Gy6 150cc vacuum line blowing off?? By inkbytez (Read 4,592 times)

[inkbytez]

I have a 150cc GY6 4 stroke
The vacuum line from the valve cover to the transmission keeps blowing off from the transmission end and spraying oil all over the place?

no idea why it's doing this.

[Bashan]

Part of the problem is it's not a vacuum line. They don't blow off of things because of the vacuum. Plus vac lines don't contain oil. They provide vacuum for various things like fuel valves etc. If the hose is coming off of your valve cover it's your crankcase breather. Often, these hook onto the side air cleaner to pull vapors off of the crankcase. You could tie the breather hose off higher than the valve cover and stick an old fuel filter in to keep crud out and oil from making it's way out. You'll need to plug the hose into the air cleaner to prevent a vacuum imbalance going into the carb. How about some pictures, that would help.

[inkbytez]

its on a gio 4wheeler.
there was a hose that ran from the valve cover to the transmission.
if i cut the hose and put a oil filter on it from the crankcase cover like you said. can i do same with the hose coming out of transmission?

there was never a hose went to the air cleaner

[Alleyoop]

Jul 25, 2014 21:26:16 GMT -6 inkbytez said:

I have a 150cc GY6 4 stroke
The vacuum line from the valve cover to the transmission keeps blowing off from the transmission end and spraying oil all over the place?

no idea why it's doing this.

The problem is The Valve Cover Vent Hose SHOULD NOT BE CONNECTED TO THE TRANSMISSION. The Trans as well as the Motor has to Vent they BOTH build up pressure inside them. So take the Valve Cover Vent Hose from the Transmission off and
put a Fuel Filter on the End of it and zip tie it higher than the Valve cover (IT HAS TO VENT) otherwise it will blow oil out. The Transmission also should have a VENT HOSE on it to relieve the pressure inside the transmission.

I see some scoots where they come with the Valve cover Vent hose connected to the Transmission Vent Hose which is WRONG, separate them they both need to vent.
Alleyoop

[inkbytez]

ok, thank you very much, i will do that. very much appreciated.

[Bashan]

My CF Moto Peg had a weird config where the crankcase breather pulled through the air cleaner and the CVT cover and had a little tube hanging out the arse of the CVT cover (I know...very weird). Anyhow, just for giggles I'd plug the hose going into the CVT or air cleaner just to be sure you don't have a leak.

[Bashan]

I'm sorry my bad brain fart, it comes out of the air cleaner box and doesn't go through the CVT at all.

[Guitarman]

That's your EVAP drain line. It catches all the oil and gas that comes out and collects it. You need to empty it on occasion.

[inkbytez]

Ok i done what ya said and it ran not too bad. seems to like flooding itself and intermittent spark.
sometimes i have to chocke the carb manually for it to start. not sure what thats about but i'm sure there is another thread. i'm about ready to throw a 2stroke 250cc engine on this quad. Mind you, it is fun while it runs..lol

[Alleyoop]

Have you adjusted the carb and or adjusted the valves. If you have to choke it to get it to start that is a FUEL delivery problem. Also trying to start it with the AIR FILTER off not enough fuel and to much air. So first thing is attach the Air Filter onto the carb otherwise tuning the carb without the Air Filter on will be for not.
Alleyoop

[inkbytez]

I havn't adjusted valves no. I tried tuning the carb and looking up proper setting, but mainly been just trial and error
i'm not real savy with these

[Alleyoop]

Here you go follow this procedure to adjust the carbs mixture:
scooterdoc.proboards.com/thread/1499/4ts-carb-tuning