ST 51
02-03-2008, 05:16 AM
#51
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RE: ST 51
The pope here with update no 2. I went to the field today with the 51 installed in my PC 9 , all went according to plan besides the 2 screws holding the brass spray bar coming loose ( funny how the same 2 screws in my nib 90 were loose as well ), anyway the leak has almost completly stopped. It now appears to be a slight leak comming from the nut area that holds the ratchet spring on but looking at the carb diag. this seams a long shot. Anyway I might pull the carb apart and give it the once over but I have a sneaky suspicion that the needle valve is still the problem, maybe if bax is lurking around he would like to put his 2 cents worth in. Cheers the pope
02-04-2008, 11:31 AM
#52
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RE: ST 51
ORIGINAL: Flyboy Dave
Bax....what do you think about mine, with the main needle spring in the barrel, and
the o-ring at the bottom of the HS needle.....mis-assembled ?
Bax....what do you think about mine, with the main needle spring in the barrel, and
the o-ring at the bottom of the HS needle.....mis-assembled ?
Pope: Fuel collecting on exterior parts of the carburetor MAY mean a leak, but it can also mean that some fuel is being 'spit' from the carb and collection on the carb parts. Some fuel will be thrown from the front bearing and collect on engine parts. The reason you will see it on the needle spring and the idle stopper spring is because they give that area some protection from the prop blast and allow the surface tension of the fuel to hold it there until a drop gets large enough. If the fuel accumulating there is only a visible drop, then it's not any kind of problem. If you are getting a lot of raw fuel thrown from the engine and it's getting onto the airframe and almost dripping, then your leak is most likely from the front of the engine and you'll need a new crank, case, or both. The front bearing provides absolutely no seal at all. It's not supposed to. The seal is made by the close fit between the case and crank forward of the carb.
02-04-2008, 12:13 PM
#53
RE: ST 51
I've got a small leak in the high speed needle on my G-2300. Iwas thinking of juscovering the threads with some teflon pipe tape. Good Idea? Not? I haven't tried to dissasemble the needle but I do see the o-ring in the brass holder.....
02-04-2008, 12:23 PM
#54
RE: ST 51
I like all the posts on this thread....its clear people was trying to help. Also one has to remember there are many others the photos will help. If not right now...sometime down the road. Thanks people for taking the time. P.S. I have run tigers for years...and have most all the data that came with em. Best Regards Capt,n
02-04-2008, 09:27 PM
#55
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RE: ST 51
ORIGINAL: Bax
There should always be a spring inside the high-speed needle's barrel, with a very small o-ring towards the outside. If a spring was missing from a new carb--misassembled. If missing from a used carb--possible loss by the previous owner.
Pope: Fuel collecting on exterior parts of the carburetor MAY mean a leak, but it can also mean that some fuel is being 'spit' from the carb and collection on the carb parts. Some fuel will be thrown from the front bearing and collect on engine parts. The reason you will see it on the needle spring and the idle stopper spring is because they give that area some protection from the prop blast and allow the surface tension of the fuel to hold it there until a drop gets large enough. If the fuel accumulating there is only a visible drop, then it's not any kind of problem. If you are getting a lot of raw fuel thrown from the engine and it's getting onto the airframe and almost dripping, then your leak is most likely from the front of the engine and you'll need a new crank, case, or both. The front bearing provides absolutely no seal at all. It's not supposed to. The seal is made by the close fit between the case and crank forward of the carb.
Thanks bax for your time, now if it is a low pressure area and fuel is just accumulating there what if put a piece of card between the prop and the carb to see if the needle valve is the problem ( I can see some chopped fingers a happenen ) would this be a good idea or not. If all else fails I might use some thread tape and see how this goes. Cheers the pope
ORIGINAL: Flyboy Dave
Bax....what do you think about mine, with the main needle spring in the barrel, and
the o-ring at the bottom of the HS needle.....mis-assembled ?
Bax....what do you think about mine, with the main needle spring in the barrel, and
the o-ring at the bottom of the HS needle.....mis-assembled ?
Pope: Fuel collecting on exterior parts of the carburetor MAY mean a leak, but it can also mean that some fuel is being 'spit' from the carb and collection on the carb parts. Some fuel will be thrown from the front bearing and collect on engine parts. The reason you will see it on the needle spring and the idle stopper spring is because they give that area some protection from the prop blast and allow the surface tension of the fuel to hold it there until a drop gets large enough. If the fuel accumulating there is only a visible drop, then it's not any kind of problem. If you are getting a lot of raw fuel thrown from the engine and it's getting onto the airframe and almost dripping, then your leak is most likely from the front of the engine and you'll need a new crank, case, or both. The front bearing provides absolutely no seal at all. It's not supposed to. The seal is made by the close fit between the case and crank forward of the carb.
Thanks bax for your time, now if it is a low pressure area and fuel is just accumulating there what if put a piece of card between the prop and the carb to see if the needle valve is the problem ( I can see some chopped fingers a happenen ) would this be a good idea or not. If all else fails I might use some thread tape and see how this goes. Cheers the pope
