Engine options...

Ask Questions and Offer Advice Related to the Cessna 120 & 140 Type
Forum rules
You must be a member of the Cessna 120-140 Association in order to post new topics, reply to existing topics, or search for information on this forum. Use the "Join" link in the red menu bar.
8404
Posts: 5
Joined: Fri Feb 15, 2019 11:00 pm
Name: Ian S
Aircraft Type:
Occupation-Interests:
Contact:

Engine options...

Post by 8404 »

Hi Everyone

Im sure this has been brought up many times...I have a project 48 140 in barn that I am beginning to put back..It has a C90-12 but I am interested in a more powerful engine. I know of the C-85/90 with an O200 crank...and O200,O235,O290....Would be very interested to hear from you all on this...is there a concensus? I knew a fellow near me years ago who put 150hp in his 140 A ..an O320? Bill Copp...now gone ...he said it worked very well..Likely over kill in a 140 though...heavy as well..

Cheers

Ian
8359
Posts: 229
Joined: Tue Nov 27, 2018 10:53 pm
Name: Tamer A
Location: KSNA
Aircraft Type: 1946 C120 O-290-D
Occupation-Interests: Engineer
Contact:

Re: Engine options...

Post by 8359 »

I like my O-290-D, but it definitely has it's drawbacks. Finding parts can be tricky, and the collection of STCs for the C120/140 often don't apply to it. It weighs a little more, mine has a few lbs in the tail to help balance it out and you lose a bit of useful load. But I do see about 130-140MPH cruise often and the thing takes off like a bat out of hell, even at full gross.

I think if I were starting with a blank canvas I'd look closely at the O-235 and try to find ways to lighten it up. Parts aren't an issue like they are with the O-290 and the 235 is on the TCDS.

Take all this with a grain of salt, I'm a new 120 owner and have limited experience.
Image
User avatar
6643
Posts: 2444
Joined: Tue May 01, 2018 7:00 am
Name: John C
Location: KLCI, NH
Aircraft Type: 1946 C140/C90
Occupation-Interests: A&P, semi-retired
Contact:

Re: Engine options...

Post by 6643 »

The C90 has the same crank as the O200, or, if you go chronologically, the O200 has a C90 crank...

I like my C90. The problem I see with all the other options is weight. There was a plane at one of the conventions many years ago, that had (IIRC) an O360 (may have been an O320) in it. We had a weighing clinic, and after weighing his plane, he started looking for a ride home for his wife.
8404
Posts: 5
Joined: Fri Feb 15, 2019 11:00 pm
Name: Ian S
Aircraft Type:
Occupation-Interests:
Contact:

Re: Engine options...

Post by 8404 »

Thank you both for input...I did not realize that my C90 has an O200 crank...interesting...My Dad had a Pacer with the O290D2 ...he loved it! The O235 does look like a good contender...there is a version F,G,and J with 125HP...Im coming off 13 years owning a Maule MX7-235...lol...Im not trying to duplicate that kind of performance but certainly a few more horses would be fun in the 140...I will have a look at the STC for the O235s...
8404
Posts: 5
Joined: Fri Feb 15, 2019 11:00 pm
Name: Ian S
Aircraft Type:
Occupation-Interests:
Contact:

Re: Engine options...

Post by 8404 »

How is the fit of the O290D? What are the parts issues on the O290s....Ive heard this too, but wondering what parts are difficult to find...
8359
Posts: 229
Joined: Tue Nov 27, 2018 10:53 pm
Name: Tamer A
Location: KSNA
Aircraft Type: 1946 C120 O-290-D
Occupation-Interests: Engineer
Contact:

Re: Engine options...

Post by 8359 »

Thankfully (knock on wood) I haven't had to get any parts yet, but then again I'm a new owner. From what I've heard finding cylinders can be a little tricky and you can expect to pay about double.

Pretty much everyone who has looked under my cowl is amazed it's stuffed under there. They all say it looks pretty tight. I haven't seen a standard 120 in person yet though to compare.
Image
5557
Posts: 13
Joined: Tue May 01, 2018 7:00 am
Name: Tom Macdonald
Location: Laveen, AZ (AZ90)
Aircraft Type: 46 Cessna 120
Occupation-Interests: A&P IA Mechanic
Contact:

Re: Engine options...

Post by 5557 »

I recently completed a complete field overhaul on my O-235-C1C. It had 2500 hours TSN, and about 25 years since it had been installed on my '46 120 under STC SA 95. We in the 120/140 Assn got lucky when Gus Warren, a member, acquired the STC and began offering complete data packages; before that, for a long time, the original STC owner(s) had been very unresponsive. I have mixed feelings about the installation. While I was able to easily find all parts I needed for overhaul and continued support, and the engine offers me good performance, particularly here in AZ in warmer weather, higher terrain and increased density altitude, there is a weight penalty. My original factory empty weight with the C-85 was somewhere around 850 lbs. With the O-235 , alternator, lightweight starter, battery, vacuum pump, and average avionics and interior, my current E.W. is 1040 lbs. The resulting useful load of 410 lbs means that with full fuel (150 lbs) and a bigger boy like me (230 lbs), I can't fly with a passenger or other load of more than 30 lbs. If you really have a choice, I would seriously consider Randy Thompson's O-200 STC, because the tradeoff of being lighter, and having 100 BHP for increased performance is probably an optimum combination for performance and utility. And the form/fit/function of the Continental is undoubtedly less problematic. My O-235 required all sorts of cowling mods. If people want significantly bigger engined airplanes, they would be better off flying 170's or 180's to get the full performance benefit, payload and performance, not payload or performance. I'm just sayin'. Good luck in your hunt.
8404
Posts: 5
Joined: Fri Feb 15, 2019 11:00 pm
Name: Ian S
Aircraft Type:
Occupation-Interests:
Contact:

Re: Engine options...

Post by 8404 »

Thank you Tom for the information....all useful...the O200 argument is a strong one...I will keep you all posted on the progress of my project...early stages so far..
Cheers
8359
Posts: 229
Joined: Tue Nov 27, 2018 10:53 pm
Name: Tamer A
Location: KSNA
Aircraft Type: 1946 C120 O-290-D
Occupation-Interests: Engineer
Contact:

Re: Engine options...

Post by 8359 »

95% of the people on here will tell you to get the O-200. It's the best bang of the buck and leaves you more useful weight. You'll also have the best support and knowledge base to pull from.
Image
User avatar
6643
Posts: 2444
Joined: Tue May 01, 2018 7:00 am
Name: John C
Location: KLCI, NH
Aircraft Type: 1946 C140/C90
Occupation-Interests: A&P, semi-retired
Contact:

Re: Engine options...

Post by 6643 »

Still awaiting the run-off between Randy's O-200 and my C90... ;)
Post Reply