starting problems By chrispetty1 (Read 1,884 times)

[chrispetty1]

ok JR did a tune up on my 150 for 2 reasons 1 it was getting really hard to start 2 it was almost time for it any way cleaned the carb was going to change the diaphragm couldn't tell if the little tube that the spring sets in comes apart or do you just pull the old one off and slide a new one on so i just put it back together with the old one still on i think that the problem because i did all the rest checked for spark checked for compression checked gas flow to the engine was going to put on a new manifold on but the one on my scooter has 2 hoses coming off it and the one i just got only has a nipple for one so i didnt put it on does it matter or can i just tie the 2 hoses together into 1 .sorry if these are dumb questions but as Ive said before im a cook not a mechanic

[sprocket]

You need to set the valve gaps... many starting and stalling problems are caused by the valves being too tight... most often the exhaust valve.

Generally I set the intake to .004 inches and the exhaust to .005 inches...

[chrispetty1]

did that with the regular tune up every 1000 miles or as needed and have checked it twice now to make sure that was not the problem and its not they are still right on .004and .005

[sprocket]

Good one... you are a rare breed! 90% of scooter owners haven't a clue about valves...

I was a cook too.. then I became manager of a Hilton Hotel...still love the kitchen

anyhow

So, you have spark and compression and fuel to the carburator?

OK on the intake elbow.. if you have and elbow with two nipples you need to replace it with the same kind ...joining the vacuum lines and hooking to one simply doesn't work very well...

Pull off the hose on the carb that goes to the air filter...maybe the air filter is plugged?

If you have spark, compression, fuel and air the engine MUST run... so you are missing one of these

[chrispetty1]

will check the air filter in the morning the starting problem goes like this it acts like its getting no fuel at first then it starts and dies then it acts like its flooded let it set and it starts and runs fine and the rest of the day it would start fine looking on the other boards and from memory of other posts i was thinking valves once that was checked i thought of crack in the manifold so i ordered one the picture showed 2 nipples the one i got only has one so much for ebay so i won't join the lines that's one question down i also thought of a pin hole in the diaphragm but couldn't tell how to replace it and the old one looks kind of stretched and old its probably simple to replace i just don't know how and i don't want to break it

[alleyoop]

The diaphgram has nothing to do with starting. It comes into action when you open the throttle to let more air in so that the Air Pressure pushs up the Needle out of the MAIN JET.

For starting it is the PILOT JET and PASSAGE and the ENRICHER(CHOKE), If you have the Valves adjusted correctly, Compression and Spark. That leaves FUEL Delivery or you have a very bad Air Leak.

Now you could of put the Rubber DIAPHGRAM in wrong and it is not sealing that would cause an air leak. The Rubber Diaphgram fits into a grove all around the top of the carb as well it has a little lip sticking out that goes into its own slot.

The TWO NIPPLES that you said you had WHAT where Each connected to?

If you could take a picture of the Carb area and hoses we would be in a better position to maybe spot something wrong.
Alleyoop

[chrispetty1]

the nipple on the right goes to the carb the one on the left goes to a round box that also has a hose going to the valve cover wish i could take a picture but got no camera

[JR]

Good Morning Chris, just saw this thread and you are getting some great help and advice from Sprocket and Alley, hang in there with these two on the job you will resolve this!

Alley is right on on the diaphragm as it will not effect starting unless you have a air leak around it.

Replacing it is very simple the top cover plate has two screws and just comes right off and be careful as you have a long spring right under it then the diaphragm is exposed and just lifts out. Lot's of places to get one but I would check for all of the common problems first including a bad leaking hose.

JR

[chrispetty1]

found the tear in the diaphragm now how do i replace the rubber i ordered on they sent me the rubber part but i dont see how to take the old one off to put the new one on

[JR]

Let me see if I understand you right, ordered just the rubber diaphagm itself not the whole diaphragm with the slide and needle itself?

Can you send a link as to what you ordered so we can be sure?

JR

[chrispetty1]

ok i can try i ordered it from partsforscooters.com15 164-259 Carburetor Diaphragm for 150cc and 125cc 4-stroke GY6 engines. .partsforscooters.com/169-245-Rubber-Boot_2?sc=2&category=124359#" rel="nofollow" target="_blank">.partsforscooters.com/169-245-Rubber-Boot_2?sc=2&category=124359# thats what i ordered i ordered it when i first got my scooter a year and a half ago as i was buying replacement parts seals gaskets and things like that

[sprocket]

>>>to a round box that also has a hose going to the valve cover

Something is wrong with this statement...

One vacuum hose goes to the ACV on the carb this is on the CURB side

A second vacuum hose goes to a petcock (the center nipple) a round silver thing with 3 nipples or to a vacuum fuel pump also round...

BUT...nothing should be going from the round box to the valve cover. If that hose is from either the petcock or the fuel pump it goes to a brass nipple on the STREET side of the carburator, lower down.. the fuel inlet

No hose should be going to the valve cover...

There IS a hose on the valve cover...it is a vent hose and usually goes to the air box...

Need to see how all the hose are connected

[chrispetty1]

im trying to get a camera

[sprocket]

Here is a basic fuel and vacuum diagram

Attachments:

[alleyoop]

You beat it to it sprocket he did not mention anything about a VACUMM hose going to his PETCOCK or Fuel Pump whichever is on the scoot.

Also he just got the Diapghram rubber and not the entire Diaphgram Cylinder and Needle.
You should get something like this:
.motopartscenter.com/24mm-carburetor-repair-kits-for-gy6-125cc-atv-go-kart-scooter-p-331.html" rel="nofollow" target="_blank">.motopartscenter.com/24mm-carburetor-repair-kits-for-gy6-125cc-atv-go-kart-scooter-p-331.html
Alleyoop