What needle valve settings are you SPE26 owners using? The manual says 2 turns out on high needle, 1 3/8 turns out on low needle, but these settings seem too lean. I am all garbled up trying to find a good combination of settings, and your helpful input would be much appreciated. What worked for you?

Here we go again

Every engine, altitude, weather, prop, fuel mix combo is different. The needle settings provided by a manufacturer are for getting the engine started only, not for general flying. You have to adjust the needles for your location. The manufacturer does not know where an engine is going to finally end up and cannot tune for that location. There are no factory settings suitable for actual flying. Other peoples' settings are only right for them and are highly unlikely to be right for you and yours.

The manufacturer settings is a starting point for you to work from. It sounds like you need to richen things up, and that takes some experimenting to find the right spot for your installation and location.

Per the manual

High speed needle - 2 turns from closed (±1/4 turn in winter)

Low speed needle - 1 3/8 turns from closed (±1/4 turn in winter)

Every experianced guy will tell you that the factory setting are just a starting point. That is what they are. You will get the engine to crank but you will have to tune the enigine for your specific situation. At first I just wanted my gassers to crank up and fly. Heck my weed wackers ran perfectly out of the box for years with no adjustment. I tried to carry that rational over to my plane engine. You just have to tinker with it till you find the sweet spot. Your best bet is to find someone who had experiance with gas engines and ask for help. That is what got me over the hump.
I have been flying a Giant Aeromaster with a G-62 on it for about a month and I still don't have it running like I want. Sometimes they tune real easy and sometimes they take a bit of patience.

Thanks, all. I just wanted to know if anyone found the factory settings to be close to reasonable. My high end runs better at a full 3 turns out, and the low end is still a mystery to me. Time to take it to a more experienced user, I surmise...

What is it doing exactly?

Yes, what is it doing?


I had a leaky manifold gasket on mine. Because I've always had things to bits since about 7 (ask my dad about the wall socket and the horseshoe magnet - 240V !) I checked it all before I ran it. The gasket was split because the screws were loose. The engine is very good apart from very soft gaskets.

here

a very good site I found for tooning a walbro carb so that it doesn't 4 stroke that way it runs smooth at all rpm ranges from Idle to full throttle the site is "RC aerobatics page"

I tuned an SPE 26 for a guy in Oregon this past weekend. With that particular engine, a few hundred feet above sea level and 70 degrees, it wanted to be about middle of the road for most Walbro carbs. Meaning the low was about 3/4 to a turn out with the high needle a bit richer. It was not a consistent runner and was very sensitive/jumpy about idle trim adjustments. Ran pretty good overall though.

Well i found this web site and i'm sure alot of people already know about it but this is what i have been going buy, and has worked out pretty good..

http://tech.flygsw.org/walbro_tuneup.htm

But now i have to rebuild my carb it looks like on my SPE 26CC engine. but i guess thats what get for running it in a dirt field, keep the dirt out it will kill your carb then your engine wont run..[&o]

the engine isnt even broke in yet i can see the cross hatching on the wall of the cylinder. when i removed the muffler i looked in there to see if it was scored and its not. still clean inside but not broke in yet. it had 5 good flights on it but the carb got pretty dirty flying off a dirt runway and now it wont run.. So if you fly off a dirt runway make sure you check it after flying and clean it.

Currently this is the issue that i have found with mine.
problem: the fuel leaks back into the gas tank when it isn't runningpossable solution:Bad fuel pump membrane, or an air leak in the fuel line at the carb And its not the fuel line leanking unfortuantly.

been awhile since i have rebuilt a carb hopefully it will run better then it did before, or it will at least run again..

Probably just need to replace a couple of easy access parts inside the carb and adjust the metering needle height. No worries, it's an easy job. While you're inside the carb use the manual to locate the filter screen and clean that. Before you fly it again install a high quality gas filter inside the gas tank or inside the gas can. I prefer both but make your own choice here. An air filter can be a fairly simple addition to a carb. Run down to a saw and mower shop and see what they have in the parts bins that you can adapt to fit. It doesn't have to have a fancy mount, just something that will keep it attached and not permit dirt to leak around the edges.

It's rather interesting that the vast majority of gas engine modelers filter the air better on their lawn and garden equipment than they do with their planes. They can buy a new mower or weed eater cheaper than they can the gas engine for their planes but the plane does not have an air filter. Go figure.