predator500

My Feedback: (1)

^Thanks a lot, I thought opening the reed in the first place was kinda odd. Ill do that tomorrow and hopefully get it all started by Tuesday.

And one more question, the primer bulb, when connected, will allow fuel to pass through it from the tank correct? I tried sucking fuel through the feed line that came from the bulb via fuel pump and nothing happened, thinking that might have been my problem. I do want to have the primer bulb on the plane as its cowled, but is that supposed to happen?

flyjoe540

I dont know for sure I dont use it on mine. the choke is all I have needed , but you need to fill in the hole in it with solder or jb weld .then it will really suck (in a good way) the fuel. I think the primer bulb goes on the other nipple on the carb and just dumps fuel into the carb, I dont think fuel will flow through it because of the check valvein it.

predator500

My Feedback: (1)

Wow, if thats true then I have some re plumbing to do. Im going to run it without the bulb for now, but it'll take like 30 seconds to put it in its right location. And yes, I will fill up that hole with JB weld when I take the engine off (again). Also, Im going to build a test stand for this thing because taking it off and putting it on the airframe is combursome and frequent currently. Well, atleast I know what to do now in the future! Thanks again guys.

captinjohn

I could be wrong...but what people call a primer bulb is really a purge bulb. It gets fuel to carb and pushes the air out of the system and back to the fuel tank. It really does not get fuel inside the engine like a choke will. In other words you do not need any bulb at all. I may get some feedback...on this one!!!!! Capt,n[:-]

predator500

My Feedback: (1)

Well I replaced the reed valve, threw my engine together and fired her up! It was kinda cold here, plus it was after dark and I didnt want to wake up the neighbors kids, so I only started it and let it warm up a bit. It runs great and sounds awesome too! Hopefully I can get it all tuned up and stuff and ready for her maiden. I think Ill take some video Thursday night, so Ill post it here for you guys! Thanks again for all your help, I couldent have done some of this stuff without you guys.

Colin C

captinjohn

I had a pretty good hunch that the reed valve was the cause. Glad you got her purring now. Capt,n

predator500

My Feedback: (1)

Haha yep, but I will tell you, its one of the best learning experiences I've had so far, and Im really glad it turned out alright!

flyjoe540

congratulations ,let us know what kind of numbers you are getting .
good call capt!

captinjohn

Hey us Mich-i-ganders are on top of stuff. Right now a lot of white stuff.....SNOW!!!!! Capt,n

captinjohn

Hey Guys....Would a strong 31cc Ryobi work good in this plane? http://www.rcuniverse.com/forum/m_51...tm.htm#5195703 Thanks Capt,n

predator500

My Feedback: (1)

I dont know, I think Im pushing the Ryobi's power as it is in my Cap, and it weighs 2 pounds lighter then that airplane you mentioned. Its up to you though...

captinjohn

I was trying to help the other guy that has the 330L because he had no replies. But I was kinda interested too! Capt,n

predator500

My Feedback: (1)

Well tonight I tried tuning and running my engine, but Im having problems. It will sit and idle forever, but I cant advance the throttle at all or else the engine dies. It doesnt matter how fast or slow I throttle up, it just quits. I tried messing with the low end needle but it didnt help much at all, I dont know what the problem is. The fuel lines dont have any leaks and there is no air getting into them and into the engine via leak. Im not really sure what to do here, any ideas?

Oh and I have a new addition to my engine family, a Homelite 25cc! I have the entire powerhead, so I started it up and it runs great. Should make a really good second conversion, now all I need is a plane (or swap out the Ryobi) to put it on!

Colin C

captinjohn

Predator500: It sounds like the Hi speed circut is plugged. Make sure all passages are clean. I use carb cleaner with the little red tube and inject into hole that hi speed needle goes in. Then blow out with compressed air. If you put jb weld in the primer fitting on the carb..maybe some got where it is plugging carb up? A good plug is a short piece of fuel line with a rivit pushed in it. Capt,n

predator500

My Feedback: (1)

I ended up putting the primer bulb on the carb and have never used JB weld on the carb so I dont think thats the case. Im going to try and clean out the high end needle like you said and if Im still having problems, Im going to switch over to the Zama I have off of the other Ryobi. Hopefully my Walbro will be fine and only need a bit of cleaning, and I will go back around and make sure all my fittings are sealed correctly. I put some nicrome wire around every fitting today, but I will recheck all of that.....Thanks for the help!

predator500

My Feedback: (1)

Sorry to keep bringing back a dead topic, but I have yet ANOTHER setback.

So when I was test starting my engine, I would just leave the choke on and let it idle a bit. Now, Im taking the choke off and trying to break it in. This is where it gets funky. The engine will idle around 1000 RPM (just guessing, I dont have a tach) with the choke on. As soon as I take it to half choke, it jumps another 1000 RPM I'd say, which is awfuly fast for idle (more like 1/2 throttle) and once I take it off the choke completely it jumps to around 4000 RPM. I cant control the throttle at all, and if I try to pull it off, naturaly it dies, and sometimes it dies when Im not even touching it. There is just simply no throttle response and it idles WAY to high, and Im not sure what the problem is. I might try and put the Zama on tonight and see if that helps at all, but I dobut it. Does anyone know what the problem might be?

Also, as a side note, I took the engine head off of another Ryobi and put it on the "good" engine because one of the muffler bolts was stripped. I looked at the two heads side by side and immediately found my compression problem. In the piston sleve on the head I was using were two grooves that were about 3/4 the length of the way up, the replacement head did NOT have these and has a lot better compression! I did run it with both heads and both are having the above problem, so I would cancel that out. But anyways, thats about the jest of it. Thanks for the help!

Colin

tstotts

Colin sounds to me like you have an air leak somewhere in your fuel system. Can be anywhere from the carb gasket to a loose or cracked fuel line.

predator500

My Feedback: (1)

Thats what I thought too, so I replaced all the fuel lines and gaskets on the entire engine. I just went to go try it out and still the problem exists. Im starting to think that its more of a fuel supply issue, because it will sit and idle all day with the choke on, but at half choke it eventualy dies and a no choke it quits within 10 seconds. I switched to the Zama carb and it did the exact same thing as the Walbro carb did. Im just not sure what the problem is! It just seems like as soon as the fuel flow is more "demanding" for lack of a better word, the engine just quits! Ill have to take some video later and show you guys so you can see for yourself whats going wrong...

captinjohn

Try to test the crankcase and front seal with a very slight pressure to crankcase. Remove exhaust and clean outlet and tape shut with ducktape. Remove carb and you will see a small hole next to where carb goes. Apply a slight pressure in that small hole with a tube. Next while blocking off where carb attached with a cork, or your thumb..... squirt bubble water on all joints and seals. If there is a leak it will show up. Hope you understand this. Do not have the pressure over 1-2 pounds or less. Capt,n

mikenlapaz

I would check the sealing surfaces between the carb and backplate of the engine. Seal off the exhaust, put some air pressure into the main air inlet of the carb, use some soapy water to test for air leaks.

flyjoe540

pred
where do you have your needles set at ? is it a stock carb?

predator500

My Feedback: (1)

^Yes its a stock carb, and I was actualy thinking that it might be too lean from factory settings....just an idea.

I'll try out all the gaskets and seals like you guys mentioned tonight, and if I remember correctly, I think that I heard a leak where the plug screws in, so I tightened it down and I think it went away, but then again, I didnt have a leak there on the other engine....

This is a mystery haha.

flyjoe540

make sure your needle(s) are open two turns to begin and tune it from there . it sounds like it is either not getting enough fuel , or there is a vacum leak , which wont power the pump diaphram. which means no fuel .

another good way to find a vacum leak is to spray carb cleaner at the suspected leaky joints and listen to the engine as it runs .when it sucks the carb cleaner in the rpm will go up . just dont do it with a prop on it , cut down a broken prop to use as a spacer . then use an electric starter to turn the engine over .

av8tor1977

My Feedback: (6)

If the carb has the original settings, it is definitely set too lean. When you remove the air cleaner and provide a more free breathing exhaust, that automatically leans the mixture from the already fairly lean factory settings. Open the high speed needle at least one full turn and and the low speed about a half turn and try again. If everything else in the system is sound, that should let it rev up, and possibly be a touch rich. You can fine tune from there.

AV8TOR

predator500

My Feedback: (1)

Well I have some GREAT news, the engine is fixed!!!!!!

I thought I had tried everything, and the problem was something that had been discussed on the first page.....can you guess what it is? Yep, the fuel line!

I went to the hobby shop today and picked up some Tygon line because the fuel line I had was getting stiff. I threw it on the engine and it ran perfectly! I think that maybe the line was not providing the engine with enough fuel due to its size after it shrunk, but anywho my problem is solved.

Thanks to all of you guys out there that helped me with this, I REALLY could not have done it with out you! Next project, a Homy 25cc... Look for a help thread shortly!!

Video link: [link=http://www.youtube.com/watch?v=P6eQ-PmQEUQ]http://www.youtube.com/watch?v=P6eQ-PmQEUQ[/link]