0-320 crankshaft part numbers, superceded list. Educate me please.

[terry.mortimore]

Hi gang:

Here's my situation, I'm trying to accumulate enough parts to build up a 150 hp fixed pitch IO-320.

I have a narrow deck crankcase that has been overhauled and had the mounts changed to dynafocal.

I need a crankshaft to go along with it.

So here's my question. My April 1970 parts catalog lists a crankshaft 75010 part number, is this still a valid part number? Or has it been superseded? If it has, where can a fellow go to find the current number?

Since I have not purchased my prop yet, I'm not concerned about the type of flange needed. Will any of the 0-320 crankshafts work for me?

Thanks in advance for your help, Terry

[jrs14855]

There are hollow shafts for constant speed, solid shaft for aerobatic aircraft(not constant speed compatable), flanges with and without lightening holes. There are supposedly thicker flanges for aerobatics. Otherwise, leaving out the H models, as far as I can determine, any crank will fit any case. I am going the same route as you, I have a junk crank with lightening holes and a good crank without and as far as I can determine they are both the same except for lightening holes. Both flanges are the same thickness. It appears that different bushing configurations produce different crank "assembly" numbers but I'm not absolutely certain about that. You could post on yahoo/lycoming and maybe Mahlon would respond, or you could contact him directly at Mattituck. Good Luck, Jim

[terry.mortimore]

Hi Jim, thanks for the reply.

That's what I wanted to hear. You mention prop flanges with lightening holes, I'm wondering if it would be wise to use a prop extension with these types of cranks?


tailwinds, terry.

[rocketbob]

Get the latest parts manual for your engine from Lycoming. It will have a list of superceded part # and what the current part #'s are.

The latest cranks are the heavy-flange, so make sure if you're buying a crank outright it is one of those.