New to gas. Advice anyone?

[Chuppster]

I've gotten comfortable with electrics but I have yet to delve in the world of gas/fuel.

There's a guy that is selling a few gas RC airplanes and they seem to be a decent price. They range from 50cc to 100cc gassers, and he said he has some Nitro models too. I plan to go check them out this weekend but I don't know much about model airplane engines. I've been wrenching on cars and lawn mowers for years but nothing like this.

What kind of things should I be looking fore before I pull the trigger on a model? How much to gas engines differ based on a given displacement? What are some red flags? Is there a guide somewhere on how I can start/test the engines and see how they run? The seller has 30 years in the hobby but I don't want to rely solely on his opinion.

Any advice for this newbe would be greatly appreciated!

 

[Bricks]

One thing to look for is if the spark is magneto versus electronic the magneto will run all right but adds a ton of weight and not worth much if anything any more, if possible go electronic, or adjust price way down. Basically like any engine how is the compression if compression is good and turning the motor over feels smooth with no roughness then I would not worry about the engine. Who is the manufacturer of the engine makes a big difference in value. Check for soft wood around the firewall if not sealed properly will weaken. Check if hinges are tight, and type of hinges one piece plastic is OK but they do fail after some use. Overall condition of the planes look clean and not a ton of repairs done to them, adjust price up or down. Type of servos standard or digital all these things can determine price up or down. Any plane you do purchase get as much information about it who made it kit or ARF, type of flight pack and voltage etc.

Good luck and ask questions

Edited to add If cheap enough then many things can be changed and still be a good deal.

 

[Chuppster]

One thing to look for is if the spark is magneto versus electronic the magneto will run all right but adds a ton of weight and not worth much if anything any more, if possible go electronic, or adjust price way down. Basically like any engine how is the compression if compression is good and turning the motor over feels smooth with no roughness then I would not worry about the engine. Who is the manufacturer of the engine makes a big difference in value. Check for soft wood around the firewall if not sealed properly will weaken. Check if hinges are tight, and type of hinges one piece plastic is OK but they do fail after some use. Overall condition of the planes look clean and not a ton of repairs done to them, adjust price up or down. Type of servos standard or digital all these things can determine price up or down. Any plane you do purchase get as much information about it who made it kit or ARF, type of flight pack and voltage etc.

Good luck and ask questions

Edited to add If cheap enough then many things can be changed and still be a good deal.

Thanks for the advice. I forgot to comment, I picked up some airplanes on Saturday. Feel free to check out what I found and offer any advice!

https://forum.flitetest.com/index.php?threads/diving-into-fuel.55366/#post-430177