ST Bluehead 60
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One of the guys in the club gave me a Chaos with a ST Bluehead 60. It had not been ran in about 10 years so it was a little gummy. I oiled it up and cleaned it well and it fired up and ran ok with the mid range a little rich. I took it to the field and as you know, the gremlins got to it and now it will not maintain an idle after it has warmed. When the engine is cool it will idle fine but after about 30 seconds of running no matter how rich or lean the low speed needle is it will not idle. It just dies. Am I correct in thinking that it is time for a new ring? Also at full throttle it is blowing so much smoke that mosquitos for about a mile radius will disappear. I am getting about 13.5 with a Zingali 11x7 and Omega 10%. Is this good? Bad? My Rossi 60 betters this by about 1100 RPM on the same fuel. Also, is this what is known as a loop scavenged engine?
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I have had no experience with your engine but a-lot with many two cycles. Were it my engine I would disassemble it. Take the ring off the piston and push it down the bore, (with the head of the piston to make sure the ring is square in the bore), to the point it would be at at top dead center, measure the ring end gap with a feeler/blade and do the same with the ring at the bottom of the stroke. This way if you obtain two differnt end gap readings you'll know that your bore has a taper worn in it (doubtfull). I have no idea where you would find the information on the correct ring end gap. Perhaps another member would know. I would make sure that you have no crankcase leaks and if in doubt apply some Permatex High-Tack gastket sealer to the suspected gasket. I would then disassemble the carburetor and soak it in lacquer thinner for a couple of hours. Be SURE to remove any and all "O" rings, rubber seals and gaskets as lacquer thinner will destroy them. While the carb is apart I would run acetylene welding torch tip cleaners (avoid plain pieces of wire which could damage the jet orfices) through all of the jet orfices, blow out the pieces with compressed air if you can and reassemble.
Hmm, that's all I've got. I wish someone would give ME a free engine, cheeze! Anyone have an Enya four cycle they want to part with?
Good luck.
Bill
Hmm, that's all I've got. I wish someone would give ME a free engine, cheeze! Anyone have an Enya four cycle they want to part with?
Good luck.
Bill
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I have done all of the above. I pulled the backplate off and everything looked good. I have tried different plugs as well. Even with the glow driver attached it will still die. I replaced all the lines in the tank and there are no leaks. Could there be an air leak in the engine? Should I seal up everything?
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I'd replace the rubber O-ring between the carb and case. These always get hard and brittle over the years. Without a good seal that can cause tuning issues. Also, where is the tuned pipe? You probably aren't getting enough back pressure for a good idle from that open header. Either bolt on a regular muffler, or attach the pipe.
David
David
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I did replace the O ring at the base of the carb and I do run it with a pipe. The pipe mounts to the wing and I have to remove the pipe to get the wing off. Considering that the engine has many, many hours on it I think I will try a new ring. My thinking is that when it gets to running temperature the expansion of the sleeve is not creating good compression, thus there is not enough "vacuum" to draw fuel up into the combustion chamber. Does this sound logical?
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If it was run on castor oil fuels before, the piston ring may just be stuck in its groove, I've had this happen with K&B .61's also. Carefully remove the ring and clean out the groove with alcohol and a stiff nylon brush.
The case looks like a loop scavenge type, it may have the PDP ports, or TST porting? You might have to remove the head and look down into the sleeve.
Mike
The case looks like a loop scavenge type, it may have the PDP ports, or TST porting? You might have to remove the head and look down into the sleeve.
Mike
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Thanks Mike, I have not considered that. Considering the age of the engine I went ahead and ordered a new ring from Frank Bowman. Thanks again guys.