C150 Engine Upgrade

If the O-200 doesn't make more power/thrust than the C-85, why is it popular to replace the C-85s on 140s with O-200s?
 
Touching on the skycatcher I recently found this video. I really enjoy this guys videos and he is very knowledgeable.


The channel is skywagon university and he does videos with local pattern flights on a lot of planes.
 
Pinecone said:
If the O-200 doesn't make more power/thrust than the C-85, why is it popular to replace the C-85s on 140s with O-200s?
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I don't think anyone suggest the O200 doesn't make more power than a C85 and from experience I know without a doubt it does. There are always rumors that a C90 makes more power than an O200 but I have never seen actual comparable evidence. I have seen dyno graphs and they all show the O200 making slightly more HP. The thrust test I've seen are comparing an O200 propped for a C150 vs a C90 propped for a 140A. The larger diameter prop on the 140A is going to make more static thrust. The proof I need to be a believer is the same diameter prop on both engines pitched to reach their static RPM rating. The C90 has a higher lift cam but is limited to 2475 rpm I believe. The O200 can run 2750 continuous.
 
Thinking with all the 150's out there, there isn't an STC for the Continental 0-240 that Reims did for the Areobat
 
hish747 said:
The Cessna 150's O-200 had at one time an AD that required retarding the mag timing. I bought such a 150 and realized that because it had actual Lycoming cylinders, the mag timing could be returned to the original. it definitely made a difference, especially in climb performance. It would be worthwhile to investigate the paperwork for the plane in question. You may be able to gain some "free" horsepower.
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So you actually bought a 152 with Lycoming cylinders and most likely 108 hp. The retarding AD on Continentals is unlikely to be applicable to many engine still in the fleet (though it is possible of course).

A 120 or 140 with a stroked C85 is a very good performer, but so is a light 150 with the O200.
 
Ventucky Red said:
Thinking with all the 150's out there, there isn't an STC for the Continental 0-240 that Reims did for the Areobat
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Brand new to the site…first post so “Howdy”! I had a 1972 A150L Aerobat growing up in the 1980’s and we looked into putting a 150hp conversion on it (which it desperately needed for Aerobatics)…problem was the conversion took the aerobatic certification away …
 
Cessna putting the continental in the skycatcher instead of a rotax has always seemed like a miss, especially considering the prototype has a rotax

But then again, there's a lot of things about the 162 that was a miss.
 
PilotAl said:
Brand new to the site…first post so “Howdy”! I had a 1972 A150L Aerobat growing up in the 1980’s and we looked into putting a 150hp conversion on it (which it desperately needed for Aerobatics)…problem was the conversion took the aerobatic certification away …
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Welcome aboard!
 
I think there is one 150hp STC that preserves the spin and aerobatic categories.
 
Like souping up a Volkswagen beetle. You can put a turbocharger on it, but it's still a bug.

Of course, I've flown one of these reengined 150s and it is a hoot (almost as much fun as a fast beetle).
 
Is there a cost to the shop to get an STC approved by FAA?
 
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My 150 needs an overhaul soon. Not sure what to do since the price to overhaul is so insane. Glorified lawn mower engine. Leaded fuel will be done for sooner than later. I would rather put a Rotax in it.
 
If you’re willing to share - what is the overhaul cost that you’re looking at?
 
Its impossible to get any remotely firm prices out of anyone locally. I assume cam and lifters are all junk at this point. New bearings. Cylinders are all fairly new. Bottom end hasn't been open since 1973 so..... 2200 SMOH. I still have great oil pressure and 10-13 hours before dumping in another quart. One OH shop said to run it until 2500 hours then overhaul.
 
For an O-200 it's 46K for a factory new and 44K for a factory overhauled engine.
 
I'd be happy if someone could come up with an STC to replace the O-200 with a Rotax as an engine change only and not a change to the aircraft (not enough of mine made to make it cost effective to get an STC for the aircraft). That's not going to happen, alas.
 
farmrjohn said:
I'd be happy if someone could come up with an STC to replace the O-200 with a Rotax as an engine change only and not a change to the aircraft (not enough of mine made to make it cost effective to get an STC for the aircraft). That's not going to happen, alas.
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makes sense to me. Rotax appears to be about 10k cheaper for the same or better turbo power.
 
farmrjohn said:
I'd be happy if someone could come up with an STC to replace the O-200 with a Rotax as an engine change only and not a change to the aircraft
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FWIW: I believe someone did get an STC in the EU and is stilling working on getting it approved in the US. But you also could go the Experimental/Exhibition route and put a Rotax on your aircraft with as minimal modifications as you want right now. Its one route a number of people have taken to install different engines without an STC. Why wait on someone else to do the work?
 
Bathman said:
For an O-200 it's 46K for a factory new and 44K for a factory overhauled engine.
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And essentially nobody with an aircraft in the value range of those fitted with an O-200 is going to select either of those options. They will instead have their existing engine overhauled or IRAN'd by an independent engine shop or A&P mechanic, at lower cost. Cessna 150s and the like are mostly hobby planes in 2023, with owners unwilling to splurge on unnecessary expenses. These are planes that independent owners fly for limited hours and keep running at minimum cost. Flight schools with money fly 172s and Pipers.

The Rotax 915 idea is a pipe dream. Putting a very expensive liquid cooled, geared, turbocharged, EFI engine with a constant speed prop on a very simple, basic, low value used aircraft with an expensive STC conversion kit is not something the market will choose, or has chosen. The French company that tried to market the idea using a simpler 912 Rotax (that like the 915 also requires a wood CS prop to work) failed to sell an appreciable number of conversions over the years they tried to do so. If I understand the website correctly they sold the EASA STC rights in 2017 to somebody in Finland.

rotax-cessna.com

ROTAX CESSNA

rotax-cessna.com rotax-cessna.com

A prototype was built and flown years ago, I believe a few sales followed but a year and half ago the website again said “A goal has been set to convert one C150 in 2022 to gain experience in the production to cover possible pitfalls and to get precise understanding of the actual cost of STC kit. After first conversion a full scale production capability should be achieved”
 
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Racerx said:
Cessna putting the continental in the skycatcher instead of a rotax has always seemed like a miss, especially considering the prototype has a rotax

But then again, there's a lot of things about the 162 that was a miss.
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Didn't they destroy the last remaining airframes?
 
Nope. There is one flying at my airport. As a rental and instruction airplane for people to do a Sport Pilot Certificate. FBO has purchased one or two crashed ones for parts.
 
Fast Lane said:
Its impossible to get any remotely firm prices out of anyone locally. I assume cam and lifters are all junk at this point. New bearings. Cylinders are all fairly new. Bottom end hasn't been open since 1973 so..... 2200 SMOH. I still have great oil pressure and 10-13 hours before dumping in another quart. One OH shop said to run it until 2500 hours then overhaul.
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I would make a spreadsheet and summarize the total time on components and the dates they were installed for magnetos, spark plugs, spark plug wires, exhausts, alternator, vacuum pump, cylinders, hoses, oil cooler, engine mount, and go from there. If some of those are pretty new then it makes zero sense to replace them.

Core engine overhaul, $1700 crankshaft, maybe $700 rods, $400 on rockers, $1200 crankcase, maybe $1k in bearings and bolts, new cam & lifters or reground ones is gonna be a personal choice.

The last O200 I overhauled was kind of a worn out pile. It needed a new accessory case as the oil pump cavity was worn out, the cam gear NDTed cracked, the magneto drive gears and bushings were shot and the crankshaft was unusable.

There is zero reason not to buy a set of new cylinders long before you overhaul. Just make sure they are preserved correctly or they may be rusted out trash when you finally use them. Inspect them as soon as they are delivered as I have gotten brand new cylinders with corroded barrels and rejected them the day they showed up. AND DO NOT LOSE THE PAPERWORK FOR THEM. You may end up just selling them at some point like if your airplane got totaled by tornado or something.
 
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Dave Arata said:
I've got a 150hp C-150. While the climb performance is nice, it makes any longer trips more complicated due to fuel considerations. I plan for roughly 2.5 hours between fuel stops. You won't see a dramatic increase in speed, either. Having said that, I recently flew a "standard" 150 with the O200 and I will NEVER fly one again! :)
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Dave, I've got a 150M with an o-320 in it. I'm trying to get ready for a check ride and looking for info on W&B. Do you happen to have any info on this?
 
MBishop48 said:
Dave, I've got a 150M with an o-320 in it. I'm trying to get ready for a check ride and looking for info on W&B. Do you happen to have any info on this?
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Huh? The weight and balance is specific to the aircraft. You need the data for your specific plane. And that’s not just for a check ride, but for every flight.
 
Salty said:
Huh? The weight and balance is specific to the aircraft. You need the data for your specific plane. And that’s not just for a check ride, but for every flight.
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Looking for the CG envelope change from standard
 
Salty said:
Huh? The weight and balance is specific to the aircraft. You need the data for your specific plane. And that’s not just for a check ride, but for every flight.
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From this, I suspect he's not ready for any checkride. The examiner will grill him on W&B, where to find the relevant info and how to calculate it for the exam flight. And if he isn't ready for that, what else is he not ready for?

His instructor(s) have been lax. That's not his fault, but he's not been getting what he's been paying for.
 
Jeebus why don't y'all find out the specifics of what he's looking for before you throw him under the bus?

Nauga,
and the rush to judgement
 
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nauga said:
Jeebus why don't y'all find out the specifics of what he's looking for before you throw him under the bus?

Nauga,
and the rush to judgement
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Yea, thanks. I appreciate someone taking a minute to not over analyze my training and knowledge. Due to the larger motor and the revised CG envelope I'm struggling a little with putting together the information. I have the weights and the CG, however the CG moment envelope is now different than when the plane was built. The original envelope in the POH was topped out at about 1600, after the STC it went up to about 1750 I believe. I'm trying to confirm this information. I was simply looking for the information or experience others in my situation may have used.

My plane is not your standard out of the box 150 where data is readily available.
 
MBishop48 said:
Yea, thanks. I appreciate someone taking a minute to not over analyze my training and knowledge. Due to the larger motor and the revised CG envelope I'm struggling a little with putting together the information. I have the weights and the CG, however the CG moment envelope is now different than when the plane was built. The original envelope in the POH was topped out at about 1600, after the STC it went up to about 1750 I believe. I'm trying to confirm this information. I was simply looking for the information or experience others in my situation may have used.

My plane is not your standard out of the box 150 where data is readily available.
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I’m sorry but I don’t understand where nauga is coming from. What you are saying is not how it works. You don’t make this crap up from asking people on the internet. An accurate weight and balance is calculated when a modification is made with actual data available at that time, or the plane is actually weighed. It is a document for your specific aircraft and is a required document for your aircraft to be airworthy. You don’t just plug a bunch of random swag numbers into the poh w&b and use it.

If you don’t have an accurate document then you have to weigh the plane. It’s as simple as that.

And it has to be signed by an A&P for it to be valid.
 
Love a nice math problem.

The datum point did not change, so despite the new aircraft weight and aircraft center of gravity the original pilot/co pilot, baggage, and fuel arms are unchanged.

And since the wing and fuselage didn’t change, your forward and aft CG limits haven’t changed.

Salty is right. You have to have an official weight and balance done and signed by an A&P and be logged. You have to affix this official document to your POH.

As far as weight and balance envelope, what has changed is your allowable take off weight. (maybe your landing weight as well? Probably not).

I can’t see how your forward and aft limits could have moved with the new engine.

Did you research the STC that allowed your engine modification?
 
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Dan Thomas said:
From this, I suspect he's not ready for any checkride. The examiner will grill him on W&B, where to find the relevant info and how to calculate it for the exam flight. And if he isn't ready for that, what else is he not ready for?

His instructor(s) have been lax. That's not his fault, but he's not been getting what he's been paying for.
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Salty said:
I’m sorry but I don’t understand where nauga is coming from. What you are saying is not how it works. You don’t make this crap up from asking people on the internet. An accurate weight and balance calculated or actual weighed, for your specific aircraft is a required document for your aircraft to be airworthy. You don’t just plug a bunch of random swag numbers into the poh w&b and use it.

If you don’t have an accurate document then you have to weigh the plane. It’s as simple as that.
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Salty, please excuse my obvious ignorance then and see if you can aid a fellow human who is in the process of learning.

After you've figured out your loaded aircraft weight do you not take that weight and verify that it falls within the center of gravity envelope that has been provided in the POH? Now imagine that envelope has changed and that the graph in your POH is no longer valid.

I'm not plugging random swag numbers in and I'm not making crap up. I have the weights.
 
WDD said:
Love a nice math problem.

The datum point did not change, so despite the new aircraft weight and aircraft center of gravity the original pilot/co pilot, baggage, and fuel arms are unchanged.

And since the wing and fuselage didn’t change, your forward and aft CG limits haven’t changed.

Salty is right. You have to have an official weight and balance done and signed by an A&P and be logged. You have to affix this official document to your POH.

As far as weight and balance envelope, what has changed is your allowable take off weight. (maybe your landing weight as well? Probably not).

I can’t see how your forward and aft limits could have moved with the new engine.

Did you research the STC that allowed your engine modification?
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THANK YOU WDD! I appreciate you taking the time to try to answer the question as opposed to the previous comments.

If the takeoff weight changed, the envelope would have changed as well, correct?
 
Good luck!
 
Salty said:
If you don’t have an accurate document then you have to weigh the plane. It’s as simple as that.

And it has to be signed by an A&P for it to be valid.
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If you have an accurate weight and balance but weren't provided the correct envelope or limitations then it's not as simple as you state.

MBishop48 said:
If the takeoff weight changed, the envelope would have changed as well, correct?
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If the new allowable takeoff weight exceeded the max weight on the original envelope then the envelope would change, if it were to be 'legal'
There should be a new envelope or limitations as a result of the STC or whatever vehicle you used for the weight increase.

Your question seems reasonable to me...maybe I'm not ready for a checkride either.

Nauga,
flying off the runway, not the handle
 
nauga said:
If you have an accurate weight and balance but weren't provided the correct envelope or limitations then it's not as simple as you state.
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and the solution is to ask the internet?
 
nauga said:
If the new allowable takeoff weight exceeded the max weight on the original envelope then the envelope would change, if it were to be 'legal'
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Again, I would research the STC for the new engine. That surely must include a new higher weight W&B envelope for you showing a higher take off weight. It won’t be greater forward or aft, but taller allowing more gross weight.

Ask the STC creator. Maybe also contact the A&P who did the work for direction in where to get that documentation.

That official W&B documentation combined with your recent official unfueled and empty weight and balance by your A&P, conbined with the ARMs in the POH for fuel, pilot/copilot, and baggage will be what you need to do your W&B calculations before flight.
 
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WDD said:
The datum point did not change...
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If only that were always true...it would have saved me a lot of time chasing down a 10" CG discrepancy between two almost identical airplanes.

Nauga,
shifted
 
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