Diving into Fuel

[Chuppster]

I've wanted to try some fuel-powered airplanes (because I love engines... and noise!) for awhile now, and I saw an opportunity when a gentlemen posted an add stating he was trying to sell 200+ old airplanes he got from an estate. So, I jumped in my car and drove 3 hours to Ohio and here's what I came home with.

The one that will take the least work is a Weeks Solution biplane. I think it looks sweet, and it has an OS FS120 in it. Great compression, no issues with the bearings. I hope to try and start it today sometime. I am optimistic that it'll take at most a cleaning of the carb.

The gas model is an Extra 300. It didn't have any servos with it but the guy I bought it from just gave me five to use in it. The covering just has a few rips in it. I'm excited to fly it but it'll probably be the last one I try and fly out of the three. The engine is marked FPE 2.4 and it has good compression. It needs a muffler but that looks like about it.

Then I got this low-wing sporty-looking airplane with a Saito 150S. The engine is missing rocker covers and a needle, and it is stuck (I can't get it to turn). I've heard you can just bake it for awhile and it'll smooth out, any advice on this? I hope to find these parts for a decent price somewhere but not until I can get it cleaned up. This airframe looks like a lot of fun to fly, but the covering needs work.

The final price (with some tools thrown in the pile): $400. I think I did alright. Perhaps not the best deal ever made but everything is solid and straight, with good servos included.

I hope to document my journey with fuel here. Feel free to follow along, and if you have any advice I could use it! Thank you for reading!

 

[Bricks]

I have found if I use Marvel Mystery oil and dump some down the carb pull the plug dump some more oil, and let it sit and slowly keep working it it does a great job loosening up stuck engines unless the engine is blown.

Edited to add have the engine sitting upright.

 

[Chuppster]

I have found if I use Marvel Mystery oil and dump some down the carb pull the plug dump some more oil, and let it sit and slowly keep working it it does a great job loosening up stuck engines unless the engine is blown.

Edited to add have the engine sitting upright.

I just got done baking it and it's nice and free! I'll take some WD-40 to it and we shall see how it fares.

Before I put the back cover for the crankcase on, should I put some oil in it to lubricate it?

 

[Joker 53150]

Besides lubricating it make sure to clean it as well as possible - it looks like there is some debris on the rockers which you don't want getting into the oil passages.

 

[Chuppster]

Besides lubricating it make sure to clean it as well as possible - it looks like there is some debris on the rockers which you don't want getting into the oil passages.

Definitely!

I've been focusing on the OS 120 today. I got it to start, so that's good! I had to bypass the fuel pump however. It starts and runs for a minute but I believe there are some fuel delivery issues going on. Anyone have any experience with this? The fuel comes out just fine when I drain the tank, but I see bubbles when I draw it out with the engine. I may need to take out the fuel tank and re-plumb everything. Here's what the fuel pump looks like.

There's a little green ball that's not shown in the pictures. It goes between the spring and that large hole in the cover.

Any suggestions on what to try next would be helpful!

In other news, I cleaned up the other two airplanes and got some "Before" photos. They all need some body work.

 

[PsyBorg]

Air bubbles between the tank and the carb is usually either a bad seal on the tank, the "clunk" is above the fuel level, or there is a bad fit of the fuel line at the tank.

Fuel line is cheap so I suggest getting a few feet of it and replacing all the lines on each of these and save youself the anguish down the road.

Anyway I think you did well for what you paid. Thst edge alone new was more then what you got all that for.

Oh and make sure if these happen to be two stroke motors that they are always blowing a little smoke at all points of the throttle as thats how pistons are lubbed.

Otherwise you will seize the motor with a quickness.

 

[Chuppster]

Air bubbles between the tank and the carb is usually either a bad seal on the tank, the "clunk" is above the fuel level, or there is a bad fit of the fuel line at the tank.

Fuel line is cheap so I suggest getting a few feet of it and replacing all the lines on each of these and save youself the anguish down the road.

Anyway I think you did well for what you paid. Thst edge alone new was more then what you got all that for.

Oh and make sure if these happen to be two stroke motors that they are always blowing a little smoke at all points of the throttle as thats how pistons are lubbed.

Otherwise you will seize the motor with a quickness.

Alright, next step is to re-plumb the OS!

Does anyone know anything about electric ignition on a gasser? There's a canister going from the box to the plug (i'm guessing a coil?) and there's a second box that plugs into the first one. I don't see a way to get power into the system. I could use some help figuring out where the power should be applied.

Questions:

What are the two boxes? I'm assuming one is the ignition control but what is the other?
How do I get power to the ignition?

I may just take it apart, but I'd prefer to avoid that as it is so well wrapped up.

 

[Bricks]

Unhooking the fuel pump the engine will not run since there is no muffler pressure to feed fuel on your setup and most gassers run a fuel pump.

I myself have not seen an ignition setup like this before normally it is one box controls everything.

Might try here https://www.rcgroups.com/engines-140/

 

[Chuppster]

Unhooking the fuel pump the engine will not run since there is no muffler pressure to feed fuel on your setup and most gassers run a fuel pump.

I myself have not seen an ignition setup like this before normally it is one box controls everything.

Might try here https://www.rcgroups.com/engines-140/

It occurred to me today that the thing wrapped in foam inside the fuselage is probably the battery. They have a separate battery that they used just for the ignition. It's wired to the on/off switch on the side, and there is a charge port next to it. I hope the battery still functions.

 

[Joker 53150]

Most likely that IS a battery. Verify what voltage it is before replacing it (cheap insurance unless it's very new). Some systems require 5V and some 6V, and they can be somewhat delicate and easy to fry. Depending on the plane I've got both 5V and 6V batteries in use, all NiMh packs except for the biggest planes which use either LiPo or LiFe batteries.

With a gas engine you should strongly consider a fail-safe way to kill the engine. The electronic ignition you have is easily killed by using an optical-kill switch between the battery and ignition module. It's controlled by a spare channel on your receiver and isolates your ignition circuit from the receiver circuit - each circuit has it's own battery. A nice feature of this is that your ignition won't drain your receiver battery. If you had an older style ignition you could add a switch tripped by a servo to ground the coil to kill the engine. I've got both setups, but only one coil engine.

 

[Chuppster]

Most likely that IS a battery. Verify what voltage it is before replacing it (cheap insurance unless it's very new). Some systems require 5V and some 6V, and they can be somewhat delicate and easy to fry. Depending on the plane I've got both 5V and 6V batteries in use, all NiMh packs except for the biggest planes which use either LiPo or LiFe batteries.

With a gas engine you should strongly consider a fail-safe way to kill the engine. The electronic ignition you have is easily killed by using an optical-kill switch between the battery and ignition module. It's controlled by a spare channel on your receiver and isolates your ignition circuit from the receiver circuit - each circuit has it's own battery. A nice feature of this is that your ignition won't drain your receiver battery. If you had an older style ignition you could add a switch tripped by a servo to ground the coil to kill the engine. I've got both setups, but only one coil engine.

It is a battery! It's 6 volts, and it seems to be fine. I may replace it before I go to fly though.

The airplane is currently setup to only have the manual kill switch on the fuselage. Couldn't I just setup my receiver to have it close the throttle all the way when I flip a switch?

In other news, I got the OS 120 to run today! It feels good to know that it works. I plan to work on restoring the biplane first.
What I did was run the engine out of the fuel can rather than the tank. Looks like I'll need to check the clunk and make sure everything is okay in the fuel tank.

 

[Joker 53150]

It is a battery! It's 6 volts, and it seems to be fine. I may replace it before I go to fly though.

The airplane is currently setup to only have the manual kill switch on the fuselage. Couldn't I just setup my receiver to have it close the throttle all the way when I flip a switch?

If the battery isn't too old it may work just fine, but I wouldn't risk an older battery on the receiver.

So what you have will work, although it's not the safest and could lead to a bad accident later on. Here's what *could* happen... Your kill switch is on the fuselage so it's obviously not easy to reach when the plane is in the air or if you need to kill the engine in an emergency. Closing the throttle all the way CAN starve the engine for fuel which will eventually stop it, but I've got at least one gasser that will still draw enough air & fuel to run - although poorly. The biggest problem is if you lose the receiver in-flight that servo can't close the throttle so now you've got a run-away plane. The optical kill switch ($15) is a link between the receiver and the ignition system. If the receiver dies it kills power to the ignition immediately. if you flip the "ignition kill switch" that you can program on your receiver it does just that. An LED shows you if power to the ignition is on or not, so you can flip the prop to prime without worry that it might accidentally fire up on you. This also lets you run a 6V battery to the ignition and a separate 5V or 6V battery for your receiver (depending on what your receiver and servos can handle). Even though the optical kill switch is physically connected to both batteries there is no shared voltage, only a beam of light inside the switch that cuts power to the engine, kind of a cool idea.

Basically, the optical kill switch is cheap insurance that I 100% recommend and use on all of my gassers.

 

[Chuppster]

If the battery isn't too old it may work just fine, but I wouldn't risk an older battery on the receiver.

So what you have will work, although it's not the safest and could lead to a bad accident later on. Here's what *could* happen... Your kill switch is on the fuselage so it's obviously not easy to reach when the plane is in the air or if you need to kill the engine in an emergency. Closing the throttle all the way CAN starve the engine for fuel which will eventually stop it, but I've got at least one gasser that will still draw enough air & fuel to run - although poorly. The biggest problem is if you lose the receiver in-flight that servo can't close the throttle so now you've got a run-away plane. The optical kill switch ($15) is a link between the receiver and the ignition system. If the receiver dies it kills power to the ignition immediately. if you flip the "ignition kill switch" that you can program on your receiver it does just that. An LED shows you if power to the ignition is on or not, so you can flip the prop to prime without worry that it might accidentally fire up on you. This also lets you run a 6V battery to the ignition and a separate 5V or 6V battery for your receiver (depending on what your receiver and servos can handle). Even though the optical kill switch is physically connected to both batteries there is no shared voltage, only a beam of light inside the switch that cuts power to the engine, kind of a cool idea.

Basically, the optical kill switch is cheap insurance that I 100% recommend and use on all of my gassers.

It sounds like a good failsafe to have. I'll look into it.

Do most people run 6v NiMh batteries for the receiver, or do they use a BEC and a lipo?

 

[Joker 53150]

Either will work, or you could also run a 6V LiFe receiver battery.

 

[Bricks]

As my NIMA and NiCad`s get old I am changing them over to the LIFE batteries. They do not self drain from sitting between trips to the field and hold higher voltage as the pack gets drawn down.

 

[Chuppster]

Yesterday I cleaned out the carb on the FPE. It had a rather thick blockage in the screen.

I cleaned it out and it was able to draw fuel. So, I began trying to start it, but I believe my needle settings were off because it wouldn't run well or for very long. At that point I put it away as it was beginning to get to be late. I hope to try again today!

 

[Joker 53150]

Did you replace any of the gaskets or diaphragm in the carb? I'm planning to re-build my gas carbs every couple years as a preventative measure since we run crappy reformulated gas around here which deteriorates the gaskets. The diaphragm can also stiffen up over time keeping it from pumping gas properly. Most rebuild kits are about $8 or so for everything you'll need and the total rebuild takes maybe 15 minutes. I'll also blow compressed air through the passages once the needles and other parts are removed to make sure there are no bits of junk remaining.

 

[Chuppster]

Did you replace any of the gaskets or diaphragm in the carb? I'm planning to re-build my gas carbs every couple years as a preventative measure since we run crappy reformulated gas around here which deteriorates the gaskets. The diaphragm can also stiffen up over time keeping it from pumping gas properly. Most rebuild kits are about $8 or so for everything you'll need and the total rebuild takes maybe 15 minutes. I'll also blow compressed air through the passages once the needles and other parts are removed to make sure there are no bits of junk remaining.

The diaphragm didn't seem too bad. Where can I find a rebuild kit?

Also, could part of my problem be that I don't have a muffler?

 

[Joker 53150]

You need to determine which rebuild kit you need based on the model number of the carb. There should be some numbers stamped or etched on the carb somewhere, along with a manufacturer name. Then google that info for the proper rebuild kit. Fairly easy to do and there are plenty of videos on YouTube showing the process.

Not having a muffler will probably change the final tube of the carb but it would still probably run. I had a muffler fall off in flight and the engine still ran well. If it wouldn’t start I’d lean more towards lack of fuel in the cylinder which may be carb tuning or the carb needing a rebuild. Especially if you’re turning it over with an electric starter! Hand propping can easily take much more effort to start a plane even with a good carb tube.

 

[Chuppster]

You need to determine which rebuild kit you need based on the model number of the carb. There should be some numbers stamped or etched on the carb somewhere, along with a manufacturer name. Then google that info for the proper rebuild kit. Fairly easy to do and there are plenty of videos on YouTube showing the process.

Not having a muffler will probably change the final tube of the carb but it would still probably run. I had a muffler fall off in flight and the engine still ran well. If it wouldn’t start I’d lean more towards lack of fuel in the cylinder which may be carb tuning or the carb needing a rebuild. Especially if you’re turning it over with an electric starter! Hand propping can easily take much more effort to start a plane even with a good carb tube.

It needs a spinner so I can use my electric starter.