The International Cessna^® 170 Association

Wondering about putting an 0-300D crank in my 300A

Thank you! I literally read through posts for a couple hours and never found that one.

Yes, Continental has a SB that describes how you would go about installing a D crank and changing the engine to a D from an A. It's posted here but I haven't the time to find it at the moment.

Heflin, I have a copy of the STC that allows the O-300-D crank in the O-300-A case I can send you. I don't know how to post it here as copy and paste does not work. I don't get here often so send me a email at Ron (N#) at aol dot com. It also uses the angel drive starter and vacuum pump accessory. You will still need the O-300-D STC for prop approval since it switches to a 6 bolt prop flange. Ron

Full disclosure on what Ron has unless he has more than I know.

The STC Ron speaks of is owned by an individual perhaps now deceased. TIC170A does not own it. This individual made it known to Ron that he wanted the STC to be in the public domain. In other words anyone and everyone has permission to use it. Unfortunately Ron does not have that permission on paper.

The Feds require paperwork submitted for STCs today to have a serialized permission document from the owner. You will likely run into a problem without one when the paperwork is submitted. This is a case of someone wanting to do the right thing with his STC but not doing it in a legal fashion the Feds will accept. I wonder if the Feds will even accept a STC in the public domain? Who would keep track of the paperwork we are required to keep?

The way I see it, all the parts in the c-145/0-300 should be able to be used regardless of the actual engine model. They all fit and they all work together. Continental considers some of them superseded parts for the old. Many an engine has mixed parts with one time approvals. This guy got an STC to do it which actually muddies the water today. But there should be NO reason a reasonable person or Administration should think mixing the parts shouldn't be done. But then we know the FAA is not the most reasonable in most cases.

As Ron states, once you get over the hurdle of an engine with mixed parts, hopefully if you have a 6 bolt crank, you also call this engine a C or D and change the data plate to reflect that (see the SB). Then the Associations STC will make the prop you need and the installation of this C or D legal to install on a 170.

Thanks guys.

Heflin, STC SE4728NM by James W. Johnson in Spanaway, WA. is the holder. You can find him via phone. Ron

I a mistaken his STC is putting a "A" crank in a "D" engine and using it to drive the angle drive starter and vacuum pump-not the way you want MY opinion is if you put the "D" or "C" crank (which is the same). You are actually converting an"A" engine to a "C" by Continentals policy if you use the same starter system. Or to a "D" if you switch to the angle drive starter and vacuum pump system O-300-ACC stencil or O-300-ACD. Maybe J Wildharber might step in here- he put an "A" crank in his engine and driving the vacuum pump and starter like the "D"( I think that is right????). If you convert to a "C" you would need the SA7441SW STC that allows the use of the 6 bolt prop. Ron