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Omitting Tach shaft

krhea

Well Known Member
I recently overhauled my narrow deck O-320D2A. I installed EFII ignitions when i installed the engine in my RV7. The engine had 741 hours on it and was built in 1982 by Mattituck. Since the tach shaft had some wear at the seal area and the cross pin was worn, i elected not to reinstall them. RPM is off the ignition system. It is a two piece cam. I did not attempt to block-off any oil flow down the cam either. Now i have a little oil coming out the overflow. I really don't want to remove the engine, remove the accessory case and reinstall the tach shaft, or a seal plug. the oil slinger is in place. Could i make some sort of a cover for the overflow fitting that would vent the crankcase, but prevent oil from being thrown up the fitting?
 
Ac spruce has a cover for the tach drive pn# 10-06754. If the slinger is in place that should keep anything away from the breather unless you are trying to say that oil is passing through the center of the cam and out. The only cure for that is to put the tach shaft Back in place but you don?t have to remove the engine for that. The accessory case and sump will come off with the engine mounted.
Ryan
 
Removing the tach shaft doesn't change the oil flow, though it does reduce the area some in the breather exit. There is a shroud installed on the case cover at the breather outlet and this is designed the keep splash out of the breather exit. The tach shaft is not integral in that function.

I suggest that your breather hose rise at least a couple of inches before pointing down. This will help a little. But, you will always get drips. The atomized oil carried in the breather air will cling to the hose wall and begin to coalesce with other oil drops until they are big enough and gravity brings them to the hose exit. An air oil separator will help.

Larry
 
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Omitting tach shaft

I suspected as much after the fact, 6 quarts is my full level, will remove the barb fitting and see if I can fabricate a shield to catch;oil mist and let it condense and still keep same tubular cross section.

Thanks

Keith
 
Omitting tach shaft

I suspected as much after the fact, 6 quarts is my full level, will remove the barb fitting and see if I can fabricate a shield to catch;oil mist and let it condense and still keep same tubular cross section.

Thanks

Keith
 
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