Carbeurator Leak and Carb Question

[Blahae]

Hello,
I have a 2007 R50X, and after sitting this winter, the carb seems to be leaking.  I see no drips for 24 hrs after driving it, but then I start to see slow drops of gasoline on the floor.  It is also acting flooded when I try to start it up after letting it sit for a day and it takes a lot of cranking to get it started.  I'm not an expert on carbs, so looking for a quick opinion on where the gas is coming from and what the potential issue is.  I'm hoping to remove the carb and clean it this weekend and I'm sure I'll learn a bunch by doing this.

My other question is about the brass colored port on the bottom of the carb in the attached picture.  It looks to be designed for a hose to be on it, but there is none.  Can anyone tell me what this port is for? 

Also, if the carb needs to be rebuilt, are there kits available for this?  I have a tough time finding R50X parts online, so any info on a good source woudl be appreciated.

Thanks for the help

[harry]

the brass pipe would be the drain hole for the fuel bowl....
 higher up on the carb body is a over flow hole .

sometimes these carbs get to much oil from a leaky oil check valve
and fill the carb with oil and cause the gas to overflow..

 no rebuild kits available ,
 the float or metering needle might be stuck

very important  do this first before removing anything from the carb!!!!
 there are 2 screws on the carb body one is idle and the other mix screw..
carefully screw them in and count the rotations to hit bottom and write them down
then when finished cleaning carb bottom screws and count turns out to reset.
there is a factory starting point but most likely its not the very best for where you live.
factory setting for most scooters -- idle 2.5 t out  main 1.5t out; but you have to retune
for best performance.

[Blahae]

Thanks for the help, I’ll give it a shot!

[Blahae]

Hi, I took the carb off, and in dumping the fuel out, I noticed it was tinted blue with oil. Does this signify a leaky check valve? If so, are these valves typically fixed by giving them a good cleaning? If not, I’m having a hard time finding a replacement check valve, so wondering if anyone is aware of a good source or an alternate product that would work well. Thanks again for the help!  Planning on cleaning the carb thoroughly tomorrow.

[harry]

yes thats what it is oil! and your right its a leaky valve!
so when the oil filled your carb it pushed out the gas causing your "leak"

you can clean them  but with use it can fix itself sometimes..
as for getting a new one  they're  very hard to find now

  if you do clean yours; spray some carb cleaner in a metal container and soak it in the cleaner
and  spray it in the hole . you should see spray come out from one side
 but when you spray in the other end it none should come out.

do not use a stick or wire  to poke at it.
you can use some low heat like put it next to a 100w light bulb
to warm it up before cleaning. LEDS don't have any heat  so use a
old school bulb.

[Blahae]

Once again thanks for the info. I cleaned the carb, and I soaked the valve in carb cleaner. I sprayed it in both ends, and I got flow in both directions. However, this should be the case right? The check valve is a low pressure cracking to let oil into the carb when the pump is working, but at low (gravity) pressure it stops flow. Due to the high pressure spray would it let flow go through either direction? Please correct me if I’m wrong with this. I know a check valve would typically limit flow to one direction, so either my logic here is correct or my check valve has failed. Thanks!

[Blahae]

Please disregard my previous question. I initially got flow both directions, but after soaking it a little longer I only got flow in one direction (going into the carb). This seems correct...must have been stuck open or something during initial cleaning. I think I’m all set at this point.

[harry]

there is a tiny ball bearing and spring inside the valve .
when oil is under pressure it pushes on the bearing and compress's the
spring .  sometimes the spring get weak and don't push the bearing back
to cut the oil flow.

use a good quality oil ,thin as versed to thick , and syn's are thinner than fossil
 i find Amsoil Interceptor is good syn's are better than fossil  on these oil systems.
you can stretch the spring a tiny bit  but don't loose the bearing or bung up the hose fittings!


oilyhans

[Blahae]

So I've let the R50X sit for about 36 hours, and this morning I noticed a drip on the floor again, and a blue-tinted drop of gas sitting on the carb.  Looks like my cleaning did not fix the issue.

That being said, what are the best options for this?  It's unfortunate that such a nice scooter with low miles and in great shape has such a simple issue, so I'm hoping there are some good options.

My thoughts are:
-Stretch the spring (how do I go about doing this?)

or

-Add an inline check valve to the hose (the new check valve will stop the head pressure of the tank forcing the small amount of oil between the new and original check valve into the carb.  Not sure what the pressure in the line typically is but the attached valve has a 1 PSI cracking pressure)

or

-Add a oil shutoff in the line (and hope no one ever forgets to open it up before riding it)


Do you have any further options or other ideas that you see in these scenarios?

Finding check valves seems to be tricky, but Grainger has one at the attached link that could work.  Any thoughts with this?

Thanks

[harry]

try soaking again ..

you have to wiggle and pull the brass fitting apart
with 2 tiny vice grips  to get to the spring .
don't bung up the hose attachments .

no idea if your grainger pressure valve  will work .

id forget the shut off idea. the motor will fry fast without any oil
you'd be better off to pre mix and just disconnect & plug carb oil feed.
you will still have oil being pumped to the bearings ... but too much oil
will also cause a lean condition so be careful with your mix.

oilyhans

[Blahae]

Thanks once again for the info.  I took the carb apart again and cleaned again, and now it runs well without leaks...multiple drives and multiple days of sitting and the carb is dry. 

One further question:  when I got the scooter, I wasn't sure if the gear oil had ever been changed.  The manual says to use 85W90 which was difficult to find...I had to buy it online and it was difficult even there to find it.  My question is:  in your experience, is the 85W90 necessary, or was that a typo in the manual?  Due to the horizontal fill port, I tried to measure out the 90CC and get it in the port but much of it leaked out making me play a guessing game with adding extra to compensate for what I lost.  I decided to drain the gear oil again and came up with a better filling method, but when I drained it (after a drive to warm it up), the fluid was inconsistent, with much of it having a typical oil look but the surface in the oil pail had a whitish, sparkling look to it.  When I looked at the oil it was actually sparkling.  Wondering if this is normal or if it was something like metal particles.  A photo is attached below.

Thank you

[harry]

yes its metal -- but that is normal for the first oil change
and that is why its done at 300 miles.

just use 90wt for the gear (hypoid) oil 

 rule of thumb for many scooters --
there is a overfill hole with a bolt in it .
or the fill hole acts as a over fill hole
ie; you have enough when it comes out the overflow hole.

 oilyhans

[Blahae]

Hi,
The scooter has 2500 miles on it, and the photo I showed was after I had already done one oil change (with 85W90) and driven it for 20 miles on the new oil.  I'm hoping the metal that you saw in the photo was just residue left over, or do you see this as a concern that something is going wrong in there seeing in that the metal particles were present after such a short distance with the new oil?

Thank you

[harry]

your scooter has unknown number of oil changes .
your second change might just be flushing excess oil
 that didn't drain the first time....

also you will see some metal on every change
just more and bigger pieces(flash)  at first 300 and less  when changed regular .
don't do it regularly and it will have more the next time its changed...

oilyhans