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@jayn avatar
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05 Px150, 74 primavera 125, Honda super cub
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@jayn avatar
05 Px150, 74 primavera 125, Honda super cub
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Location: Ma
UTC quote
Like so many others my 05 px150 drips oil out the air mix screw. It builds up at back of carb box. Today is the day I try and solve this. I have replaced gaskets many times, torqued down carb (evenly) to no avail. Seems to be getting worse.
I'm wondering if the hole where the oil comes in on the carb box looks strange to anyone? It's not a nice round opening. Does anyone have a pic of what theirs looks like?
Forum member supplied image with no explanatory text
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@jayn avatar
UTC

Hooked
05 Px150, 74 primavera 125, Honda super cub
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Location: Ma
 
Hooked
@jayn avatar
05 Px150, 74 primavera 125, Honda super cub
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Location: Ma
UTC quote
I have also wet sanded carb flat. I'm tempered to dremmel the opening. A pic of someone's would be helpful to see if theirs is a different shape.
Forum member supplied image with no explanatory text
@christopher_55934 avatar
UTC

Ossessionato
2007 Stella 225
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Location: Rochester, Minnesota
 
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@christopher_55934 avatar
2007 Stella 225
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Location: Rochester, Minnesota
UTC quote
Are you sure it isn't from normal spray or blow back from running. I saw a video on YouTube in slow motion.


⚠️ Last edited by Christopher_55934 on UTC; edited 2 times
@xantufrog avatar
UTC

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1980 P200E - "Old Rusty", 1976 ET3 Primavera
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@xantufrog avatar
1980 P200E - "Old Rusty", 1976 ET3 Primavera
Joined: UTC
Posts: 8891
Location: Atlanta, GA
UTC quote
They all leak out the back by the mixture screw. They are filthy leaky machines. Unless there's more info I'm gonna guess there's nothing wrong with the oil channel itself in the carb box
⚠️ Last edited by xantufrog on UTC; edited 1 time
UTC

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1958 Allstate 177VMC, 1962 Allstate, Yamaha Vino 70cc
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Ossessionato
1958 Allstate 177VMC, 1962 Allstate, Yamaha Vino 70cc
Joined: UTC
Posts: 2377
Location: Philadelphia
UTC quote
xantufrog wrote:
They all leak out the mixture screw. They are filthy leaky machines. Unless there's more info I'm gonna guess there's nothing wrong with the oil channel in the carb box
Why would it only leak oil though and not a mix of it was blowback?

I'm in the same boat. Every screw in the carb and box is tight yet still dripping oil. And if I leave the bike on the side stand it drips even more and hits the tire and brake drum backing plate.
@xantufrog avatar
UTC

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1980 P200E - "Old Rusty", 1976 ET3 Primavera
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@xantufrog avatar
1980 P200E - "Old Rusty", 1976 ET3 Primavera
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UTC quote
FridayMatinee wrote:
Why would it only leak oil though and not a mix of it was blowback?

I'm in the same boat. Every screw in the carb and box is tight yet still dripping oil. And if I leave the bike on the side stand it drips even more and hits the tire and brake drum backing plate.
I guess I assumed they meant "an oily mix" and not pure 2T. Are you sure yours is pure 2T? I don't see how pure 2T can make the journey from the tank far below uphill into the carb box and out the back just because the scoot is tipped a little on the kickstand. I think you're just experiencing whatever is in the carb still when you turn it off running out when tipped
@vespistaforever avatar
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1952 faro basso,P200E, Allstate, ET3, V98, Vespa Bacchetta, 1954 Allstate
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1952 faro basso,P200E, Allstate, ET3, V98, Vespa Bacchetta, 1954 Allstate
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UTC quote
JayN wrote:
Like so many others my 05 px150 drips oil out the air mix screw. It builds up at back of carb box. Today is the day I try and solve this. I have replaced gaskets many times, torqued down carb (evenly) to no avail. Seems to be getting worse.
I'm wondering if the hole where the oil comes in on the carb box looks strange to anyone? It's not a nice round opening. Does anyone have a pic of what theirs looks like?
this look normal,
Do you have a picture of the other side? (back of the air box?
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1958 Allstate 177VMC, 1962 Allstate, Yamaha Vino 70cc
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1958 Allstate 177VMC, 1962 Allstate, Yamaha Vino 70cc
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UTC quote
xantufrog wrote:
I guess I assumed they meant "an oily mix" and not pure 2T. Are you sure yours is pure 2T? I don't see how pure 2T can make the journey from the tank far below uphill into the carb box and out the back just because the scoot is tipped a little on the kickstand. I think you're just experiencing whatever is in the carb still when you turn it off running out when tipped
Positive it's just oil. Not a hint of gas to be found. Tonight I wiped the case clean and stuffed paper towels behind the air mix part of the box to see if that's where it's coming from or not. Does it on the center stand as well I forgot to mention.
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Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
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Molto Verboso
@scooterist avatar
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
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UTC quote
My PX150 does the same thing, it is oil mixed fuel that splashes back and up through the carburator Venturi then hits the air filter, soaks the oil from condensation and it has no where to go but to drip to the sides then down and when it fills up enough the carburator box there is only one way to drip again which is the hole on the air mixture.

Don't worry too much it is normal, it will happen over and over and opver no matter how many times you clean it.
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@jayn avatar
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05 Px150, 74 primavera 125, Honda super cub
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@jayn avatar
05 Px150, 74 primavera 125, Honda super cub
Joined: UTC
Posts: 171
Location: Ma
UTC quote
I too believe it is just 2t oil. I'm no stranger to spit back (from my other scoots).
Since this opening (see circled part in pic) isn't oval'd properly- is it impeding the flow of oil into crank?
Forum member supplied image with no explanatory text
@vespistaforever avatar
UTC

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1952 faro basso,P200E, Allstate, ET3, V98, Vespa Bacchetta, 1954 Allstate
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1952 faro basso,P200E, Allstate, ET3, V98, Vespa Bacchetta, 1954 Allstate
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UTC quote
JayN wrote:
I too believe it is just 2t oil. I'm no stranger to spit back (from my other scoots).
Since this opening (see circled part in pic) isn't oval'd properly- is it impeding the flow of oil into crank?
no is not
@christopher_55934 avatar
UTC

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2007 Stella 225
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@christopher_55934 avatar
2007 Stella 225
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Location: Rochester, Minnesota
UTC quote
JayN wrote:
I too believe it is just 2t oil. I'm no stranger to spit back (from my other scoots).
Since this opening (see circled part in pic) isn't oval'd properly- is it impeding the flow of oil into crank?
I don't think so, it's so little flow and pressure it's really just a dribble. On that note, no reason you can't clean it up if you want to. Sometimes I'm a bit OCD about something and it just makes me feel better.
@xantufrog avatar
UTC

Moderibbit
1980 P200E - "Old Rusty", 1976 ET3 Primavera
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Location: Atlanta, GA
 
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@xantufrog avatar
1980 P200E - "Old Rusty", 1976 ET3 Primavera
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Location: Atlanta, GA
UTC quote
I think it's oil-gas mix. Remember that gasoline evaporates. So the gloop you collect coming out of the carb screw and air filter will be thicker unless you're blasting a ton of gas back and looking immediately at a runoff. Also, that channel looks fine - it delivers oil at a very slow low-pressure flow into the carb to mix with the fuel-air mist just above the throttle slide, so you do want to make sure your carb gasket has the hole and that it aligns with this one in question to avoid impeding flow though
@chandlerman avatar
UTC

Innovator
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 66 Lammy S3
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76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 66 Lammy S3
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89 Days Since Last Explosion
UTC quote
Christopher_55934 wrote:
I don't think so, it's so little flow and pressure it's really just a dribble. On that note, no reason you can't clean it up if you want to. Sometimes I'm a bit OCD about something and it just makes me feel better.
I'd leave it be because if you clean it up, you're risking swarf getting into things and then you really will have a problem.
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@jayn avatar
UTC

Hooked
05 Px150, 74 primavera 125, Honda super cub
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Posts: 171
Location: Ma
 
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@jayn avatar
05 Px150, 74 primavera 125, Honda super cub
Joined: UTC
Posts: 171
Location: Ma
UTC quote
If it is just spit back wouldn't every P or Stella (or any SI top mounted carb) have this issue?
@xantufrog avatar
UTC

Moderibbit
1980 P200E - "Old Rusty", 1976 ET3 Primavera
Joined: UTC
Posts: 8891
Location: Atlanta, GA
 
Moderibbit
@xantufrog avatar
1980 P200E - "Old Rusty", 1976 ET3 Primavera
Joined: UTC
Posts: 8891
Location: Atlanta, GA
UTC quote
JayN wrote:
If it is just spit back wouldn't every P or Stella (or any SI top mounted carb) have this issue?
Maybe you should post a pic of the problem so we can see if this looks abnormal in some way?
@vespistaforever avatar
UTC

Enthusiast
1952 faro basso,P200E, Allstate, ET3, V98, Vespa Bacchetta, 1954 Allstate
Joined: UTC
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Enthusiast
@vespistaforever avatar
1952 faro basso,P200E, Allstate, ET3, V98, Vespa Bacchetta, 1954 Allstate
Joined: UTC
Posts: 66
Location: Garland tx
UTC quote
JayN wrote:
If it is just spit back wouldn't every P or Stella (or any SI top mounted carb) have this issue?
Looks like it's more an oil leak than a spit back but it could be also a spit back if your main jet is too big. What type of oil are you using for the mixer ?

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