Yamaha PW50

[my67xr]

the pin that holds the float to the little towers ?
i might have a spare ?

 

[my67xr]

if it is, you could temporarily use a pin from a pop rivet ?

 

[Blender]

if it is, you could temporarily use a pin from a pop rivet ?

I have done this, and it worked.

 

[ricky_191]

Hi guys. thanks for your help. Here is a photo of it. The little bit on top has broken off or is just missing.. I'm not sure what's missing tbh.

Pics.. It slips in that little grove in the float

That little pin out of it is spring loaded.. I have no idea :/

 

[my67xr]

this is what it looks like

Yamaha description/part number, Needle valve assembly, 3L5-14190-01, RRP $18.99
i will see if i have one here, you can have it

 

[ricky_191]

I think that's what it's meant to look like. Mine is a copy carbie though so I don't really know. The needle from the copy carbie has a spring in the little top bit because you can push it in and it springs back out. Maybe there isn't a missing bit. It doesn't look like it's broken off either.

I'm starting to think it's ok and that the fuel mix is off. I mixed it at 30 to 1 but it could even be more rich then that.. maybe 25 to 1 ?

Should I mix in some more fuel and try it ?

 

[ricky_191]

it's still not going. Could the oil in the cylinder cause it not to run ?

Whats the stock settings for this carbie so I can reset it ? I'm pretty sure it's got a big enough spark there. I can't really think of any thing else.

 

[my67xr]

just try starting it with a bit of throttle.

is there any fuel leaking out the overflow?

the mixture screw needs to be about 1.5 to 2 turns out

check that the throttle cable is sitting into the top cable guide fully too

 

[my67xr]

also did the new ignition have a wiring diagram with it ?
if you are getting spark then it sounds like a fuel/carby setting problem

 

[my67xr]

next time you have the carby off, check that both the pilot jet and main jets are both see through.
and the bottom of the threads where they screw into the carby base, that you can see the hole in the bottom of the threads are both open, and can see light into the carby bore

 

[ricky_191]

I think it's a mix of every thing. I mixed the fuel to what I think is close to 40 to 1 and still nothing. There isn't fuel out the over flow until I undo the screw. I drained it and it filled back up ok.

there is spark there but it looks like a brown spark :/ and you can see it but how big should it be ?

There is also only two wires for this rotor kit lol. It's hooked up ok.

would not having an air filter on it matter ? I just want it to start.

Should I spray something in the spark plug hole to see if it will get it started ?

any more ideas lol ? Thanks for your help

 

[my67xr]

yeah no air filter will make it a lean mix,
might be able to try the mixture screw at half a turn out?

brown spark sounds weird ?
i would have thought it'd give off a white spark, maybe white/blue

is the spark plug tip wet ?

and is the top of the hoop for the inner rotor at the top like this ?

 

[ricky_191]

Hi.Thanks for your help once again

I don't have an air filter yet as it's still coming in the mail. What did you mean my half a turn out. Half a turn from fully seated ?

I can't see good enough to see the spark :/ I really need to get my eye looked at so I will do that asap.

I pulled the plug out and it was black and had gritty powdery oil on it. And it wasn't wet. I took the head off and there was more black stuff inside and it kinda smudges like dryed up oil. I'm guessing its the burnt up oil from putting it together ?

Pics any way. I got no ideas any more.

After I cleaned some out it was still around the piston seen here. Also in this pic. The studs are smaller then the holes in the cylinder and the head and the studs can wiggle around :/ Is that normal ?

Bad photo of the spark plug but the same black stuff. I don't have my dslr charged so i'm using my old kodak.

Any help would be appreciated. I hope I can get it to work, fingers crossed.

 

[my67xr]

did you clean the new cylinder before you fitted it ?
like inside all the ports etc

the studs difference i'm not sure there,
is the new cylinder the same as the old cylinders' stud hole size ?



the pic of the head looks like there are signs of the head gasket leaking ?
how much compression does it have, more than before ?
directly down the middle of your pic, it looks like there's gray/black exhaust/carbon trails at the top and bottom ?

 

[ricky_191]

I wiped it out and then oiled it with 2 stroke oil so the piston could slide in. Didn't clean out the ports.

I'm not sure on the studs also. I will have to match up the old parts.

There is more compression then before I think. It's hard to tell how much there should be since i'm guessing the old set up was pretty messed up.

It could be the head gasket leaking. There was so paint on the face of it from factory so it's hard to tell if it's paint or a burn mark. I will clean it up and re fit it for testing..

How can you tell if fuel is getting into the cylinder ? I think it's at the right ratio now.. maybe just carbie settings.

I will find out more for you tomorrow thanks mate

 

[ricky_191]

Hi all. I had a look and the stock head fits on there with out much wiggle in the studs. Much less then the new head any way.

I put the old head on after cleaning out the cylinder and still nothing.. It only sounded like it was trying to start once out of about 200 kicks.

Could it be the reed valves ? Carbie float thing broken ? Fuel mix ? Not enough spark ? Just a crap re build kit ? Fuel not getting into the carbie or coming out of it or just a mix of all the above ? I'm starting to get over working on it. Any ideas would be amazing.

 

[my67xr]

you could try kicking it over at WOT, give it a few kicks,
then use no throttle and it should start

did you suss out if the spark is white/bright ?

 

[my67xr]

if it doesn't start/fire, then it could still be a carby issue
take the spark plug out and see if it is wet with fuel

 

[ricky_191]

Hi. I checked the spark, got a boot and it's sparking well I think and it's nice and blue. I took the carbie off again and it seems to be filling up ok.There was fuel in it, I clean it all out again and it seems super clean inside. I put it together, put some fuel down the spark plug hole and for a bit there is kinda sounded like it was going to start but really nothing to get excited about.

I'm thinking it could be the reeds ? That's the only thing I haven't looked at. I don't know any thing about them or what they should look like so any info or recommendations, help ect would be amazing as always. So keen to get it to run. Thanks

 

[my67xr]

ricky,
how did you go with the kill switch arcing out at the bars ?
and did you get a chance to check the reeds yet ?