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  #21  
Old 08-12-2018, 01:14 PM
CatmanDobbins CatmanDobbins is offline
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Here are some pics of the carb. The little tube poking out is where I'm plugging the fuel line into. (Second picture)

There's a little screw (first picture, right screw) that has a spring on it. Is that what the idler jet is? I screwed it all the way in and then 2.5 turns back and tried again and nothing changed.

The last two pictures are just either side of the carb.
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  #22  
Old 08-12-2018, 07:18 PM
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yes that's the fuel in indeed..
vm22 clone alright..

the third pic has me worried though!
the marks on the cap look like someone put a pipe wrench to it (uhoh!)
and that string is surely not a good throttle cable either...

Anyways.. the plunger (what the string is connected to on the inside)
has a specific direction, if you flipped it (back to front that is.. upside down is rather obvious)
it blocks the idle circuit internally.

So follow a few simple tests:
1) check if there's fuel in the bowl, the bowl should have a fuel outlet (with a valve right next to it, you can see it in pic 4 on the bottom of the bowl)
open the valve slowly and see if you have fuel dripping out of the bowl.
If so, proceed with the next step, else tap the bowl slightly with a screwdriver handle, the float needle might be stuck if tha fails you need to open the carb and fix the issue internally (remove the bowl that is)

2) if there's fuel in the bowl, test if the fuel gets sucked up into the main nozzle,
first check if the plunger is installed the right way around [and best install a proper throttle cable]
remove the carb from the engine and lift the plunger at least half way up..
cover the engine side with a fresh paper towel and blow steadily into the intake side..
if the tissue is now wet with fuel, just reinstall the carb,
if it's dry (or wet with spit *giggle*) no need to reinstall the carb it needs a nozzle clean,
or rather full maintenance... remove the bowl, then the main jet, clean the carb with carb cleaner or boil it in lemon juice (disassemble as much as you can before doing so)
then use pressurized air to blow through all channels of the carb before reassembly.

3) if you got here the carb will deliver fuel to the engine.

Since you're rather confident about your spark, give that just a single more test..
by installing a fresh out of the box spark plug.
if that doesn't do (but does with a squirt of starter fluid) it's certainly not the spark not even a weak one..

Last thing to check is compression really.. remove the spark plug again and get a modern day rubber cork from some wine bottle.. carve it to fit into the spark plug hole loosly (must NOT drop into the cylinder of course)
put it in and turn the engine over (starter should do) if the cork pops out happily jumping onto the garage floor, compression as well should be okay.
[you can also test with your finger instead of a cork, but on combustion stroke the engine will try to suck in your finger... that can be quite unpleasant at times]

Now.. fuel, compression, spark and with that all there is to making an engine pop.

if it still doesn't run,
chances are the carb is way too lean for your engine size
(say jetted and/or dimensioned for a 50cc engine)
in which case you will have to at least rejet the carb (or buy a bigger one)

'sid
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  #23  
Old 08-13-2018, 12:04 AM
CatmanDobbins CatmanDobbins is offline
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Quote:
Originally Posted by itsid View Post
yes that's the fuel in indeed..
vm22 clone alright..

the third pic has me worried though!
the marks on the cap look like someone put a pipe wrench to it (uhoh!)
and that string is surely not a good throttle cable either...

Anyways.. the plunger (what the string is connected to on the inside)
has a specific direction, if you flipped it (back to front that is.. upside down is rather obvious)
it blocks the idle circuit internally.

So follow a few simple tests:
1) check if there's fuel in the bowl, the bowl should have a fuel outlet (with a valve right next to it, you can see it in pic 4 on the bottom of the bowl)
open the valve slowly and see if you have fuel dripping out of the bowl.
If so, proceed with the next step, else tap the bowl slightly with a screwdriver handle, the float needle might be stuck if tha fails you need to open the carb and fix the issue internally (remove the bowl that is)

2) if there's fuel in the bowl, test if the fuel gets sucked up into the main nozzle,
first check if the plunger is installed the right way around [and best install a proper throttle cable]
remove the carb from the engine and lift the plunger at least half way up..
cover the engine side with a fresh paper towel and blow steadily into the intake side..
if the tissue is now wet with fuel, just reinstall the carb,
if it's dry (or wet with spit *giggle*) no need to reinstall the carb it needs a nozzle clean,
or rather full maintenance... remove the bowl, then the main jet, clean the carb with carb cleaner or boil it in lemon juice (disassemble as much as you can before doing so)
then use pressurized air to blow through all channels of the carb before reassembly.

3) if you got here the carb will deliver fuel to the engine.

Since you're rather confident about your spark, give that just a single more test..
by installing a fresh out of the box spark plug.
if that doesn't do (but does with a squirt of starter fluid) it's certainly not the spark not even a weak one..

Last thing to check is compression really.. remove the spark plug again and get a modern day rubber cork from some wine bottle.. carve it to fit into the spark plug hole loosly (must NOT drop into the cylinder of course)
put it in and turn the engine over (starter should do) if the cork pops out happily jumping onto the garage floor, compression as well should be okay.
[you can also test with your finger instead of a cork, but on combustion stroke the engine will try to suck in your finger... that can be quite unpleasant at times]

Now.. fuel, compression, spark and with that all there is to making an engine pop.

if it still doesn't run,
chances are the carb is way too lean for your engine size
(say jetted and/or dimensioned for a 50cc engine)
in which case you will have to at least rejet the carb (or buy a bigger one)

'sid

Haha the string was only a temporary solution. We installed a cable. Now I went through the the steps you said and I was unable to get the carb to spray fuel. We now need to clean it tomorrow and spray air through and all that but every store is closed now so we can't go buy carb cleaner.

But shouldn't this carb not be mucked up? I took it out of the box a couple weeks ago and the engine has not been run at all. Is it really a common problem with a new engine having a non working carburetor?

Also as far as the positioning of the plunger we think we got that right. If we flip it back to front it doesn't go down nearly all the way (in fact the throttle is fully open when we have it that way even without tugging on the cable). If we flip it back it goes down all the way and blocks nearly all of the opening in the carb going towards the engine. This is correct right?

Thanks again for all your help. I hope after good clean it'll work but I'm tentative to say so as I don't understand how it could be dirty if it's so new. It also looked really clean when we took it apart.


P.S. In regards to the pipe wrench on the carb cap. We took plyers to it because I read that if it isn't properly sealed then it won't get the right air fuel mix (which obviously isn't our problem I now see). It's just supposed to be hand tightened I assume.
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  #24  
Old 08-13-2018, 02:53 AM
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the cutout notch should be on the same side as the fuel inlet to clear the idle jet,
but yes, it should go [almsot] all the way in..

Sure a new carb should be clean.. BUT in order to install the throttle cable (and that string)
you must've opened up the carb and removed the plunger...
the plunger also holds the main jet needle as you will certainly know.
if for one reason or another some dirt got into the void and entered the main jet the needle will have pushed it into the main jet.

and voila: carb clean on a fresh carb necessary.

but since you have a fresh carb, you can try to skip some steps..
just remove the bowl and plunger and poke the pilot jet and the main jet with a thin wire
(or even better: monofilament fishing line)
from the bowl side carefully and see if the wire emerges from the top.
if it does, a quick shot of shop air and you should be good.

and yes.. hand tight is sufficient.. otherwise that cap would've had a hex head

'sid
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  #25  
Old 08-14-2018, 11:03 AM
CatmanDobbins CatmanDobbins is offline
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She runs! Thanks again for all the help itsid and texan. Couldn't have done it without you. The carb just needed to be cleaned with a wire and carb cleaner and now it runs. Only thing now is that it releases white smoke when it gets into higher rpms but I'm really happy now that it runs at all.
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  #26  
Old 08-15-2018, 05:22 AM
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oh great it runs..

now, run it for a little while @ mid rpms ONLY
(a fresh engine does like to be run in a bit.. so be gentle at first)

is it a puff of white smoke or a constantly generated cloud?

'sid
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  #27  
Old 08-15-2018, 06:43 PM
CatmanDobbins CatmanDobbins is offline
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Quote:
Originally Posted by itsid View Post
oh great it runs..

now, run it for a little while @ mid rpms ONLY
(a fresh engine does like to be run in a bit.. so be gentle at first)

is it a puff of white smoke or a constantly generated cloud?

'sid
It was a bit of a cloud but we just drained some oil and it works like a dream. If I get some time I'll update the first post on this thread with the correct wiring diagram and all that.

Thanks again!
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