OS .46 Engine troubles
10-23-2005, 02:00 PM
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OS .46 Engine troubles
My engine wont start unless I prime it. I put a little fuel right in the intake and it then will start after a few pulls. I then put the throttle on full and fuel gets brought through and it runs great on full throttle. Soon as I bring it back down it stutters and shuts off. I cant start it without priming it. What is wrong! Fuel is comming to the engine, spark is obviously getting to it, but why wont it stay running!
10-23-2005, 10:45 PM
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RE: OS .46 Engine troubles
Low speed needle needs an ajustment. Really every time I ever haer my engine won't run right 9 times out of 10 it's cuase they've never touched the low end needle. after the motor is broke in you need to tune the motor
Aright. GEt the motor going and advance to full. Adjust the high end to peak RPM then back off 3-4 clicks. You should hear a slight drop in engine pitch. Bring the motor to an idle. if it won't run at idle get it as low as you can. Now pinch the fuel line for a couple seconds and listen to the motor. If it just stops, the low end is lean. richen it up an 1/8th of a turn. If it speeds up and dies, it's too rich, lean it out an 1/8. Advance to full throttle and reset the high needle. again set it for peak RPM then back it off. Go back to idle. DO the pinch thing again. DO this about 3 even 4 times and it should be a rock solid setting.
If it doesn't
You got leak somewere. get out the vasoline[8D]. um don't go there
anyway take off the carb and spead some of the jelly on the base. take the low end needle and the high end needle and spead some on the threads and o-rings, replace the fuel lines just for spite. Stick the engine in the freezer for about 5 min then tighten up the head bolts evenly I might add and snug the back plate up. Now that your needle settings are all screwed up you get to go through the tune in all over again
A better way to prime the engine. You might not think so since it takes a few more seconds. leave the igniter off advance the throttle to full hold your finger over the exaust and flip the prop until you see fuel go into the carb. Then flip it 3 more times. Close to 1/4 throittle and start the motor. This getts fuel to the motor and adds pressure to the fuel tank
Aright. GEt the motor going and advance to full. Adjust the high end to peak RPM then back off 3-4 clicks. You should hear a slight drop in engine pitch. Bring the motor to an idle. if it won't run at idle get it as low as you can. Now pinch the fuel line for a couple seconds and listen to the motor. If it just stops, the low end is lean. richen it up an 1/8th of a turn. If it speeds up and dies, it's too rich, lean it out an 1/8. Advance to full throttle and reset the high needle. again set it for peak RPM then back it off. Go back to idle. DO the pinch thing again. DO this about 3 even 4 times and it should be a rock solid setting.
If it doesn't
You got leak somewere. get out the vasoline[8D]. um don't go there
anyway take off the carb and spead some of the jelly on the base. take the low end needle and the high end needle and spead some on the threads and o-rings, replace the fuel lines just for spite. Stick the engine in the freezer for about 5 min then tighten up the head bolts evenly I might add and snug the back plate up. Now that your needle settings are all screwed up you get to go through the tune in all over again
A better way to prime the engine. You might not think so since it takes a few more seconds. leave the igniter off advance the throttle to full hold your finger over the exaust and flip the prop until you see fuel go into the carb. Then flip it 3 more times. Close to 1/4 throittle and start the motor. This getts fuel to the motor and adds pressure to the fuel tank
10-26-2005, 10:47 AM
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RE: OS .46 Engine troubles
hi
with engine not running close throttle fully and carefully screw in idle screw until it stops, do not force here. then screw it out about two turns. adjust hi speed as described earlier then throttle down and let engine run for about one minute, then throttle up. if engine then balks and comes up slowly turn idle screw in about 1/4 turn and keep trying until you get smooth transition. if engine quits turn idle screw out about 1/2 turn. continue until you get smooth transition from low to high.
good luck and happy flying
pt19 flyer
with engine not running close throttle fully and carefully screw in idle screw until it stops, do not force here. then screw it out about two turns. adjust hi speed as described earlier then throttle down and let engine run for about one minute, then throttle up. if engine then balks and comes up slowly turn idle screw in about 1/4 turn and keep trying until you get smooth transition. if engine quits turn idle screw out about 1/2 turn. continue until you get smooth transition from low to high.
good luck and happy flying
pt19 flyer
