Buddy 125cc - dumps fuel into engine

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atxg3
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Buddy 125cc - dumps fuel into engine

Post by atxg3 »

Hi all - I've got a Buddy 125cc 2012. It's got 5900 miles on it. It did sit for about 3 years before I bought it, however, here's what I've done with it so far. After lurking on here for more than a month and doing all of what I've listed here, I need your help! Here's what I've done:
  • Flushed ALL of the old gas, replaced with brand new gas about 1/2 full after complete clean of carb and new petcock (was broken) + fuel lines
  • Cleaned the carb (complete cleaning with carb cleaner, and fished out all of the debris in all the pipes/tubes using special tools, and confirmed all are completely clear multiple times.
  • Cleaned all of the Jets completely. Idle screw took me nearly an HOUR to finally clean after being completely blocked.
  • Bought and replaced the float needle and float (sits fine now, does not get stuck etc.) although I suspect it worked just fine before as it still runs rich.
  • Had a broken auto petcock so I've replaced it with a genuine one and new fuel tank filter
  • replaced inline fuel filter + hose for the fuel filter (clear hose to see fuel flow)
  • bought and replaced the spark plug
  • cleaned the diaphram needle and made sure of a good seal for the diaphram (confirmed it's a good seat as I've been able to get it up to 55+ no problems)
  • Changed oil and changed gear oil to specs (measured both, and perfect levels)

Now, here's the interesting part. Scooter ran FINE, got up to speed, but was always running a little rich. A few times when going to start it, I noticed the smell of fuel, and once I had fuel spilling out of the air filter box. I removed the spark plug and noticed it was pretty foul (black colored) and let to dry, kick started out a considerable amount of fuel, and replaced after cleaning the spark plug. Scooter ran fine again.

Then one night, I decided to swap out the PCV vacuum line, once I did, scooter would not start. I then replaced the vacuum line, and still no luck. I could see fuel coming down the line, but still no luck. After cranking it for 20 seconds, it would occasionally burst to life, and then immediately die.

again, i could smell fuel, and pulled the spark plug to see it again covered in fuel...

I guess my question is, what would cause my engine to become completely full of gas constantly when starting it? Or cause it to run rich so much?

Can someone speak to what exactly what part of the carb would cause the carb to completely drain gas into the engine?

I am suspecting it still has something to do with the float needle and float itself, so if anyone can share youtube videos/images of exactly how it should look + when tilting the carb, when it should open etc...

I also could not remove the actual gold jet/ring that holds the needle/allows fuel, so could someone let me know if I can remove that and/or if it's necessary to remove and clean?


Thanks all in advance!
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Point37
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Post by Point37 »

did you overfill the tank?...autochoke on the carb working?...float have a hole in it?...needle valve spring installed incorrectly?
'10 Triumph Bonneville SE (sold), '00 Yamaha TW200 (sold), '08 Husqvarna SM510R (sold), '05 Honda CBR 600RR (sold), '03 Honda CBR 600RR (sold)
atxg3
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Post by atxg3 »

Point37 wrote:did you overfill the tank?...autochoke on the carb working?...float have a hole in it?...needle valve spring installed incorrectly?
Thank you for the response!

Did not overflow the tank, had about half a tank currently.

Autochoke does work, I think... I need a multimeter to test, but it works GREAT when first starting, then once warmed up, runs awful and incredibly rich.

Float does not have a hole, I put it underwater and watched for any bubbles to rise, none whatsoever.

Needle valve spring is installed correctly, did the whole 14.5mm measurement when it first lets in gas, completely polished and cleaned the ring it sits in, as well as needle.
atxg3
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Post by atxg3 »

Point37 wrote:did you overfill the tank?...autochoke on the carb working?...float have a hole in it?...needle valve spring installed incorrectly?
Just tested the ohm resistance for the autochoke - 5.8 Ohms
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tenders
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Post by tenders »

My guess would be that the little metal tab that controls the relationship between the height of the float and the position of the float needle is set too LOW, ie, too far away from the base of the float needle - such that there is too much fuel in the float bowl.

I don’t know what the right level is on a 150 carb, but on the Buddy 50’s carb, the bottom of the float hangs 5/8� below the flange when it’s held in the mounted position with that metal tab just touching the base of the float needle. This very important measurement doesn’t seem to be documented anywhere by Genuine - I got it myself from looking at a brand new carb.

You might have inadvertently disturbed this while you were cleaning your carb - I think this is what happened to mine.
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Post by atxg3 »

tenders wrote:My guess would be that the little metal tab that controls the relationship between the height of the float and the position of the float needle is set too LOW, ie, too far away from the base of the float needle - such that there is too much fuel in the float bowl.

I don’t know what the right level is on a 150 carb, but on the Buddy 50’s carb, the bottom of the float hangs 5/8� below the flange when it’s held in the mounted position with that metal tab just touching the base of the float needle. This very important measurement doesn’t seem to be documented anywhere by Genuine - I got it myself from looking at a brand new carb.

You might have inadvertently disturbed this while you were cleaning your carb - I think this is what happened to mine.
Well, your reply got me thinking, and I ripped open the carb again. I cleaned the needle jet port with some meguiars 201 Ultra Cutting compound. Did the whole cotton swab on a drill method, and really polished it up. Did a pretty good job.

At that point, I have been doing exactly what you described each time before, so instead I did the polar opposite of what my intuition told me, and raised the flange instead on the float. Now the needle would open sooner and close sooner.

When I was blowing into the fuel intake port and checking the mm distance, I noticed that my air would gradually increase in strength, rather than when I lowered the flange before, it would either not blow or 100% full blast blow.

I started the scooter and it did run much smoother than before. Albeit, it is not perfect whatsoever, and still runs a little rich, but light-years difference than earlier today.

That as well as when I reassembled the autochoke, I noticed that the gasket was pretty brittle and I replaced it.

So we're about 60% of the way there, but at least it starts and doesn't smell like a bonfire when I run it now.

Thanks for the idea! I'll keep you all posted with the progress tomorrow.
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tenders
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Post by tenders »

If she’s still running rich...raise that tab/flange a few more degrees and see what happens.

The float and needle valve operation are not always well-understood. The float level inside the carb changes very slowly, and as the engine draws more fuel out of the carb what really happens is that lower float allows fuel to dribble in around the needle valve at a slightly faster rate to maintain an equilibrium float/needle position. So, if the carb is clean, and the scooter and jets are stock, if she’s running rich either you’ve got too little air (you’re sure the air filter is clean, right? You didn’t mention it.) or too much fuel. It is entirely possible that the fuel level in the bowl is still too high and is drowning some of the holes in the jets which are supposed to be sucking air.

It is interesting that it seems to run better when the autochoke is activated. I’d think that its action, making the scooter run richer, would be counterproductive.
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Post by atxg3 »

tenders wrote:If she’s still running rich...raise that tab/flange a few more degrees and see what happens.

The float and needle valve operation are not always well-understood. The float level inside the carb changes very slowly, and as the engine draws more fuel out of the carb what really happens is that lower float allows fuel to dribble in around the needle valve at a slightly faster rate to maintain an equilibrium float/needle position. So, if the carb is clean, and the scooter and jets are stock, if she’s running rich either you’ve got too little air (you’re sure the air filter is clean, right? You didn’t mention it.) or too much fuel. It is entirely possible that the fuel level in the bowl is still too high and is drowning some of the holes in the jets which are supposed to be sucking air.

It is interesting that it seems to run better when the autochoke is activated. I’d think that its action, making the scooter run richer, would be counterproductive.
Oh no, the Air Filter is dirty AF. I'm waiting patiently until Saturday when my new one arrives. Thankfully I have a buddy... himself with a buddy.... and I borrowed his just to confirm. I didn't see much change at all with a clean air filter.

I will say that I am not also opposed to any vacuum leaks that are contributing as well to the running issue. But thankfully, at least the issue is slightly contained and hopefully the end is in sight.

When you mention the scooter running well when the autochoke is activated, I'm saying the ONLY time the scooter was not putting out clouds of dark smoke was ONLY within the first minute or so. After it was not cold and warming up, that's when all the issues would arise. I would hope that he gasket I added to the autochoke might have been good for it as well and contributed to the better running.

I do also have a new intake boot coming my way this weekend as well. Again after this scooter sitting for 4 years, I'm not going to be suprised if every rubber part needs to be replaced.
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Post by jrsjr »

atxg3 wrote:When you mention the scooter running well when the autochoke is activated, I'm saying the ONLY time the scooter was not putting out clouds of dark smoke was ONLY within the first minute or so. After it was not cold and warming up, that's when all the issues would arise. I would hope that he gasket I added to the autochoke might have been good for it as well and contributed to the better running.
:shock: I'm a word nerd so I'm going to make sure I understand in the simplest possible terms by taking out the double-negatives. You are saying the Scooter was putting out dark clouds of smoke after it warmed up?

Paging charlie55! Paging charlie55! The "autocock" is your bailiwick. What is going on here? Does this scooter just have a failed autocock? Thanks in advance for your expertise!
atxg3
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Post by atxg3 »

jrsjr wrote:
atxg3 wrote:When you mention the scooter running well when the autochoke is activated, I'm saying the ONLY time the scooter was not putting out clouds of dark smoke was ONLY within the first minute or so. After it was not cold and warming up, that's when all the issues would arise. I would hope that he gasket I added to the autochoke might have been good for it as well and contributed to the better running.
:shock: I'm a word nerd so I'm going to make sure I understand in the simplest possible terms by taking out the double-negatives. You are saying the Scooter was putting out dark clouds of smoke after it warmed up?

Paging charlie55! Paging charlie55! The "autocock" is your bailiwick. What is going on here? Does this scooter just have a failed autocock? Thanks in advance for your expertise!
Sorry for the double negatives.

Yes, the scooter ran great originally when it was cold. About a minute in, it would start to run rich and black smoke would appear slightly at idle, and when opening the throttle, I could basically recreate the movie 'Twister' from the black clouds it would produce.

The autocock measured well resistance wise. However, the gasket was completely destroyed when I removed it today to check it. I replaced the gasket with a makeshift one and seemed to help outside of the float level change.

I was not able to hook the autocock up in any way available to me currently to see visually if the needle fully extended and retracted just FYI.
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tenders
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Post by tenders »

I don’t understand the strategy of messing with the carb when the air filter is known to be clogged. It takes five minutes to rinse that out in a bucket of hot detergent, dry, oil, and reuse. Remove that variable from the equation.
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Post by atxg3 »

tenders wrote:I don’t understand the strategy of messing with the carb when the air filter is known to be clogged. It takes five minutes to rinse that out in a bucket of hot detergent, dry, oil, and reuse. Remove that variable from the equation.
Sorry if I did not make that clear. I already did that. Last night had a big tub of dawn dish detergent and cleaned the filter. Let it dry, tried it this morning. Same issue. Called my friend, asked them to bring over their buddy and newly changed filter, same thing.

I knew it wasn't only from a dirty air filter.
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Post by charlie55 »

From what I've read so far, I don't think that the "auto choke" is the culprit here. Even assuming that it was stuck in the "enrich" position, the amount of extra fuel added into the mix would not be enough to start producing clouds of smoke.
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Post by scootERIK »

If you have a friend with a Buddy 125 I would see if they would let you test their carburetor on your scooter. That might be the easiest way to figure out if it is the carb.

You could also test their auto choke in your scooter, or put your auto choke on their scooter.
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Post by jrsjr »

charlie55 wrote:From what I've read so far, I don't think that the "auto choke" is the culprit here. Even assuming that it was stuck in the "enrich" position, the amount of extra fuel added into the mix would not be enough to start producing clouds of smoke.
Broken Ring?
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jrsjr
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Post by jrsjr »

jrsjr wrote:Broken Ring?
Now that I think about it, broken rings would cause white/grey smoke. Durn...
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tenders
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Post by tenders »

Yeah, but so does a mis-set carb. When hearing hoofbeats think horses before zebras, Occam’s razor, etc.
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Post by atxg3 »

UPDATE

Okay all, thanks for all of the suggestions and tips here. I ended up calling a local scooter mechanic here in town and bought a used but very new-ish carb from a 2018 125cc for $20 - I couldn't say no.

Installed it and it runs like a dream, absolutely no issues.
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tenders
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Post by tenders »

Fantastic. Can’t beat a $20 fix. You don’t want to do this now, but the next time you have reason to take off the carb, compare it to the old one and figure out exactly what the problem was. My guess is the float level.
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Post by atxg3 »

tenders wrote:Fantastic. Can’t beat a $20 fix. You don’t want to do this now, but the next time you have reason to take off the carb, compare it to the old one and figure out exactly what the problem was. My guess is the float level.
Absolutely I will. If I find the culprit, I'll be happy to post here and update you all, thanks again for the help guys!
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Post by jrsjr »

atxg3 wrote:UPDATE

Okay all, thanks for all of the suggestions and tips here. I ended up calling a local scooter mechanic here in town and bought a used but very new-ish carb from a 2018 125cc for $20 - I couldn't say no.

Installed it and it runs like a dream, absolutely no issues.
That's great. Really glad to hear. I'd like to know what the real problem was with that carb, too. If you ever actually find out, please let us know.

Now the dangerous part begins. Riding on the Streets. :shock: Please be careful out there.
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Post by Dooglas »

hojoos wrote:did you overfill the tank?...autochoke on the carb working?...float have a hole in it?...needle valve spring installed incorrectly?
Did you read atxg3's posts? (if you did, I presume you'd already know the answer to all those questions)
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