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Lycoming case splitting tool

gladiator68

Active Member
Sponsor
I am just reaching out to see if anyone has the "right" tool to split a Lycoming case. I was beginning my reassembly and something isn't right on the front main so the crank is tight.

Does anyone have this tool they would be willing to rent? I'd pay shipping both ways. Don't think my local chapter has one. There is one for $1k from Ryan but that is pretty steep unless I can share/sell it.

Worst case I can build one, but don't want to damage anything along the way...

Thanks.
 
You've pulled the long through studs, correct? They come out easily with a slide hammer and usually the case will pop apart with a few dead blow taps. Keave them in and it can be nearly impossible to split the case.
 
When I split mi IO-540V4A5 case, I managed to get the thru bolts out pretty easily using a combination method of adding a 3/8" X 2" steel load spreading spacer bar on one side and adding washers under the nuts as I tightened. Run out of thread, add more spacer washers under the nuts. When they were mostly out, I finished it up from the other end of the thru bolts with a special sacrificial cap nut and a pneumatic impact hammer. Once the thru bolts are out, the case splits pretty easily using a composite dead blow hammer and a heavy duty putty knife.

Now my buddy brought his IO-540 over to my shop to rebuild it and we quickly discovered that his thru bolts were screwed in, not press fit as we expected. They came out using an Allen wrench inserted in one end of the end of the thru bolts and unscrewing them.
I don't recall which model 540 he had, nor which Lycoming engines used those screw in thru bolts. He put that beast in the Cozy MKIV he's building. :eek:
 
When I split mi IO-540V4A5 case, I managed to get the thru bolts out pretty easily using a combination method of adding a 3/8" X 2" steel load spreading spacer bar on one side and adding washers under the nuts as I tightened. Run out of thread, add more spacer washers under the nuts. When they were mostly out, I finished it up from the other end of the thru bolts with a special sacrificial cap nut and a pneumatic impact hammer. Once the thru bolts are out, the case splits pretty easily using a composite dead blow hammer and a heavy duty putty knife.

Now my buddy brought his IO-540 over to my shop to rebuild it and we quickly discovered that his thru bolts were screwed in, not press fit as we expected. They came out using an Allen wrench inserted in one end of the end of the thru bolts and unscrewing them.
I don't recall which model 540 he had, nor which Lycoming engines used those screw in thru bolts. He put that beast in the Cozy MKIV he's building. :eek:

Pretty sure most, if not all, narrow decks use through bolts that thread into the left side of the case. Unsure if any wide decks use this method.
 
splitting case

Here is a pdf of my 0320 narrow deck when i overhauled it. A few slides of the splitting of the case.

dl=0"]http://https://www.dropbox.com/s/n8h778nxn0pdsjo/o320%20ohaul%20copy.pdf?dl=0[/URL][/URL]

Keith Rhea

RV7

Donated '21.
 
Here is a pdf of my 0320 narrow deck when i overhauled it. A few slides of the splitting of the case.

dl=0"]http://https://www.dropbox.com/s/n8h778nxn0pdsjo/o320%20ohaul%20copy.pdf?dl=0[/URL][/URL]

Keith Rhea

RV7

Donated '21.

Very cool Keith. I absolutely love watching engines being overhauled.
 
Here is a pdf of my 0320 narrow deck when i overhauled it. A few slides of the splitting of the case.

dl=0"]http://https://www.dropbox.com/s/n8h778nxn0pdsjo/o320%20ohaul%20copy.pdf?dl=0[/URL][/URL]

Keith Rhea

RV7

Donated '21.
Thanks Keith!
I see what is going on now.
My case has threaded studs as well (0-320 D2B oldie) so can't take them out.
Thanks again!
 
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