1954C180
Registered User
The saying I'm familiar with is "If it's an A, you walk way. If it's a J, it's OK". I don't mind sitting behind the J engine in my 180 at all. The only things "wrong" with the O-470J are: It has 2-bolt exhaust flanges at the cylinder heads instead of the 4-bolt flanges found on later engines. This is easily rectified by having thicker / 1/4 inch flanges welded onto the stacks.... The 2-bolt flanges tend to warp and you can get leakage at the port (bad thing if you let it go un-checked...).
As others have mentioned, the J also has "lightweight" cylinder heads when compared to the later K, L, R etc. engines. This is "rectified" by being "nice" to your cylinders! (watch CHT / EGT temps carefully, operate in "conservative" mode (run a bit more fuel through the engine, don't operate lean of peak, etc.), Be mindful of shock-cooling, ensure the baffling is in good condition, and never take off with your cowl flaps closed....
If a J still has the 3-ring pistons, oil consumption can be "elevated" when compared to later engines. Maybe I'm lucky, and I don't know if I have 3-ring pistons or 4-ring pistons, but mine goes 20+ hours before I have to add a quart of oil (I think it leaks more than it burns!).
The good thing about an O-470J is, depending upon which piece of documentation you believe, the J engine is between 25lbs and 35lbs lighter than any of the later engines.
As others have mentioned, the J also has "lightweight" cylinder heads when compared to the later K, L, R etc. engines. This is "rectified" by being "nice" to your cylinders! (watch CHT / EGT temps carefully, operate in "conservative" mode (run a bit more fuel through the engine, don't operate lean of peak, etc.), Be mindful of shock-cooling, ensure the baffling is in good condition, and never take off with your cowl flaps closed....
If a J still has the 3-ring pistons, oil consumption can be "elevated" when compared to later engines. Maybe I'm lucky, and I don't know if I have 3-ring pistons or 4-ring pistons, but mine goes 20+ hours before I have to add a quart of oil (I think it leaks more than it burns!).
The good thing about an O-470J is, depending upon which piece of documentation you believe, the J engine is between 25lbs and 35lbs lighter than any of the later engines.