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Hey guys: I finished getting the cylinders off the motor ysterday. Now I have to figure out how to remove the pistons. Yes, I have read the manual, but I am slow (getting slower every day) and seem to have a propensity to make mistakes. I guess I just do not think the thing through enough. Fortunately, I found Roger Smith's discussion of the top over haul of his 3300 & got revitalized.
Has anyone come up with an easy way to cover the inside of the cylinder while bead blasting the exterior of the cylinder to remove the rust etc.
Top-end overhaul? That's quite an adventure. How many hours and what is wrong with the motor?
You can remove the pistons with the rods, or if you don't intend to replace the rod bearings then you can just remove the pistons.
Hey Steve: Yes, I agree it is quite an undertaking. My motor has 420 hrs. TT. I had several low compressions at the 100 hr. and found that both valves on # 3 cyl showed stem wear and poor valve head to seat sealing. My
TO RPM had dropped about 100 RPM & oil consumption was increasing rapidly. I also found that most all cylinders were out of round by about 5 - 6 thousands. I had the newer 12 point nuts put on last year, which helped, but apparently did not solve the problem.
I have contacted Jim McCormick to work on the heads & cylinders. Are you happy with his work?
Sorry your having problems. 420 hours is a bit soon for the issues you describe, even for a Jabiru motor.
I have always had good luck with Jim McCormick. Treat him with respect and don't blame him for the engineering problems the engine has - he did not design the motor, he just supports it.
Hey Steve: Did you take the heads apart, or send them to Jim as is (minus push rods of course)
You can do it ether way. The machine shop will want them dissembled. If don't want to do it, Jim will have to do it for you.