Is a 172G still a good buy for my purposes?

Nico_490

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Nico_490
I’ve the option to buy a fifth in a 1965 Reims 172G in my Club. Since I just got my PPL and this would be my fist plane, I have a few questions and maybe you could help me out:

- It has the original O-300. So, the old 6 banger. Is this more a bug or a feature? I kinda like the smoothness but it has now ~1.800 Hours. The plane was always private and looked after. How reliable is such an engine still today? (In general. Will talk to our A&P next week)

- It's not really getting to 100kt. More around 90kt. Is this normal for this engine/plane-combination?

- It has an old panel but updated with a G5, new radios and a mode-S transponder. So quite alright for VFR-Flying. The only thing I found odd is the old mixture-lever, but should be alright, too i guess. For navigation and stuff, I'll use my phone + iPad.

- I love the 40-degree-flaps!

The plane would be quite cheap and so are the cost per hour substantial cheaper, than our more modern club cessnas. Plus more available.

So, I guess my main question about all this would be: Given it's age, could a plane like this be still a good VFR traveler for 2-3 people for weekend trips and building hours? Would you still fly an engine like this for short trips over water?
 
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Yes. I like the O-300s better than the later O-320 models. Non-pilot people are gonna turn their nose up equally at this thing as a cirrus or king air.

1800 is the TBO if I recall correctly, so your "share" may be a share in a $40,000 work order. :D

90kt is slow. I'd expect 105ish. The prop+motor may be tired, but 15kts is a lot to lose on one of these. It may need rigging help too.
 
A few thoughts.

How well funded is the plane’s mx reserves? If the motor came from together tomorrow, would a special assessment be needed and, if so, can you swing that?

If you’re flying goal includes an instrument rating, is the plane equipped to achieve that goal? If you want the IRA and the plane isn’t equipped, I’d pass.
 
Buying an airplane with an O-300 really depends on the application that you’re going to be using it for. They don’t hold up as well in the flight training environment as well as the Lycomings do. It likes constant high-power, with less throttle manipulation. If you’re going to be using the airplane to build time and generally for cross-country flying, the O-300 is a fine engine. That said, it’s becoming a bit harder to source parts for, so keep that in mind.

90kts seems slow. I’d agree with the 105kt comment above. Be sure to give it a methodical pre-purchase inspection, no matter how ‘cheap’ the asking price is.
 
Yes. I like the O-300s better than the later O-320 models. Non-pilot people are gonna turn their nose up equally at this thing as a cirrus or king air.

1800 is the TBO if I recall correctly, so your "share" may be a share in a $40,000 work order. :D

90kt is slow. I'd expect 105ish. The prop+motor may be tired, but 15kts is a lot to lose on one of these. It may need rigging help too.

Yea, it sounds way better, too. :)

Yes it‘s the TBO. And that‘s my biggest fear. Are there good statistics on how much longer they could run? I planning to ask our local A&P for the last compressions and a general evaluation. Is there anything else I could check as a noob?

OK. Maybe i‘ll check the speed again on another flight. Was not really on my mind.


@TCABM:
I think there is not much $, so there would be a special assessment. AND DOWNTIME! :eek:

Now i‘m working on my Night-VFR-rating. But a IFR-ticket is on my mind, too. But i‘m planning first to enjoy the VFR flying a few years. Till now flying is just for fun.

Buying an airplane with an O-300 really depends on the application that you’re going to be using it for. They don’t hold up as well in the flight training environment as well as the Lycomings do. It likes constant high-power, with less throttle manipulation. If you’re going to be using the airplane to build time and generally for cross-country flying, the O-300 is a fine engine. That said, it’s becoming a bit harder to source parts for, so keep that in mind.

90kts seems slow. I’d agree with the 105kt comment above. Be sure to give it a methodical pre-purchase inspection, no matter how ‘cheap’ the asking price is.

Yes, the bird would be used primarily for cross country and time building. All other pilots are quite experienced. Some retired corporate pilots.

Thanks for the help, guys!
 
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Yea, it sounds way better, too. :)

Yes it‘s the TBO. And that‘s my biggest fear. Are there good statistics on how much longer they could run? I planning to ask our local A&P for the last compressions and a general evaluation. Is there anything else I could check as a noob?

OK. Maybe i‘ll check the speed again on another flight. Was not really on my mind.


@TCABM:
I think there is not much $, so there would be a special assessment. AND DOWNTIME! :eek:

Now i‘m working on my Night-VFR-rating. But a IFR-ticket is on my mind, too. But i‘m planning first to enjoy the VFR flying a few years. Till now flying is just for fun.



Yes, the bird would be used primarily for cross country and time build. All other pilots are quite experienced. Some retired corporate pilots.

Thanks for the help, guys!

Night VFR rating? What country are you from?
 

@TCABM:
I think there is not much $, so there would be a special assessment. AND DOWNTIME! :eek:
Downtime is free and there really isn’t any data on how long past TBO a motor will go. I rented a US based 172 w/an O-320 that went 2980hrs between overhauls and the only reason the owner OH’d was insurance driven.

I would likely pass on this opportunity without a real good idea of the financials.

Our partnership has 1720hrs on an O-320 and enough cash on hand to buy a factory new motor and have it installed with all new firewall forward and accessories; when a share sells, those reserves are accounted for in the overall value of a share.
 
To offer anecdata contrary to what Ryan offered (and pointing out my anecdata is no more valuable than his :D ), we had an O-300 go way over 2x TBO to 4400 hours before it started making metal. Once it did, we flew it 25 hours to a place with an exchange engine for us on the shelf. They're big dumb lumps and we had a fondness for them.

Ours did 70 hour months pretty consistently, which was "average" for our fleet. The O-320/O-360 Skyhawks did fine also, and we ran an IO-360L2a to 4000 hours -- in a plane that was more likely to pull 90-100 hour months. The O-300 still had the longest TBO multiple in flight school service.
 
Downtime is free and there really isn’t any data on how long past TBO a motor will go. I rented a US based 172 w/an O-320 that went 2980hrs between overhauls and the only reason the owner OH’d was insurance driven.

I would likely pass on this opportunity without a real good idea of the financials.

Our partnership has 1720hrs on an O-320 and enough cash on hand to buy a factory new motor and have it installed with all new firewall forward and accessories; when a share sells, those reserves are accounted for in the overall value of a share.

OK, thanks for your opinion. It's not really a steal for its appearance and age, so i'm leaning to pass on this one, too. I really want to travel this year without to much of a headache.

@schookeeg: Thanks for the numbers! 4400 hours...wow. o_O
 
A few thoughts.

How well funded is the plane’s mx reserves? If the motor came from together tomorrow, would a special assessment be needed and, if so, can you swing that?

If you’re flying goal includes an instrument rating, is the plane equipped to achieve that goal? If you want the IRA and the plane isn’t equipped, I’d pass.

I'm sure a strut mounted machine gun and a few car bombs will get it IRA equipped.
 
My F-model indicated ~105 kts. at cruise power, about 118 kts. full chat, down low. Very smooth engine, however!
 
It depends on the cost of the buy in.my first airplane was a 1962 172. Flew it back and forth from ma.to Fla. That airplane is still flying with no problems. The airplane had a wing leveler when I purchased it,got my IFR rating with it.
 
- It's not really getting to 100kt. More around 90kt. Is this normal for this engine/plane-combination?
Well, let's look at the POH numbers for the 172H:

upload_2023-1-5_10-39-34.png

From http://www.aeroelectric.com/Reference_Docs/Cessna/cessna-poh/Cessna_172-C172H-1967-OM-bookmarked.pdf

So the first question you have to ask yourself: At what RPM is it being cruised? A lot of pilots seem afraid to run that RPM up in accordance with the POH, and that's silly. I've seen people cruising at 2400 and wondering why the thing doesn't go.

Second question: Has the pitot-static system been calibrated and checked for leaks? The tiniest pitot system leak will make the ASI underread a lot.

Third question: Has the tach been checked for accuracy?

Fourth question: Is the airplane out of ring? Are the flaps retracting all the way? Are the ailerons lined up with the fully-retracted flaps in flight?

Fifth question: Has a full-power static runup been carried out to see if that engine and prop are meeting the TCDS numbers?

From the TCDS:

upload_2023-1-5_10-47-47.png

You likely have the 1C172EM 7652 or 7653. If the static RPM is under 2230, either it has the wrong prop or the engine is tired. If it's over 2420, the prop is worn or dressed under limits. If it's within the range, the only excuse for the airplane to fly slowly is a worn-out prop on a worn-out engine. Much more likely it's one of the other problems I mentioned.
 
For me, I'd plan on immediately replacing the 50+ year, runout engine with a factory new engine. Probably $35-40K for that. I wouldn't even consider doing a major overhaul on an engine that old. I know plenty of people will disagree, but that's my opinion.
 
For me, I'd plan on immediately replacing the 50+ year, runout engine with a factory new engine. Probably $35-40K for that. I wouldn't even consider doing a major overhaul on an engine that old. I know plenty of people will disagree, but that's my opinion.

Kind of hard to do, since they are not making any O-300s any more.
 
For me, I'd plan on immediately replacing the 50+ year, runout engine with a factory new engine. Probably $35-40K for that. I wouldn't even consider doing a major overhaul on an engine that old. I know plenty of people will disagree, but that's my opinion.
Before I did that I'd go through the whole airframe and make sure there are no show-stoppers anywhere. Those old airplanes have plenty of weaknesses that can bite you in the wallet. The landing gear legs are famous for corrosion and pitting on their undersides, especially hidden under the entry steps, and those pits lead to catastrophic leg failure that would easily write the airplane off. The old wheels corrode between the halves and elsewhere, weakening them. The horizontal stab's forward spar cracks when people push down on it to turn the airplane on the ground. Control cables wear and corrode, pulley bearings dry out and seize the pulley, the trim jackscrew rusts and pits, the flap roller shells migrate and cut the flap support arms, the wing strut bulkhead in the cabin floor corrodes, the forward wing spar can suffer corrosion just outboard of the strut attach, between the spar joiner plates. The aft doorpost cracks right at its bottom where it joins the bulkhead. Lots of places that need checking in an old airplane. I'd also make sure there were no outstanding ADs, and that takes many hours to do.

I'd pull a cylinder off the engine and get a look at the cam and lifters and see if the cylinder is pitted. If it's all clean, and there was no metal showing in the screen or filter, and the compressions were good, I'd keep flying it. I'd take the mags off and do the internal inspection and cleaning and replace the points and condenser. I'd do the brush/commutator/slip ring inspection on the generator or alternator. If it has a dry vacuum pump I'd either inspect the vane wear, or if it's not a pump with the inspection provision, I'd replace it. I'd do a propeller corrosion and blade width/thickness inspections. All these items are things that would go onto the overhauled engine anyway.
 
Before I did that I'd go through the whole airframe and make sure there are no show-stoppers anywhere. Those old airplanes have plenty of weaknesses that can bite you in the wallet. The landing gear legs are famous for corrosion and pitting on their undersides, especially hidden under the entry steps, and those pits lead to catastrophic leg failure that would easily write the airplane off. The old wheels corrode between the halves and elsewhere, weakening them. The horizontal stab's forward spar cracks when people push down on it to turn the airplane on the ground. Control cables wear and corrode, pulley bearings dry out and seize the pulley, the trim jackscrew rusts and pits, the flap roller shells migrate and cut the flap support arms, the wing strut bulkhead in the cabin floor corrodes, the forward wing spar can suffer corrosion just outboard of the strut attach, between the spar joiner plates. The aft doorpost cracks right at its bottom where it joins the bulkhead. Lots of places that need checking in an old airplane. I'd also make sure there were no outstanding ADs, and that takes many hours to do.

I'd pull a cylinder off the engine and get a look at the cam and lifters and see if the cylinder is pitted. If it's all clean, and there was no metal showing in the screen or filter, and the compressions were good, I'd keep flying it. I'd take the mags off and do the internal inspection and cleaning and replace the points and condenser. I'd do the brush/commutator/slip ring inspection on the generator or alternator. If it has a dry vacuum pump I'd either inspect the vane wear, or if it's not a pump with the inspection provision, I'd replace it. I'd do a propeller corrosion and blade width/thickness inspections. All these items are things that would go onto the overhauled engine anyway.

Very good advise. Old planes are old planes. We tend to ignore that fact because sometimes old planes are all we can afford. Caveat emptor.
 
I'd pull a cylinder off the engine and get a look at the cam and lifters and see if the cylinder is pitted. If it's all clean, and there was no metal showing in the screen or filter, and the compressions were good, I'd keep flying it.

Not sure about the O-300, but on the -360 and larger Continentals, you can pull the lifters without pulling a cylinder or cracking the case.
 
Not sure about the O-300, but on the -360 and larger Continentals, you can pull the lifters without pulling a cylinder or cracking the case.
Can't. See the shape of the lifters? Mushroom head, meaning that the case has to come apart, which is why I suggested taking a cylinder off and having a look inside at least one bay.

upload_2023-1-5_19-6-15.png

One can't even get the guts out of the lifter without removing a cylinder. Those cylinders have permanently-attached pushrod tubes that fit into a housing around the lifters.
 
@Dan Thomas:
Thank you, that’s a great help for the next flight. I was a little in a honeymoon mode and would never look all this stuff up.
As far as I know, the reims build cessnas should handle corrosion a little bit better than the US made in general, because of the coating?! But for example, the step on the left main gear was missing and there was definitely some corrosion.

So after all, I’m thinking that I was too much fixed on the entry price (like always) and was wearing my rosy glasses, because I'm really like the idea of partial ownership vs. renting in the club. But if it’s hard to get an O-300 in the USA, then I'm guessing, it's even harder over here in Germany.

But at this stage I don't feel comfortable to buy a 50+ year old bird, without having all the knowledge that I should have for that. Despite that, I will talk to our local A&P about this plane and will let you know, what they will tell me.

Thank you guys, for the detailed comments. I really appreciate your help!
 
Crankshafts for a O-300 are scarcer than hens teeth and cost twice as much (currently $6500-9500 for a serviceable part).

The magnesium oil sumps typically have corrosion in the bottom. The approved epoxy lining doesn’t last, but the newly approved spray-weld method should. Normal welding creates heat and more cracks. Spray welding uses some form of high velocity, low heat application of metal. Mine cost $1,500.

Expect to pay up to $45,000 here in the USofA. I know nothing about costs on your side of the pond, but I imagine 30% higher.

I love my O-300. Starts easy, runs smoothly. Matched nicely to my 170.

40D4D3CA-2948-4DCF-BA20-046E7D67CB2C.jpeg
 
Here are some (bad) pictures, FWIW.
 

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Can't. See the shape of the lifters? Mushroom head, meaning that the case has to come apart, which is why I suggested taking a cylinder off and having a look inside at least one bay.

View attachment 113736

One can't even get the guts out of the lifter without removing a cylinder. Those cylinders have permanently-attached pushrod tubes that fit into a housing around the lifters.

Thanks.
 
I was a member of a LONG established club - time and corporate memory had coalesced the thinking into having enough $$$$ on-hand to replace/overhaul a 2000 hr TBO engine NLT 1500 hrs or so, just in case. I think that came from having to borrow from wealthier members a couple times over the decades. Then of course, the engines started routinely going well past TBO.

Get a look at the logs - that's an old bird IF it hasn't been well maintained - look for deferred maintenance (open squawks) on relatively low ticket items that have been put off for a while. If they've been going "cheap" look elsewhere. Ask if they've been using an oil analysis program - they're pretty cheap and it's not a big deal to send a sample at oil changes. When did that engine get installed/overhauled? It may be past calendar TBO - if the airplanes has had long periods of not flying the corrosion gremlins may be working their nasty.

Plenty of old airplanes, much older than 1965, are out and about. . .
 
if the airplanes has had long periods of not flying the corrosion gremlins may be working their nasty.
Sitting does little to it unless the atmosphere is really wet. It's ground-running it without flying it that rusts it out. Aircooled engines without PCV systems really hate that.
 
Hey, what is going on here? Is it still actual?
 
Hey guys, sorry for the late update.

With the typical seasonal bad weather over here, we had still no opportunity for a real testflight. So the most important thing is still to come.
But I had quite a long chat with our local A&P-shop about the plane and especially about the money-to-noise-generator.

- the compressions are all in the 70s.
- the shop tries to always have min. one O-300 in spare, because we’ve got some more O-300s running in our club.
- he kind of convinced me, that the plane is well looked after.
- It will be 1/4 instead of 1/5 of the plane. (Same buy-in price)
- I like the Mogas STC (before that, I was more skeptical about running it on different gas then what it was designed to.)
- He praised the actual owner, who is a retired CPL-pilot and A&P-mechanic. He does a lot of stuff by himself and the A&P signs it off after a check. This will keep the cost low, for low-ticket-stuff.
- I have a good feeling about the other owners.

So, with my other option is to charter this summer, I tend to buy the stake. Because I’ll be a lot more flexible and the variable cost will be more reasonable. And…OK…I kind of like the idea to have a share in a plane and just hop in most of the time. A club is a club, with the good, the bad and the ugly club-stuff.
So I hope that next week, we’ll get that thing into the air and I will check how it flies, stalls and how fast it really goes. And if I buy in and it will be a lemon. I don’t have to live under the bridge.
I’ll keep you updated. And still will be open for your helpful comments. Thanks a lot.

PS: excuse my bad English.
 
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A fifth share in a 172 is better than single ownership of anything. Parts range from hard to find to unobtainium for that engine, but still a good deal.
 
A fifth share in a 172 is better than single ownership of anything. Parts range from hard to find to unobtainium for that engine, but still a good deal.

Now it'll be 1/4 with one owner who has lost his medical, but still wants to own it. ;)
 
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