M-47 sticking float? Fuel flowing..
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M-47 sticking float? Fuel flowing..
M-74 on a 55 runs fine, but often starts dumping fuel-looks like the float needle is open and flowing, dripping-or running out the bowl seam, or above. I did take apart, clean, and inspect. Nothing was obviously sticking anywhere, perhaps worn parts have too much play?
The PO said to rap on the float bowl with a hammer (love POs) Looking at the pics one can see where that technique was utilized for some time. While that might work I am interested in actually fixing the problem.
Known issues? Fixes? Nothing was dirty or broken, and did not seem incredibly loose in there , but that still might be it.
Recommendations? (and, yes, I have a repair manual or 3) Looking for wisdom from those who have crossed this bridge before me.
The PO said to rap on the float bowl with a hammer (love POs) Looking at the pics one can see where that technique was utilized for some time. While that might work I am interested in actually fixing the problem.
Known issues? Fixes? Nothing was dirty or broken, and did not seem incredibly loose in there , but that still might be it.
Recommendations? (and, yes, I have a repair manual or 3) Looking for wisdom from those who have crossed this bridge before me.
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Re: M-47 sticking float? Fuel flowing..
In addition to what the manual says..
Check the float lever. I had an occasion where it was like the pin size was different to the hole in the lever.
I got a Viton tip needle valve in defiance of numerous complaints about them. As I recall some of the criticism was aimed at US gasoline's ethanol content attacking the Viton otherwise folk said they were poorly made and the tips parted company. I fitted mine in 2015 and it's been perfect ever since. I've even accidentally left the gas on overnight without penalty. I would get another when/if it fails. (No ethanol in fuel here.... yet!)
Check the float lever. I had an occasion where it was like the pin size was different to the hole in the lever.
I got a Viton tip needle valve in defiance of numerous complaints about them. As I recall some of the criticism was aimed at US gasoline's ethanol content attacking the Viton otherwise folk said they were poorly made and the tips parted company. I fitted mine in 2015 and it's been perfect ever since. I've even accidentally left the gas on overnight without penalty. I would get another when/if it fails. (No ethanol in fuel here.... yet!)
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Re: M-47 sticking float? Fuel flowing..
check out Pacific Mike on youtube he has a 2 part video on re build and set up of the m74 carb . the needle and float adjustment is critical !
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Re: M-47 sticking float? Fuel flowing..
The needle and seat are new, however I am going to get another as you are right, its still got to be the problem. I also ordered the float assembly and pivot hardware.. Start fresh.
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Re: M-47 sticking float? Fuel flowing..
Second time replacing needle and seat. Still pissing. The float lever seems to be sticking on the needle? I have carefully smoothed/filed to make things smooth. Is there a higher quality needle, seat, and lever than the crap I seem to be buying? I bought this V-twin kit, it has a cast lever that seemed quality, but does not work smoothly. https://www.jpcycles.com/product/400-16 ... e-assembly
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Re: M-47 sticking float? Fuel flowing..
u have to bend the float lever to put more pressure on the needle to the seat . Getting the float settings correct can be a tedious procedure , but worth the effort !
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Re: M-47 sticking float? Fuel flowing..
If you are still struggling, how about setting it up as pictured. Fit a cork in the bottom hole then connect fuel line. Turn fuel on and observe. Use bright light and perhaps #3 bifocals. Let it sit for a minute or so, or drain and repeat.The object is to catch it misbehaving...
Good luck, hope it helps
Good luck, hope it helps
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Re: M-47 sticking float? Fuel flowing..
One problem that you might be having isn't a sticking float valve and seat, but a float hanging up on the carb stem that the bowl attaches to. The float has to be positioned just right. If it's offset too much or not enough, it can catch on the stem, letting fuel pour in.
Here's a fix for this that I learned from Cotten (who used to post here).
With the carb detached from the manifold, remove the float bowl.
1. "Paint" any part of the carb stem with a dry-erase marker.
2. Attach the float bowl.
3. Gently turn the carb over a few times. You should be able to hear the float moving when you do this. If not, the float is likely stuck.
4. Remove the float bowl. If there are any spots where the marker has been rubbed off, or any marker color is on the float, the float is hanging up on the stem. I'm assuming that the float is centered well enough that it isn't hanging up on the float bowl.
5. Adjust the float accordingly, and go back to step 1.
If the float is adjusted correctly -- level and 1/4" down from the bowl rim, you should be able to hear the float move when you rotate the carb up and down each time.
Good luck!
Here's a fix for this that I learned from Cotten (who used to post here).
With the carb detached from the manifold, remove the float bowl.
1. "Paint" any part of the carb stem with a dry-erase marker.
2. Attach the float bowl.
3. Gently turn the carb over a few times. You should be able to hear the float moving when you do this. If not, the float is likely stuck.
4. Remove the float bowl. If there are any spots where the marker has been rubbed off, or any marker color is on the float, the float is hanging up on the stem. I'm assuming that the float is centered well enough that it isn't hanging up on the float bowl.
5. Adjust the float accordingly, and go back to step 1.
If the float is adjusted correctly -- level and 1/4" down from the bowl rim, you should be able to hear the float move when you rotate the carb up and down each time.
Good luck!
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Re: M-47 sticking float? Fuel flowing..
Perhaps your float is to large now. Can you remove the float from the bowl easily or is it tight and need a tug to get it out. Liberty sells a damn nice float.
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Re: M-47 sticking float? Fuel flowing..
Think I have it figured out. I tried multiple combinations of parts and adjustments and it never resolved. All this time I kept using the brass float that was in there, not wanting to change to the synthetic one. There was not a cork float in there, and the kit I bought (V-Twin) did not have cork. The brass one ( in general, I am a fan of brass) seemed functional-however it was in some way faulty, I never detected any fluid in it. I set it up to specs and used the "synthetic" float from a kit and it shuts off fine so far.
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Re: M-47 sticking float? Fuel flowing..
Remember, "Brass floats don't float", and you will be fine. H-D NEVER used a brass float.
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Re: M-47 sticking float? Fuel flowing..
I don't know why it was in there, I didn't put it in. I have had many vintage cars with brass floats, they seem to float just fine