Unsolved oil leak mystery  By  bigmac (Read 1,281 times)

Be sure to check your vent hose off the vavle cover. Unhook it from the vavle cover blow and suck air through it, make sure it flows freely.

Without honing and putting in a good cross hatch pattern the rings will take longer to seat and possibly never will.

If the ridges at the top and bottom of the bore are not cleaned up you could also end up breaking both the top compression ring and bottom oil ring.

The only thing you got to guard yourself against during engine break-in is high RPMs.
Don't get your engine into high RPMs if you're doing the breakin.
Heavy load seems to be fine (fast acceleration), just no high top speed, or 8k RPM while accelerating from a dead stop. Yet another reason not to change rollers until the engine has at least 500km on it.

Here are Emission Systems you may find on a scoot some have all of them on some just a few of them.

Here is a EVAP system GAS TANK VENT CHARCOAL Canister:



Here is a EGR system Valve attaches to the PIPE by means of a welded piece of pipe:



Here is a PAIR system that all it does is suck in fresh air you will find a hose just hanging to get fresh air:



Then there could be a OIL catch Canister which would have a hose connected to the VALVE COVER PCV valve:
Alleyoop

Nothing was oily inside that round plastic part. A tiny amount of liquid came out when I first applied suction to that opening under the CVT cover but nothing else will come out now.

I noticed that unhooking all the vacuum lines kept the plug dry and the engine running better. So I hooked up one line at a time while giving the engine some time to run after each hook up. The plug stayed dry until the breather hose on the cylinder head cover was attached. This surprised me because I don't see oil coming out the cover's vent. Plus, any oil would need to go through an oil catch canister and air filter.

I hooked a clear hose to the cover's vent and put the other end into the air intake manifold. It ran terribly right as the engine started. I had to hold the throttle open some just to keep it from stalling.

This is the plug afterwords (camera focused on the background instead, but it's not too blurry to see):

It was wet and black in some areas.

Here's the spark plug hole:

The oil seems to leak out from around the plug. I don't know how since the plug is in there nice and snug.

The clear hose had moister in it, but it was clear like water.

I also found this oily stuff that's a solid shade of yellow weird:

That attaches to the oil catch canister.

My plan now is to inspect inside the cylinder head cover.

The cover and its baffles looked fine.

Even if I bypass all the vacuum lines it still idles poorly and always stalls if brought to an idle after revving.

While it was idling I took a totally transparent and clean hose and put it into to the air intake manifold. The engine stalled as soon as I put the other end of the hose against the vent opening on the cylinder head cover and I didn't see any moisture in the hose. It's like the gases that come out of the crankcase vent will stop the engine if they enter the air intake, even if for just a few seconds.

There also seems to be an excessive amount of water in the crankcase. If I leave a hose on the cover's vent for a few minutes, the hose becomes very wet inside and starts to drip out what appears to be water on its open end. Tried new gas but that didn't change a thing. Tried to look up information but every search result is about leaks in liquid cooled car engines.

Not sure where to go from here.