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bob-d.
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May 23, 2016 at 12:24 am #4339
I don’t have any manuals for this motor so your advice would be appreciated. At most, I can get this motor to run for a second or so. It has very strong spark. I have cleaned the carburetor and noticed the float has dried up a little (I think) but I took some fuel proof dope and re-sealed it, but not sure if that made a difference.
This is what is happening. After turning on the fuel and watching the float needle rise up through the hole in the top of the bowl cover, I then turn the needle adjustment on the carb to rich and start pulling the rope. After about 5 or 6 pulls of nothing happening, I check the plug and it seems wet to me.
I notice the carb is dripping as well but and am wondering if the float and needle is not working and fuel is coming out the hole for the needle and running down the side..I then turn off the fuel and start pulling the rope again. As I do this, the float needle starts to move down back into it’s little hole. At this point I can get the motor to fire or even run for a second.
I have submitted a WTB ad in the classifieds for a float and needle.
My question is, could there be another issue causing this motor to not run? If so, what areas do I look at.Your advice is appreciated.
Thank youMay 23, 2016 at 2:37 am #36998It sounds like the float level is off. You will see a groove in the float needle and the float retainer should be there at that level. You may also need to re coat your float so it has better buoyancy.
May 23, 2016 at 3:25 am #37002Thank you Zephyr
I re-coated the float twice and I do have it set at the groove you mentioned. it did not change the issue. Hopefully someone has a float and needle for sale.May 23, 2016 at 4:22 am #37005How is the compression?
May 23, 2016 at 10:42 am #37009Bill, you may have the adjustment needle open to far. If I remember correctly, mine runs at around a quarter turn [or a hair more] from gently seated. There is also a lift spec for the poppet valve… this refers to the amount the poppet valve is allowed to open. There is a cork ”stop” that the poppet valve bumps in to that could also be worn out. At the moment I don’t recall the correct adjustment spec….. Gary will know when he see’s this. It may also be possible to ”lap in” the float needle if it’s not sealing correctly, however, if it’s its grooved to bad it will need replaced.
One other thing I can tell you, is those little carbs have a tiny fuel passage after fuel leaves the bowl, then travels through the passage exiting the carb from a tiny hole when the poppet valve opens. Clean with carb spray followed by compressed air to be sure their open.
May 23, 2016 at 12:37 pm #37014I would go with what Jerry said above regarding lapping the needle. Try that first. It sounds as if the needle isn’t sealing when the cork floats up, causing the motor to flood. You have to use a mild abrasive such as Bon Ami,Cloverleaf 320,or Bar Keepers Friend. Unfortunately I think you are going to have a tough time finding a new needle.
Bob DMay 23, 2016 at 1:34 pm #37018A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.
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This reply was modified 6 years, 9 months ago by
Tubs.
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This reply was modified 4 years, 6 months ago by
Tubs.
May 23, 2016 at 10:35 pm #37037Thank you all for your responses. First let me answer your questions.
1) I have lapped the needle seat with some valve grinding compound. Seemed to have no effect. Maybe I didn’t do it enough.
2) I have tried adjusting the needle valve from fully closed to 1 turn open in increments and it also did not seem to change anything.
3) Compression is at 65PSI
4) there is cork at the top of the poppet valve that does restrict the amount that the valve opens but as you mentioned, we don’t know what the spec is for that. The cork top does NOT appear to be in bad shape and does not look dried out.
5) the passage from the float bowl to the poppet is clean. I will look for a small hole on the poppet as you mentioned to make sure that is clear.I also noticed there does NOT seem to be a fiber washer in the needle adjustment. Should there be? Should there be 2 or one?
May 24, 2016 at 12:00 am #37040Check your float to see how well it floats. Use a bowl & fill with gas. Use a straight pin & float the assembly. Does it float at a level plane? Also use valve lapping compound. It is a tad finer grit for machining. You should set the float turned upside down seated at a level plane, then set the max drop where it doesn’t hit the carb body. Take a piece of hose & attach to the fuel inlet of the carb. Hold the carb upside down & blow slight pressure thru the hose. The weight of the float should seat the needle where no air can be blown out. If leaking use more lapping compound for a better seat. Use a bright light & look inside the seat for the needle. I have run across broken needle tips in the carb seat area. They are hard to get out. Use a little heat to open up the seat & drop the needle out by smacking the carb body against something solid like a 2 x 4 to get it to come out.
Good luck & hope no broken needles are found.May 24, 2016 at 9:51 am #37053There has to be some sort of packing washer around the mixture adjustment valve. Without it, that engine won’t run, because of the vacume leakage around the shaft of the needle. That may be your fuel leak that you see. Maybe you could bench test the carb, to see if it floods? Try removing carb completely from the motor. Hook up a fuel supply to it, maybe with a flexible line with a clamp, or take off the tank and thread the fuel line on to the carb. Any sort of gravity fed [small in size] fuel supply device will work. Now, when you turn on the fuel you can watch for flooding. Check around where the poppet valve seats. If memory serves, I believe the poppet valve must seal completely, or you will see fuel [flooding] seeping out of the teeny tiny hole that i mentioned above. If you think about it, when you move the mixture knob to ”prime”, you are pushing down on the float needle, while at the same time holding open the poppet valve. This gives a little extra fuel drip directly into the intake of the engine, for the extra fuel for cold starts. I’m thinking that you may be flooding the engine if the poppet valve is allowing fuel to escape when it shouldn’t be. Does this make any sense?
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