Some Engine Questions

Ok, so I admit that I'm a complete novice in terms of aircraft engines.

It seems as though my budget may prevent me from initially putting a C/S on the nose of my aircraft. I'm considering a Sensenich or Catto and then later upgrading to a C/S.

1) I understand that I can get a hollow-crank engine, plug it and put a FP on the nose, but are there any caveats to doing so?

2) If there is no caveat, then why aren't ALL aircraft engines setup for C/S and plugged?

3) For those that have done it, is the upgrade difficult?

Hollow crank

Depending on the original application intended for manufacturing the engine, it may require a hollow or solid crank. The factory makes that choice.
As to plugging your crank, it's a simple process of installing a "freeze" plug and simply plugging up the hole. You can get the plug from Lyc. ot any auto parts supplier. Have done many.
If you don't yet have the engine, and you find one with a solid crank, an electric C/S prop can be mounted.
T88

Lycoming Service Instruction 1435 details the procedure for converting between fixed pitch to constant speed and vice a versa.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at you own risk."

In about a month, I should be taking delivery of my Mattituck IO-360 with the hollow crank (for CS prop) but set up to run a FP prop (Catto 3-blade).

I will happily be running the Catto FP prop, but I ordered the engine the way I did in order to have the option option later to change to CS if the "need" just hits me. Plus, at my age, this aircraft will probably be up for sale in a few short years so I figure having the engine configured to (easily) take a CS prop would be a great selling point.

If you're buying a brand new engine, even if you intend to use a FP prop, get it built with the hollow crank because that way, you or a subsequent owner will always have the option to change over without overhauling the engine. Mahlon is the guy to talk to about that because he's the one who walked me through it when I made my order with Mattituck.

And by the way Mahlon, Brad at Emag told me yesterday (3/28/06) that he was shipping the Pmags this week so you should have them in the next few days.

More info

Some engines are not set up because when Cessna or Pipe "specs" an engine and says fixed, Lycoming can save a few pennys by not having to drill and tap some holes, make room for a prop gov on the assccory case and do more machine work on the crank (hallow crank).

Now when buying a used engine, especially if on a budget you may get what you can get. You would be happey either way. If you are on a budget you would be going Fixed anyway.

However if buying a new clone you might as well pop for the extra $500 for the c/s version, even if you don't use it. It will be there when and if you want to go C/S. If you absolutly know you will never need or want a c/s prop than get the fixed version, however on resell the c/s capability will add value.

The biggest caveat about making an engine meant for C/S usable for fixed is, make sure the plug in the crank is driven fully into the crank. Many car engines have what is called a "freeze out plug". It is a big round flat plug with a flange pressed into the engine block. The idea is if the water freezes the plug pops out and saves the block from craking, in theory.

The hollow crank plug is like the FOP and has an interference fit, so it must be driven in with a big-A mallet.

FAILURE TO SET THE PLUG CAN RESULT IN LOSS OF PLUG AND ALL OIL OUT OF THE ENGINE, WHICH WILL END UP ALL OVER THE WINDSCREEN. IT HAS HAPPENED BEFORE.

G