opinion of the best engine conversion

How to keep the Cessna 170 flying and airworthy.

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punkin170b
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Post by punkin170b »

Well I'd probably go with the Lycoming now, too, since what I am learning (Thanks George! :D Ignorance was bliss! :? ) and verifying about PZL/Franklin has "come to light". I guess I'll just hope real hard that my experience with our conversion continues to be a good one, and that I don't end up in deep caca over parts. Maybe in 10 years when we reach TBO somebody will have begun producing these great engines again...
Matt
"Rule books are paper. They will not cushion a sudden meeting of stone and metal." (E.K. Gann)
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ak2711c
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Post by ak2711c »

I heard rummor that ECI was working on manufacturing replacement parts for Franklin's, and was negotiating with P&W to buy the rights to the 220 Franklin with hopes of putting it back into production. Like I say just rummor, I don't know if there is any truth to it. Maybe just wishfull thinking.
Shawn
punkin170b
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Post by punkin170b »

(See below)
Last edited by punkin170b on Mon Aug 30, 2004 2:41 pm, edited 1 time in total.
"Rule books are paper. They will not cushion a sudden meeting of stone and metal." (E.K. Gann)
punkin170b
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Post by punkin170b »

Yep, my research has also lead me to discover that ECI "rumor" as well (via a phone conversation last night). The fellow who did all the knitty grittys on our engine conversion has (had?) a good rapport with the Ft Collins Franklin guys and is going to try to make contact with them for some updated info. All we Franklin operators oughtta start hounding ECI and encouraging such a deal... http://www.eci2fly.com/
Matt
"Rule books are paper. They will not cushion a sudden meeting of stone and metal." (E.K. Gann)
N1277D
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Re: Franklin Engine Parts

Post by N1277D »

ECI does make Franklin engine parts but will not sell them retail. They produce them for A-1 Services in Texas. A-1 has or is working to produce most Franklin Engine parts.
punkin170b
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Post by punkin170b »

Now we're getting somewhere... I found a page on ECI's website listing some Franklin replacement parts... http://www.eci2fly.com/Products/franklin.htm
77D, do you have any more info on A-1 Services? My Google Search is coming up dry. Thanks for the encouraging info.
Matt
"Rule books are paper. They will not cushion a sudden meeting of stone and metal." (E.K. Gann)
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GAHorn
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Post by GAHorn »

Dave Clark wrote:Thanks Mike.

Your turn George. :P
Ha! I really don't have a dog in this fight. (Mine's installed in my cowling!) :wink:

I'd bet dollars to dough-nuts that Mike's experience running Lyc's "to tbo" without cylinder changes is no different than most of us, and probably not exactly correct.
Mike....I'm not trying to be disparaging nor accusative here (I'm trying instead to be especially accurate) but exactly how many Lyc's have you personally run from zero all the way to tbo? (Or perhaps like most of us you've operated a few Lyc's that were near or past tbo that others have run and maintained, and in fact you actually never did a complete log-book research of their maintenance history...but like most of us, instead merely took someone else's word regarding the particular engine's history?)
It is rare indeed for any engine, TCM or LYC to run from zero all the way to TBO without some sort of engine cylinder maintenance. Most of us actully come across an airplane (or engine) that is already mid-life or part-life, and we operate it a few or a few hundred hours....have a good experience with it...and later our memories of that experience cause us to pronounce it a "great" engine or a "sorry" engine. Few of us actually take a new/zero engine and operate it all the way through it's tbo service life and have intimate knowlege of that particular engine's service history. (And even if we did, that would only be one engine...out of thousands. Hardly a scientific study of an entire engine line versus any other.)
This sort of opinion-statement is called an "anecdote". Anecdotal commentary is a hazardous thing. It's what causes arguments at the Wal Mart automotive section about which is the best motor oil, even though 98% of the plastic bottles contain the same product. (That 98% is an anecdote) :wink:
Trivia question: Anyone care to guess which general aviation reciprocating engine has the best all-time TBMF (Time Between Mean Failure) rates in single engine airplanes?
Hint: It was factory installation in over 13,000 Cessnas. (NOT an anecdote.) :wink:
Last edited by GAHorn on Mon Aug 30, 2004 4:27 pm, edited 1 time in total.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
punkin170b
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Post by punkin170b »

Hey George - a wild guess, but how about the Continental IO-520D? What a great, smooth running engine that is. Love 'em in 185s and 206s. Wish I could fit one on Punkin (hehehe).

Even though I have become more of a Continental (and Franklin obviously) fan, I have a first hand story about the Lycoming O-360. My dad paired one with a Hartzell CS prop and installed it on his 1972 Ce172L back in the early 80s. He is at TBO this year, and his last annual forced him to replace his first piston ring. Still all original jugs, pistons, valves, pushrods etc, etc. I hope I haven't jinxed him here, but he's had great luck with his engine. He does take extremely good care of it, and does not run it very hard though. My only complaint is that it just doesn't run smoothly like a 6. Dad marvels at the performance and smoothness of my li'l Franklin 220 powered 170. Now if I could only get him to marvel at the pilot! (Never gonna happen!)

Matt
"Rule books are paper. They will not cushion a sudden meeting of stone and metal." (E.K. Gann)
mvivion
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Post by mvivion »

George,

From one of your posts:

"The Lycoming has a nasty history of poor valve lubrication, galled cams, failed oil pumps, broken cranks, and vibration problems."

Let's see, is that direct operating experience, or hearsay? If it's evidence of a failure on Lycoming's part, let's hear the specific evidence, George. Where are the scientific studies and/or FAA/NTSB data to support your assertion?

There's no question that the Lycoming's camshaft can be spalled on engines that see a lot of non use. But, that's easy to fix: Fly it, don't park it. Leave it sit in it's tiedown for two years without firing it up, and you'll have a problem sooner or later. Unfortunately, that's a common occurance with aircraft just prior to sale--non-use, so the next guy has a spalled cam. Maybe he didn't read the logs. I do.

As to broken crankshafts, my personal observation is that I personally know three folks who've had crankshaft failures with Continentals (I am one of them). I have NEVER heard of a crankshaft failure IN A FOUR CYLINDER Lycoming. That's not to suggest that this has not occured, but I would suggest that maybe you are extrapolating six cylinder engine data over to fours, and it doesn't translate. Further, the crankshaft failure rate on Lycomings and Continentals is about the same, when it comes to six cylinder engines. That is based on verbal discussions with both Lycoming and Continental tech reps. Note in the latest round of crankshaft failures that both companies got their crankshaft blanks from the same foundry. Also note that not a single one of these crank failures was on a four cylinder engine.

As to 360's, I've never personally run one to tbo, from start to finish, with me as the only pilot. I've put a lot of hours on both O360s and O320s, though, including running one 320 from 0 to 2200 hours. I wasn't the only pilot of that aircraft, but I guarantee you that no cylinders were changed on it. I've also run at least two 360's to over 1300 hours, and happen to know that at least one of those engines subsequently went to tbo, and no cylinders were changed.

So, George, what is your specific PERSONAL experience with Lycoming four cylinder engines using up cylinders and breaking crankshafts? No opinions, or hearsay here, mind you--your direct operating experience, upon which you based your previous post.

It is worthy of note that when Lycoming overhauls, or remanufactures an engine, they remove and replace the cylinder assemblies, and do not reuse any parts from them. Continental, on the other hand, ascribes to the FAA approved philosophy that any part that meets service limits can be put back in an overhauled engine, even if it is worn to very near service limits. Continental, in their factory overhauls, are a bit more conservative than that, but they do reuse a lot of used top end parts in overhauled engines.

Lycoming says that one of the reasons that folks see a fair amount of valve train problems and other top end problems is that they are re-using cylinders, and other top end parts. Lycoming says don't do that, and their service history suggests that they are right WITH FACTORY engines.

I agree with you that the O-470 Continental is probably the best engine Continental ever built. That said, I wouldn't trade any Lycoming for any Continental, and I've owned and operated both for years, and thousands of hours. That, I want to specifically note, is my personal opinion, and is not endorsed by either engine manufacturer.

We all have different experiences. Each has value. I simply offered my experiences for what they are worth. If you don't agree, that's fine.

As the old saying goes: we all have opinions, *** And that's all I've got to say about opinions.


Mike
zero.one.victor
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Post by zero.one.victor »

xx
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GAHorn
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Post by GAHorn »

Well Guys, I certainly didn't intend this to be a personal attack vs retort type of discussion...and I hope it's not anyone else's intent either. :?
This is classic Ford vs Chevy, and the fact is both mfr's have strong as well as weak points. If the question in this thread regards the asking of opinion, then there's no reason to attack someone for expressing theirs, nor any reason to develop animosity for an opposing viewpoint. Right?
As for crank failures, no I've not personally experienced one in either TCM OR LYC engines. I have personally experienced lots more valve problems in LYCs of all numbers of cylinders, tho', than I have in TCMs.
As for the resource info on my prior statement, I'll post it again, although it's been posted before:
http://www.prime-mover.org/Engines/Marvel/tbo3.html
This is one of the better studies I've seen regarding the inferior LYC engineering regarding valve trains.
As for the crankshaft failures, perhaps you didn't know about the AD notes regarding 4-cylinder hollow cranks? I thought it was pretty well known. Perhaps you've merely forgotten.
I agree with you Mike, that it's admirable that LYC insists on their overhauls using only NEW cylinders. But that policy is also the very reason an apples-to-apples comparison is so difficult when comparing to TCMs......so many TCM cylinders actually ARE reused. (But then folks complain and wonder why their TCM needed a TOP....and then they praise the LYCs for lasting longer! Not exactly accurate comparisons or fair even, heh?) And BTW, ....it is inaccurate to refer to TCM factory overhauls on the C145/O-300 because the factory does not perform overhauls on this engine.
Anyway,....as for opinions....you're absolutely correct that they're merely that...opinions. I hope we don't find differences of opinion to be reasons for adversarial positions that become public disagreements.
I know that's not my intention anyway. (Pardon my cleaning up of a phrase I felt offensive. I don't believe it changed your msg.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Post by Bruce Fenstermacher »

George I'm not getting into this "discussion" except to say that the AD on the hollow crank 4 cyl. lycomings is a bunch of FAA BS based on 2 crank faliers which happened outside the US on aircraft with very questionable history and maintenance.

Even the FAA backed down on the original AD which was to cover all 0320 and 0360 engines without a constanst speed prop. The voice and economic impact of thousands of these engines and their owners was to much.

So the FAA narrowed the effected engine to those of 160 hp and more which eliminated all the 0320 150 hp engines which was the majority. Now the economic impact and voice of the owners was small enough and the AD went through. Never mind the 0320 150hp has exactly the same crank as the 160 hp model. And I believe one of the failed engine was 150hp. I know, I owned one which was 150 but upgraded to 160hp with new pistons at rebuild.

BTW I went with a Briggs & Straton in the motorized version of my airplane peddle car pictured below. Bet that will get the Tecumseh boys riled up. 8)
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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