What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

removing the front crank plug?

R

Ron B.

Well Known Member
I have searched this forum but was not able to find the proper way to remove the front crank plug for constant speed prop. I have a new Lycoming IO-390 with the supplied manuals and all I can find is it needs to be removed.
I recall mention of drilling a small hole in the center and securing a small bolt or screw and pull on that. I'm not liking drilling due to the chips. Tapping or applying a screw will make more.
I also recall or at least I think I recall someone mentioning using the ball side of a hammer and hitting the hammer with another , caving in the plug loosening it. How solid is this plug? Is it like a frost plug on industrial engines, if so I do believe that is how they are removed.
Thanks Ron
 
Not a real issue for removal.

IIRC, I started with a 3/16" drill bit and made a good dent, removed the chips then drove an awl for the hole for a #8 screw on the end of a slide hammer. It was too thick for just hammering in the awl. I had the bright idea of doing it off center to have it come out easier, but it should be in the center. A few whacks and it comes right out. If off center it will get sideways and harder to remove. It is a big hole and crappy oil from the first run. Catch it and then clean out the bore.

No problem.
 
Use a sharp punch and poke a 1/4" or so hole a little off center. Do not run the punch much past the seal. The seal will come out easily with a screwdriver or such using the hole as a leverage point.

Carl
 
Crank plug

I have removed and installed many of these. Easiest way by far to remove is with a slide hammer. Drill hole almost all the way thru plug, stop and put a dab of grease on bit and drill thru. If drilling hole leaves any chips behind they will be right up front and easy to reach and remove.

Don Broussard

RV 9 rebuild in progress
 
I just removed mine using the large BallPeen hammer end. I put the rounded end of the BallPeen hammer in he middle of the plug and hit the other side with a dead blow hammer. I started hitting it like a girl and ended up giving it a couple of good whacks until the outie became an innie. I then pulled it out with a magnet, it was too easy and took way less than 5 minutes.
 
Had to do this recently on my IO-540 after it came back from the rebuild shop (they plug it to do the initial engine run). The local AME told me to take a punch and a 4# hammer and give it a few solid blows. Took about 4 whacks and it was loose - no chips from drilling...........

Just felt kind of weird hitting anything on my airplane with a hammer!
 
I was surprised how easily the plug came out using a slide hammer. Effortless.

cajunwings said:
I have removed and installed many of these. Easiest way by far to remove is with a slide hammer. Drill hole almost all the way thru plug, stop and put a dab of grease on bit and drill thru. If drilling hole leaves any chips behind they will be right up front and easy to reach and remove.

Don Broussard

RV 9 rebuild in progress
Click to expand...
 
Ron B. said:
I have searched this forum but was not able to find the proper way to remove the front crank plug for constant speed prop. I have a new Lycoming IO-390 with the supplied manuals and all I can find is it needs to be removed.
I recall mention of drilling a small hole in the center and securing a small bolt or screw and pull on that. I'm not liking drilling due to the chips. Tapping or applying a screw will make more.
I also recall or at least I think I recall someone mentioning using the ball side of a hammer and hitting the hammer with another , caving in the plug loosening it. How solid is this plug? Is it like a frost plug on industrial engines, if so I do believe that is how they are removed.
Thanks Ron
Click to expand...

Yes it is like a Soft Plug in other engines. It is NOT very thick.

The hammer method you describe is how I was told to do it back when I was in A&P school over 20-years ago. It works faster and easier than any other method others have told you to use.
 
Thanks for all the replies. I drilled a 1/4" hole and used a self taping screw welded to my slide puller but it stripped right out. I had to enlarge it to a 3/8" lag screw. That worked but there was some resistance .
Ron
 
You must log in or register to reply here.
Back
Top