Lycoming O-340 Engine

[Blue4]

Greetings, All. I want to buy a 170, and I will soon be looking at a 1953 170B. It has a Lycoming O-340 engine (170 hp) with a constant speed prop.

No one I know has experience with this motor (and neither do I). Apparently the 170 was one of the few applications it was approved for. I've learned that its essentially a modified O-320. What would you, the community, recommend?

Will I experience difficulty in locating parts, or in finding someone to work on the motor? Any reliability issues? Common problems?

Thanks in advance ... happy skies and tailwinds.
-Scott

[ronjenx]

A google search brought up several good links on the O-340, including history and a parts catalog.

[Blue4]

Google answers all questions ... almost. I'm hoping some of the members out there have experience.

The airplane I'm looking at has a low-time O-340, so it would probably be a while before overhaul. I'm just concerned something like a magneto or jug would need replacement with no obtainable option.
-S

[Blue4]

My partner found this on the forum.

http://www.cessna170.org/forums/viewtop ... 36&start=0

Apparently his use of the search function is better than mine. I couldn't find ANYTHING.

[GAHorn]

My partner found this on the forum.

http://www.cessna170.org/forums/viewtop ... 36&start=0

Apparently his use of the search function is better than mine. I couldn't find ANYTHING.

The lack of responses in this thread is indicative of a lack of information, rather than a lack of enthusiasm for helping a fellow. Sorry not to have been more informative.

At the "Twin Navion" site, the following is stated:
" The Lycoming O-340-A1A engines are the only down fall of the D-16A. They're an odd-ball, built in low numbers before the O-360 started. That's not to say they're bad. No. It does mean that you should keep your eyes and ears open for parts though. In the last ten years, we've picked up three spare engines. One from an STC'd Cessna 170 that the owner was changing to an O-360, and two from an STC'd Apache that was being parted out. In both cases the owners asked our local engine shop if they knew anyone interested, and they passed the word to us. I won't tell you what we paid, but all three were less than an overhaul. Many people are scared away because they think its impossible to get parts. Its not impossible, you just need forward thinking."

[Bruce Fenstermacher]

A friend of mine has an O-340 in his Beech Musketeer (? It's definitely a Beech Craft 4 seat anyway). They are the only airplane I've ever heard that had then from the factory but I'm certainly no authority.

My friend had his overhauled about 3 years ago and found it took time to find the parts but Mattituck eventually came through.

I just got off the phone with my other friend who works in the tech support department at Lycoming. He said what has already been said. Very few were ever made, Beech was the only one to use them and parts are hard to come by. He said Lycoming does not support the engine with any parts any more so any new parts would be from someone else or new old stock.

My suggestion is to look at the STC that allowed the 0-340. Does it also allow an 0-360 or less desirable an 0-320? If so your repair/overhaul path would be to swap out to one of those engines if parts can't be found for the 0-340.

[Roesbery]

A friend and I were looking into this engine as a possibility for his Cub. Anyway this seems to be the most informative site found so far http://en.wikipedia.org/wiki/Lycoming_engines You can get the history and the differences between the O320 to the IO390 four cylinder engines

[GAHorn]

That link appears to be broken. Here's one that discusses the O-340 specifically:
http://en.wikipedia.org/wiki/Lycoming_O-340

Apparently, the 170 h.p. version of the engine requires a minimum of 91/96 octane avgas.

[Watkinsnv]

You will find that the Lyc O-340 is the least of your problems. That C/S prop has an AD on it that makes it useless. And its the only C/S prop authorized for that engine. Watkinsnv

[Jr.CubBuilder]

You might check with CubCrafters and/or ECI on the 180hp O340 that they are putting in the Super Sport Cub. I don't know anything about it but it may be based on the old Lyc. 340 and there might be parts compatibility from ECI.

[Bruce Fenstermacher]

I just spoke with my contact at Lycoming tech support. The CubCrafters CC340 has nothing to do with Lycoming. Except of course that all the parts made by ECI and this engine are probably direct copies of a Lycoming engine and it's parts. My contact knew nothing of this engine until I showed him CubCrafters web site so who knows what if anything anyone at Lycoming knows about it. (Can you smell law suit here)

Could be that ECI is making exact 0-340 parts and using them on the CC340 and they have a PMA which would allow there use on 0-340.

[Jr.CubBuilder]

That's what I was thinking, but as long as they are PMA'd for the original O340 you could legally source them for parts right?

I'm guessing they make the extra ten ponies with some induction improvements and most likely spinning it a bit faster.

[Bruce Fenstermacher]

Interesting that the CC340 is rated at 180 HP for take of only and only 80 HP at cruise according to very sketchy information on the CubCrafters site.

If ECI has a PMA for any of these parts to be use on a Lycoming 0-340 then any of them could be used with no problem. Bet ECI doesn't have such a PMA because that would only add fuel to any Lycoming law suit.

[Jr.CubBuilder]

But I don't think Lyc. would really have a leg to stand on since they don't currently produce the motor. Oh well it's interesting at any rate, I wish both Lyc. and ECI the best since I've got goth companies parts in my plane.

[Brad Brady]

Interesting that the CC340 is rated at 180 HP for take of only and only 80 HP at cruise according to very sketchy information on the CubCrafters site.

If ECI has a PMA for any of these parts to be use on a Lycoming 0-340 then any of them could be used with no problem. Bet ECI doesn't have such a PMA because that would only add fuel to any Lycoming law suit.

Bruce,
The rated HP probably has something to do with the Prop usable.....Dont you think?......Brad