper.. I am an engineer and have been using this printer to prototype my designs with great success. I have been able to print parts using PLA, ABS, & TPU materials (The ABS is challenging but possible). If you are new to 3D printing it might take a little while to learn how to use the machine and software but a. "/>Predator 173cc engine