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In my continuing to search for the oil pressure dropping 215 to 20 pounds doing flight I'm trying to remove the oil plungers. Any suggestions how to get the actual plunger out of the case? The plugs and springs came out with no problem but both the plungers are not moving.

caymancraig wrote:In my continuing to search for the oil pressure dropping 215 to 20 pounds doing flight I'm trying to remove the oil plungers. Any suggestions how to get the actual plunger out of the case? The plugs and springs came out with no problem but both the plungers are not moving.

Craig,

Did you mean to type 215 lbs? Or did you mean 115 lbs? If you are getting a reading of 215 lbs on your gauge I'm pretty sure it's a gauge problem!

Wrote that wrong It drops to 15-20 lbs after 10 minutes of flight. Same both flights

Well, I got them out. I put the plug back in and started the engine for a minute and then remove the plugs and they fell down right on top of the plugs. I had each of them in the rifle. They do seem a little tight pushed in all the way so I'm going to get them with a emery cloth and smooth them up.

To get out a sticky plunger I had, I used a length wooden dowel (I believe it was 1/2" diameter or so), cut a split in the tip, and inserted a little piece of shim into the cut. I pressed the dowel up into the bottom of the plunger, then gave it a couple light whacks with a mallet. This drove the shim piece into the cut of the dowel, creating outwards pressure that locked the dowel into the plunger.

Plunger came out with a tug. I was able to work the plunger full length to see where it was grabbing, cleaned/sanded it up a bit, pulled the dowel out of the plunger and reassembled.

Ryan, I'm the owner of Sonex #371 here in Appleton, WI. I do not understand what you are referring to in removing the "oil plunger". What is and where is the "oil plunger?"
Thanks, Ed Perkins

Ed Perkins wrote:Ryan, I'm the owner of Sonex #371 here in Appleton, WI. I do not understand what you are referring to in removing the "oil plunger". What is and where is the "oil plunger?"
Thanks, Ed Perkins

In the Aerovee Engine, there are 2 oil control valves. The valves are controlled by spring pressure and a metal plunger (or piston if you will.) Basically when oil pressure gets high enough, the oil pressure pushes against the spring pressure and a valve opens, allowing oil pressure to bypass.

They look kind of like this:



A stuck plunger can cause high/low oil pressure issues.

Here are some pics of my dowel plunger removal method that I described above:

I also had to remove mine recently and removed the spring, put the cap back on and started the engine. The plungers fell right to the bottom.

I also hear a magnet pulls them right out (according to a VW forum I searched on).

If you are running low pressure, you may want to consider looking at this:
http://chircoestore.com/oil-pressure-ad ... ngine.html

I heard it works well. I have one but haven't completed my first flight so I don't know if it is needed or not.