Cessna 175

Tom-D

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Tom-D
Who holds the engine up grade STC for the TCM IO-360
 
Rich Barclay maybe? A googling of "c175 io-360" turned up cessna175.org which seems to be active. His name came up in there having it a few years ago.
 
Someone in Alaska was working on a O-390 stc.. simpler, more power...
The Lycoming O-360 or IO-360 is a much better choice than the TCM IO-360. lighter, two less jugs to feed and maintain..
- I had a 1960 175 with the O-360 and CS prop, fantastic machine.
 
Who holds the engine up grade STC for the TCM IO-360

image.jpg
 
STCNumber=SA3890NM TCNumber=3A17>
Manufacturer CESSNA MakeModel 175
TCNumber 3A17 Description Installation of a Continental IO-360-C
engine, McCauley D2A34C propeller and associated accessories. Status
Amended 10/16/96 ACO NM-D

STCHolder Richard W Barclay & Dana L. Barclay
10808 Snow Cloud Trail
Littleton COLORADO 80125 UNITED STATES

TCM IO-360 is supposed to be lighter than the GO-300. My guess is the Lyc IO-390 is heavier. Pretty much the same engine as my exp IO-400. No question mine's bigger and heavier than an O-360 (angle valve vs parallel valve).
 
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STCNumber=SA3890NM TCNumber=3A17>
Manufacturer CESSNA MakeModel 175
TCNumber 3A17 Description Installation of a Continental IO-360-C
engine, McCauley D2A34C propeller and associated accessories. Status
Amended 10/16/96 ACO NM-D

STCHolder Richard W Barclay & Dana L. Barclay
10808 Snow Cloud Trail
Littleton COLORADO 80125 UNITED STATES

TCM IO-360 is supposed to be lighter than the GO-300. My guess is the Lyc IO-390 is heavier. Pretty much the same engine as my exp IO-400. No question mine's bigger and heavier than an O-360 (angle valve vs parallel valve).
Thanks for that,, I'm trying to rationalize up-grading a 175 that really is a nice aircraft and can be bought for less than 20k, but the engine has a bad gear box.
 
I sure enjoyed my Hawk XP and it's IO-360KB. That 175 converted would be an equal performer. Good airplanes.
 
Isn't there an STC for an O-470 in the 175?
 
So would the replacement just eliminate the gearbox and be a "conventional" Cessna 17X?

Is the 175 a different airframe than a 172 or 177?
 
So would the replacement just eliminate the gearbox and be a "conventional" Cessna 17X?

Is the 175 a different airframe than a 172 or 177?
It is a different type certificate the 0-300 is not an alternate engine.
I've tried twice to contact the holder of the STC for the IO-360-C into the 175-A but they don't answer the phone.
 
Pretty sure my friend has an O-360 in his. It makes it a very nice airplane.
25963387571_d1d64a37e8_b.jpg
 
Pretty sure my friend has an O-360 in his. It makes it a very nice airplane.
25963387571_d1d64a37e8_b.jpg
They are nice aircraft with the 180 horse Lycoming. But... the cost of a Lycoming 0-360 is twice the price of a IO_360, as is the costs of the STC. and the IO-360 can be a 210 horse.
There is also a STC to install the 220 horse PZL Franklin.
 
Is the 175 a different airframe than a 172 or 177?
The 175 looks just like the early 172 in the wings, tail and fuselage from the doors aft, but the structure is beefed up some. The forward fuselage, instrument panel area, windshield, firewall and cowl are all very different.

The 177 (Cardinal) is 100% different -- no common parts with 172 or 175.
 

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I have a 1960 175A that has had the geared GO-300 replaced with an O-320 off an Apache in 1965. It has the Constant speed prop as well. It is a very good performer despite the lower horsepower (160 vs 175). The STC may or may not be available any more but it allowed the use of either the O-320 B3C or the O-360 ??? taken from the Apache . The 175 flys like the 172 though as noted its a little heavier and larger than the 172 from the same year. The 1960 version went to the swept tail. It still has the handbrake style flap operation and 40 deg flaps which is really nice. Getting rid of the gearbox is a good thing.....>

Frank
 
Man, a 175 with a 470 (or a 390) sounds like a barrel of fun.
 
So would the replacement just eliminate the gearbox and be a "conventional" Cessna 17X?

Is the 175 a different airframe than a 172 or 177?
The Airframes are identical except for two additional stiffeners in the fuselage, different cowling and bigger gas tanks.
Fun Fact: All new generation "172's" are built on the 175 type certificate 3A17, not the 172 TC-3A12.
 
Man, a 175 with a 470 (or a 390) sounds like a barrel of fun.

Just curious, in what way are you thinking? A friend of mine flew an o-470 powered 175 quite a bit and both he and the owner disliked it. Apparently the STC didn't allow an increase in airspeed beyond the original limitations so he said the airspeed made the use of the extra power a bit limited. The owner ended up selling it to a drop zone, who loved it for their use.

If I were to get a 175 I'd be pursuing the same engine swap as Tom wants. It should be light and make good power, plus be supportable. A 220 Franklin might not be too bad either, although although less supportable than the Continental IO-360.

I'd love to put the Conti 360 on my Stinson, but it doesn't appear that the STC for it is supported anymore.
 
Fun Fact: All new generation "172's" are built on the 175 type certificate 3A17, not the 172 TC-3A12.
You sure? I just looked at 3A17 on the FAA site (revision 47, July 2015), and there's no mention of 172R or 172S (the re-start models built since 1996). It includes the 175 series, P172D (Skyhawk Powermatic, the renamed 1963 version of the 175), R172 series (Reims Rocket, T-41B/C/D, Hawk XP) and the 172RG Cutlass RG.

172R and 172S are included in 3A12. Section 2 of the POH says, "The Cessna Model No. 172S is certificated under FAA Type Certificate No. 3A12."
 
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The Airframes are identical except for two additional stiffeners in the fuselage, different cowling and bigger gas tanks.
Fun Fact: All new generation "172's" are built on the 175 type certificate 3A17, not the 172 TC-3A12.

Incorrect.

You sure? I just looked at 3A17 on the FAA site (revision 47, July 2015), and there's no mention of 172R or 172S (the re-start models built since 1996). It includes the 175 series, P172D (Skyhawk Powermatic, the renamed 1963 version of the 175), R172 series (Reims Rocket, T-41B/C/D, Hawk XP) and the 172RG Cutlass RG.

172R and 172S are included in 3A12. Section 2 of the POH says, "The Cessna Model No. 172S is certificated under FAA Type Certificate No. 3A12."

Correct.
 
Thanks for that,, I'm trying to rationalize up-grading a 175 that really is a nice aircraft and can be bought for less than 20k, but the engine has a bad gear box.
I have a GO-300 engine that threw a rod, but managed an uneventful forced landing on a runway. The gearbox in this engine may be in serviceable condition. Feel free to contact me if interested. I do have the engine logs as well.
 
I have a GO-300 engine that threw a rod, but managed an uneventful forced landing on a runway. The gearbox in this engine may be in serviceable condition. Feel free to contact me if interested. I do have the engine logs as well.
How much free play does the gear box have.??
can you feel more than 1/4" free travel from full up to full down? at the tip of the prop?
 
I know nothing of the GO-300, but I used to fly behind the Lycoming GO-435 and the GO-480's. They're great engines if you just follow a few simple rules. So the fear of geared engines is totally irrational, in my opinion. That said, there might be something with the Conti geared engines that I do not know about or that makes them less serviceable. But if not - why not just overhaul the gearbox you have and fly that?
 
I imagine gearbox parts are made of unobtainium.
It's worse than that. There weren't many made, they wear out quick because pilots would not operate them correctly. and the spares are way long gone.
 
You sure? I just looked at 3A17 on the FAA site (revision 47, July 2015), and there's no mention of 172R or 172S (the re-start models built since 1996). It includes the 175 series, P172D (Skyhawk Powermatic, the renamed 1963 version of the 175), R172 series (Reims Rocket, T-41B/C/D, Hawk XP) and the 172RG Cutlass RG.

172R and 172S are included in 3A12. Section 2 of the POH says, "The Cessna Model No. 172S is certificated under FAA Type Certificate No. 3A12."

Man, I'm going to have to dig and find the previous revisions of the TC, I'm wondering if it was incorrectly listed and later Fixed, I bought my 175 in 2000 and I remember reading that oddity...
 
Look into the Franklin 220hp upgrade. We have a 175 at the home drome with that STC and the thing is a beast! 1,100lbs useful and 135ktas with lower fuel burn than a comparable 182.
 
It's worse than that. There weren't many made, they wear out quick because pilots would not operate them correctly. and the spares are way long gone.

I stumbled across a 175, in which my wife and I might be interested in. I believe to have a reasonably good understanding of the general pros and cons of the engine, including the 1200 h TBO. I however struggle with finding any information about what it would mean if the engine or the gearbox would have to be overhauled.

Are you saying that the gearboxes are likely to wear out and if they do, there is no way to repair them, while it would be hard to find a good used one?
What about the engine? Are there any parts which are likely for fail but which are unobtainable?

In this case, upgrading the engine would be in order, but most likely cost prohibitive. Quite a shame, as the 175 seems to be a really nice plane... :(
 
They are nice aircraft with the 180 horse Lycoming. But... the cost of a Lycoming 0-360 is twice the price of a IO_360, as is the costs of the STC. and the IO-360 can be a 210 horse.
There is also a STC to install the 220 horse PZL Franklin.

I've flown a Franklin 220 HP C175. VERY nice. It's basically a 182. Useful is 1,100lbs and will true out at 130+ and she'll climb like a beast.
 
I know this is old, but I searched and this was the most recent discussion I could find.

I’ve found a straight tail 175 for a really good price. The GO-300 is at time and has not run in a year. The plane hasn’t had an annual for 5-6 years. I could have the GO rebuilt but saw glowing reviews of 175s repowered with the O/IO-360 with 180-200hp. I’ve tried to track down the STC holders but the only one who I contacted that has any interest is Stoots. Their kit is $15K plus motor.

I am hoping to find a more DIY solution, ie: paying for a parts list so that I could acquire used parts and keep the cost of conversion down. The Lycoming seems like a real improvement in terms of power, parts availability and resale.
 
$15k plus motor isn't out of line. The conversions for 172s run the same. You get the needed bits and the paperwork for it, and it'll be easier and cheaper compared to trying to do the conversation on your own.
 
Man, a 175 with a 470 (or a 390) sounds like a barrel of fun.

It is fun. Our glider club has one. Bob Park, former member of our club, did a couple with O-470's. I think Mark Wiebe now holds that STC. Forward CG is an issue with it, but it makes a good towplane! With the O-470 and Horton STOL kit it tows better than our prototype 182.
 
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