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YIO-540 and Lycoming Service Instruction for Constand Speed

YES. You need to remove the plug. Look down the crankshaft, you'll see the plug. Leave it in only if you are not using a cs prop.
 
I am not familiar with your specific engine but its unlikely your not already set up for constant speed. Simply make sure the expansion plug is not at the crankshaft flange and that the internal plug about 6 inches back is and that the one 6 inches back has no holes in it. If so you should be good to go.
Ryan
 
Our YIO-540 from Lycoming through Vans came setup for a C/S prop configuration. We just had to remove a big red plastic plug from the front of the crankshaft and that was it, but definitely be sure to check!
 
Interesting. My YIO-540 also was ordered thru Vans but it came with the internal plug! I guess you have to look!!
 
Hmm, I'm a little confused and hope I didn't screw something up. In my YIO there is a metal plug about 1" back from the front of the crankshack. It is a bear to try to get out. I had read somewhere that you need to drill a hole and use a screw to get this out, but it just doesn't seem to budge at all.

I'm begining to wonder if I drilled the wrong thing and screwed something up. Is the plug difficult to remove?
 
Ok, I did some more research and saw I was indeed working away on the right plug. So I enlarged my hole a little larger (3/8") and then use a metric allen wrench of considerable size that never gets used for anything. Several hard smacks on it while pinned inside the hole and it finally popped out. It took quite a bit of muscle to get it to pop out.

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So, for future reference, the easier way is to find a hardware store lag bolt of the right length; drill a thru hole in a substantial piece of wood, large enough to span the crankshaft. Put the bolt thru the wood, start it in the small hole you drilled in the plug. As you tighten the bolt, the plug will come out.
 
I believe so. There is a similar metal wall/plug about 2-3" behind then return tube (crosses side to side with a cutout).
 
Internal metal ply on IO540 for Constant Speed Prop

Bob Turner's method is absolutely the way to go!. Do not start banging on the plug to somehow pop it out. Drill a 1/4" hole in the plug center just enough to create a pilot hole for a 3/8" x 3" lag bolt. Just get a simple galvanized lag bolt from hardware store that is inserted through a 2x4 big enough to bridge across the opening diameter (3" or more is enough) and is pre-drilled with a 3/8" hole in the center. You just don't want the threads catching on the wood inner diameter. Use a 3/8" flat washer under the head of the bolt and place the 2x4 surface against the flange. Begin tightening the lag bolt into the pilot hole and be sure have something ready to catch the oil that most likely will come dripping out (unless you like clean up oil puddles like I had on my floor). BTW it's probably smart to vacuum the external metal shavings from the drilled hole before removing the plug to limit the amount that could get into the opening. You'll want to wipe away any shavings to keep them out of your oil system. If I knew what I was doing I'd attach photos, but it is pretty straight forward after you decide to do it this way!
 
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