Basics on 4 Cycle Gas Engine
03-18-2018, 07:57 PM
#1
Thread Starter
Join Date: Dec 2016
Posts: 9
Likes: 0
Received 0 Likes
on
0 Posts
Basics on 4 Cycle Gas Engine
I'm a rookie in this hobby. Ran an OS Max 46 on my trainer last year and thinking about moving to a 4 stroke gas motor for my next kit build. Where can I go for all the basics of a gas motor, i.e. size as compared to nitro size, difficulty in mounting, starting, adjusting for optimum running, everything? I know nothing and need to learn from the very basics all the way up. Where can I go for that information? Thank you.
03-19-2018, 03:07 AM
#2
Hi,
You can use the search function of this site to find a lot on the subject as it has been discussed many times over.
Here are some 4-stroke gas engines that describe what applications they are suited for.
https://www.horizonhobby.com/storefr.../saito-engines
For a 40 size trainer or Cub-style plane the Saito FG-11 would be an engine to consider:
https://www.horizonhobby.com/product...%3A-bz-saieg11
Following the break-in process is very important as well as using high quality oil and gas. The adjustments and maintenance will be similar to a 4-stroke glow engine which is a bit more involved than 2-stroke glow or gas.
You can use the search function of this site to find a lot on the subject as it has been discussed many times over.
Here are some 4-stroke gas engines that describe what applications they are suited for.
https://www.horizonhobby.com/storefr.../saito-engines
For a 40 size trainer or Cub-style plane the Saito FG-11 would be an engine to consider:
https://www.horizonhobby.com/product...%3A-bz-saieg11
Following the break-in process is very important as well as using high quality oil and gas. The adjustments and maintenance will be similar to a 4-stroke glow engine which is a bit more involved than 2-stroke glow or gas.
03-19-2018, 07:52 AM
#4
First of all 4 stroke gasoline engine choices are not all that plentiful. 2 stroke gasoline engines have generally ruled the roost for many years because of the simplicity and available power to weight. That being said the four strokes have been making some very good inroads especially in the smaller displacements.
Most if not all four strokes you will find still have to use a gas/oil mix similar to a two stroke. In fact 16:1 or 20:1 which will distribute more oil deposits than a standard 2 stroke at 40 to as high as 100:1.
Any gasoline engine needs a fine and delicate hand adjusting carb settings. With gasoline the air fuel mixture has to be right on to work well at all throttle settings where nitro fueled engines have a much courser needle valve adjustment. Nitro has a much wider range air fuel wise that the engine will operate in.
Size of your chosen model will depict how many options you have for engine choice.
Not trying to talk you out of a gasoline four stroke by any means. Perhaps instead you might tell us your choice of model and size then some with experience might be able to suggest an appropriate power plant. Are there reasons why you are leaning towards a gasoline four stroke? There is lots of experience on the forum and lots of advice and help if you want or need it.
Dennis
Most if not all four strokes you will find still have to use a gas/oil mix similar to a two stroke. In fact 16:1 or 20:1 which will distribute more oil deposits than a standard 2 stroke at 40 to as high as 100:1.
Any gasoline engine needs a fine and delicate hand adjusting carb settings. With gasoline the air fuel mixture has to be right on to work well at all throttle settings where nitro fueled engines have a much courser needle valve adjustment. Nitro has a much wider range air fuel wise that the engine will operate in.
Size of your chosen model will depict how many options you have for engine choice.
Not trying to talk you out of a gasoline four stroke by any means. Perhaps instead you might tell us your choice of model and size then some with experience might be able to suggest an appropriate power plant. Are there reasons why you are leaning towards a gasoline four stroke? There is lots of experience on the forum and lots of advice and help if you want or need it.
Dennis
03-21-2018, 07:17 AM
#5
Thread Starter
Join Date: Dec 2016
Posts: 9
Likes: 0
Received 0 Likes
on
0 Posts
Thank you for the information and advice gentlemen. After reading your posts and some other research I've done, I've decided to stay with nitro engines until I get more experience and work with my club's members who fly the 4 strokes. I don't think I'm ready to move this fast with what little I know. I built a second plane this winter, a Sig Somethin Extra, and put an OS Max 46 on it. Hope to fly it later this summer. I just bought a Mustang P-51 kit and thought about the 4 stroke motor for it, but have changed my mind, goinggto try to find a good, used OS Max 61 to 91 for it. Thanks again you guys. This forum is a great place for good info and advice.
Jim
Jim
03-21-2018, 08:24 AM
#6
Thank you for the information and advice gentlemen. After reading your posts and some other research I've done, I've decided to stay with nitro engines until I get more experience and work with my club's members who fly the 4 strokes. I don't think I'm ready to move this fast with what little I know. I built a second plane this winter, a Sig Somethin Extra, and put an OS Max 46 on it. Hope to fly it later this summer. I just bought a Mustang P-51 kit and thought about the 4 stroke motor for it, but have changed my mind, goinggto try to find a good, used OS Max 61 to 91 for it. Thanks again you guys. This forum is a great place for good info and advice.
Jim
Jim
Something like this https://www.osengines.com/engines-ai...900/index.html
Here is the manual compare it to what you know about the two strokes and see if its within your comfort zone.
Last edited by Propworn; 03-21-2018 at 08:37 AM.
03-31-2018, 07:17 AM
#8
Moderator
Is the appeal of a gas 4 stroks just to do something different, or are you looking for something specific performance wise? The thing with gassers is that they both run near the same RPM. Is not like the difference with glow fuel where the 2 stroke runs 14k and the 4 stroke tops out at 10k with a lot more torque. All you really get with a gas 4 stroke is better fuel economy, which isn't really that big a deal with gas. I'm a fan of the new gas 2 strokes, as they run very similar to a glow 4 stroke with the simplicity of a 2 stroke and the cheap fuel.
04-01-2018, 05:42 AM
#12
Hey Jaka hows it going? I know nothing about your native language however English is an extremely dynamic form of communication and is constantly changing and it 'is what it "currently" is.
Now actually I agree with you and have always referred to the bulk of my fleet as 'glow planes with glow engines' and I will continue to use those terms till I croak However times have changed and perhaps the term nitro, referring to the type of engine we mostly used started to be used far more often by the folks into RC cars. I think this slow change started in the late eighty and early nineties.
So you see my friend it matters not whether you or I may 'grow tired of it' it is what it is, if we want to continue to communicate in English.
John
Now actually I agree with you and have always referred to the bulk of my fleet as 'glow planes with glow engines' and I will continue to use those terms till I croak However times have changed and perhaps the term nitro, referring to the type of engine we mostly used started to be used far more often by the folks into RC cars. I think this slow change started in the late eighty and early nineties.
So you see my friend it matters not whether you or I may 'grow tired of it' it is what it is, if we want to continue to communicate in English.
John
