Date:Oct. 06, 2023


Brief Description:No spill process for flushing the cylinders.

Cylinder Solvent Flush Tool

While chasing the cause of an increase in oil consumption, I decided to borescope the cylinders and valves.  I noticed that the #6 cylinder had some slightly oily plugs (top and bottom).  Once the scope was inside the cylinder I noticed some standing oil on the bottom of the cylinder.  I decided this would be a good time to try out the Savvy Aviation oil control ring solvent flush.  If you follow the procedure you will have the balance of solvent spill out the bottom spark plug hole when you complete the procedure on each cylinder.  I was not keen on spilling solvent/oil mix all over the ground so I came up with a tool to solve the problem.  I showed my idea to Carl and Tom, and Tom kindly offered to modify a spark plug to assist in my tool creation.  

I threaded the tool into the bottom spark plug hole, brought the cylinder up on the compression stroke, used a socket extension to gauge where the piston was so that I could use a similar amount of fluid on each cylinder, filled the cylinder until the top plug just started to seep (have someone pull the prop back just a touch and none will spill), installed a plug in the top hole, and then completed the procedure.  I would recommend folding a towel over a few times to give your hands a break while pushing/pulling on the prop.  One thing I had not considered is that the cylinders will create compression 120 degrees apart.  This means that you will have 2 cylinders where the prop is parallel-ish to the ground, two where it is near vertical-ish and two somewhere in-between when it is making compression.  Do the cylinders where it is vertical-ish first as you have the least mechanical advantage and it takes more effort.  The tool worked very well and was well worth the effort to assemble.



Pair of modified spark plug/nipples and tool with E-mag 14mm to 18mm adapter.

Home Depot shopping list once you have your modified spark plug in hand.

About ready to preform procedure. Still need to remove Saf-Air drain, and install funnel to catch solvent from drain hole.

Top of piston at right, oil on bottom of cylinder wall.