RCGF 26cc won't draw fuel
07-30-2010, 07:56 AM
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RCGF 26cc won't draw fuel
Hi guys, I have an RCGF 26cc engine mounted on my ESM Stuka. This is my first gasser and I'm having some trouble getting it to start. I've narrowed it down to the fact that the carb will not draw fuel at all. I can get the feed line full of fuel by pulling it off the inlet barb on the carb and letting gravity fill it. However, once I put the line back on the carb there is absolutely no pumping. I can flip the prop forever and the small air bubbles in the line don't move even slightly. I cleaned the primary filter screen with compressed air with no improvement. I'm planning on backflushing the smaller screen that feeds the needle valves this afternoon to see if it helps. I also replumbed all the tank lines to ensure that there were no leaks. Does anyone have any ideas that might help?
07-30-2010, 08:59 AM
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RE: RCGF 26cc won't draw fuel
The carb pump diaphragm is probably U/S.
Get a carb kit (preferably pre-installed in a complete genuine Walbro carb) and change it out. If you use the original carb, while it is in bits, clean out all the passages and check the reeds and reed block for accuracy while you are there - might save you needing to do that later on.
Get a carb kit (preferably pre-installed in a complete genuine Walbro carb) and change it out. If you use the original carb, while it is in bits, clean out all the passages and check the reeds and reed block for accuracy while you are there - might save you needing to do that later on.
08-01-2010, 08:22 PM
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RE: RCGF 26cc won't draw fuel
Well, I regasketed the carb and blew the thing out quite well with carb cleaner and compressed air. It initially seemed to draw fuel better but still isn't enough to fire the engine. I ordered a new carb hoping that fixes that problem.
08-02-2010, 07:23 AM
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RE: RCGF 26cc won't draw fuel
I cant get my new RCGF 26 to draw fuel either. My two DLE's w/ Walbros, no problem. I see its not a Walbro like its advertised. At least Walbros not stamped on it like the DLE's carb. I willl be curious if the new carb fixes your problem. I'm gonna try t.o.m. suggestion.
08-02-2010, 08:51 AM
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RE: RCGF 26cc won't draw fuel
I have had mine for over a year now and it never would draw fuel by hand. I tried all the fixes and checks and nothing. I finally gave up and used an electric starter. It will fire pretty fast with it. Even after it has been running it will need a starter if it has sat longer than an hour or so. Yes, it runs with an 18x6 xoar at about 7500 rpm if I recall correctly. Its in a 1.20 size spacewalker. It can barely get out of its own way in that plane. The guys at the field love it, its just not my cup of tea.
Stangevil29
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08-02-2010, 08:55 AM
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RE: RCGF 26cc won't draw fuel
My RCGF 26 has a small hole in the choke plate. I have soldered it up and now it chokes in a few flips , perhaps yours is the same?
08-02-2010, 09:12 AM
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RE: RCGF 26cc won't draw fuel
Thanks. I saw they sell it, just couldnt tell if it was in stock. I ordered anyway. The carb on my 20cc failed on me after a gallon. Really weird. It started out intermittant, then wouldnt get past half throttle without quiting. I could remove and clean the carb and it would work fine for a couple of times, then the same problem again. After 4 times of that routine, I sent it in for warrenty. Came back no problem found. When I got it back, it ran fine for one time then failed completely, no start. I replaced the ignition, sensor, reed valve, same problem. Took it out of the plane and mounted on test stand and primed a little through the carb, it would run on the prime, but thats it. Spark plug is dry, not getting fuel. I can take the carb apart and see fuel in the regulator diaphram and pump flappers, just no fuel getting through the carb throat. Fuel is pumping, I can see fuel travel from the tank up to the carb while spinning the prop with my starter. Never seen any crud in the screens. That carb has been flushed, cleaned, vibrated in my sonic bath many many times. I'm stumped. So a new carb it is. This engine will not beat me, I will prevail!!![>:]
Edwin
Edwin
08-02-2010, 10:47 AM
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RE: RCGF 26cc won't draw fuel
ORIGINAL: awesome
My RCGF 26 has a small hole in the choke plate. I have soldered it up and now it chokes in a few flips , perhaps yours is the same?
My RCGF 26 has a small hole in the choke plate. I have soldered it up and now it chokes in a few flips , perhaps yours is the same?
08-02-2010, 12:29 PM
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RE: RCGF 26cc won't draw fuel
I plugged the hole on the choke plate too but it didn't do a darn bit of good.
Is there a real Walbro carb that will fit these engines?
Is there a real Walbro carb that will fit these engines?
08-02-2010, 01:33 PM
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RE: RCGF 26cc won't draw fuel
My friend just gone one of these, but has not tried to start it. I did notice that it uses an external pulse line from the engine crankcase to the carb. Since that pulse is necessary to pump fuel into the carb, maybe check to be sure it is not clogged and is actually providing a pulse.
Regards,
Richard
Regards,
Richard
08-02-2010, 01:48 PM
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RE: RCGF 26cc won't draw fuel
Thanks for the suggestion. Verified and reverified. I even replaced the line with higher quality tubing to make sure it wasn't collapsing.
Anyone have an idea for a genuine Walbro carb that will fit this engine? I'm going to go by the small engine shop today and see if I can't find something.
Anyone have an idea for a genuine Walbro carb that will fit this engine? I'm going to go by the small engine shop today and see if I can't find something.
08-02-2010, 02:49 PM
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RE: RCGF 26cc won't draw fuel
I'm looking for a walbro carb too. A long time ago I had a chart that gave specs like carb bore diameter, number of needles, choke/no choke, and so on. Naturally I cant find that. I heard a guy used a WT411 on a 20cc and it worked fine (after making an exteranl pulse connetion for it). But that carb is no longer available. The closest I can find for a 9.5mm bore is WT318, WT227, and WT264-1. I'm trying to get more info on them as far as specs go. I just want hi and low speed needles, choke, and as close to 9.5mm bore as I can get. I dont really want the prime bulb but I deal with it if thats all I can get. I ordered the chinabro from BP Hobbies but that is only to get by.
iroc,
Do you have fuel at the regulator diaphram and pump flappers? Mine did, but no fuel (or very little) was getting to the engine. Your problem sounds a lot like mine. It would run on the prime, but thats it. If you have no fuel in those area's, the regulator fork may need adjusting. Another test would be to dry out the fuel line to the carb and rock the prop to see if it sucks fuel up to the carb. That will verify the reed and pump pulse. Removing the plug and spinning with an electric starter is the fast way of doing that. FYI - I've heard of a few other guys with defective reeds. They were warped pretty bad. Mine was.
OR, you just have a messed up carb like mine.
Edwin
iroc,
Do you have fuel at the regulator diaphram and pump flappers? Mine did, but no fuel (or very little) was getting to the engine. Your problem sounds a lot like mine. It would run on the prime, but thats it. If you have no fuel in those area's, the regulator fork may need adjusting. Another test would be to dry out the fuel line to the carb and rock the prop to see if it sucks fuel up to the carb. That will verify the reed and pump pulse. Removing the plug and spinning with an electric starter is the fast way of doing that. FYI - I've heard of a few other guys with defective reeds. They were warped pretty bad. Mine was.
OR, you just have a messed up carb like mine.
Edwin
08-02-2010, 05:20 PM
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RE: RCGF 26cc won't draw fuel
ORIGINAL: Edwin
Do you have fuel at the regulator diaphram and pump flappers? Mine did, but no fuel (or very little) was getting to the engine. Your problem sounds a lot like mine.
Do you have fuel at the regulator diaphram and pump flappers? Mine did, but no fuel (or very little) was getting to the engine. Your problem sounds a lot like mine.
It won't even pump fuel up to the carb now. Useless.
I found a used WT-311 carb at the small engine shop. I'm going to rebuild it and use it keeping the spare RCGF carb in reserve.
08-02-2010, 05:49 PM
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RE: RCGF 26cc won't draw fuel
According to the listing one post up the 311 is a 6.5mm venturi. Might be a bit small.
Lots of good info posted above. Just wish I could search with perameters. This is gonna take some time. But I did find some interesting prospects.
Edwin
Lots of good info posted above. Just wish I could search with perameters. This is gonna take some time. But I did find some interesting prospects.
Edwin
08-02-2010, 06:23 PM
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RE: RCGF 26cc won't draw fuel
Well men, I attached my electric starter to my 19.2V cordless drill batteries and spun the engine over with it. It began drawing fuel. I choked the life out of it and then opened the throttle and it fired right off. I'm pleased that it runs, but I'm not thrilled that I have to use a starter to get it to fire. I'm still going to try the new Walbro carb and see what that gets me.
08-02-2010, 08:19 PM
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RE: RCGF 26cc won't draw fuel
Irocbsa try pulling the metering diaphragm cover off and veryslightly pull(bend)the metering lever up a littleallowing the metering needle to open more. This will allow more gas to be pulled into this side of the carb......and will more than likely solve your problem. My dad and I have had to do this to my DA50 and a Zenoah 20 he had. Hope this helps!
08-02-2010, 09:59 PM
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RE: RCGF 26cc won't draw fuel
Try this take the spark plug out and squirt some gas straight into the cylinder and re install the plug and try and start the engine it will most likely fire up for a few seconds and quit then just repeat the proses until the engine stay's running should take about 4 try's if not than your high end is not open enough
hyflyer9
hyflyer9
08-02-2010, 10:30 PM
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RE: RCGF 26cc won't draw fuel
That's another one of those "been there done that" situations. 
That helped for a while but it stopped responding to the spark plug trick. It took a good 10 seconds with the starter to get it to fire, and that's after the fuel reached the carb inlet.
That helped for a while but it stopped responding to the spark plug trick. It took a good 10 seconds with the starter to get it to fire, and that's after the fuel reached the carb inlet.