combatpigg

My Feedback: (3)

There are 2 definitive tests that anyone can do to an engine to tell if they have a runner[ or to see why they don't have a runner]. Take off the backplate and glow plug. With the piston at TDC, pour fuel on top of the piston and look inside the crankcase for leakage. Lower the piston and keep checking. A good engine will maintain the seal till the piston uncovers the exhaust port. Next test is to take a soda straw and insert it into the intake [make sure the intake valve is open]. Seal the straw to the intake with modelers' clay, heavy grease, etc. Tape off the exhaust port with duct tape. Now dunk the sealed up engine [back plate and head reinstalled] into water and blow into it [through the straw]with mild pressure and take note of any air bubbles. As long as the engine rotates freely with no mechanical hitches an engine that passes these other tests should run OK.