Air box drains

[brando4905]

Hey Folks! I made an air box drain collector like the ones I've seen on this board out of pvc, barbed fittings, and a small breather. My problem is, after a 50 mile run the black gunk is now being pushed through the breather on top of the collector.

This is a used engine that was installed about 200 miles ago. Is this a result of the engine not being run enough yet? The breather I used is similar to what you would see on the valve covers of a race car.

[JackConrad]

Is the any kind of mesh in the breather to collect liquid and let "air" out? Maybe your check valves on then air box drain lines are stuck open?  Jack

[brando4905]

I'm not sure that I have check valves. Looks like there are just two brass elbows coming out of the air box connected to the drain lines. The breather is a small cone shape with steel mesh.

What kind of check valves do I need? Could I use something like a hydraulic brake booster check valve, like they have on hand in the auto parts store?

[luvrbus]

Send me your address and I'll give you 2 if I have 2 left you need the 900 rpm check valves they close at 900 rpm and open on idle the 1400 rpm check work the same   



good luck

[brando4905]

Clifford,

Thanks a bunch! I'll PM you my address.

Brandon

[bryanhes]

I had  detroit mechanic tell me you don't need them. Mine does not have any. Not had any problems. I also have built a drain box tank and put over 1200 miles since and have yet to have anything drain out.

FWIW,

Bryan

[edroelle]

With those breathers, I expect you are creating too much back pressure.  You want to have an open system (no resistance).   I have found that open mesh created too much back pressure on an 8V71.

Ed Roelle
Flint, MI

[luvrbus]

Bryan, you may not need the check valves but they were added to raise the air box pressure and every one knows a 2 stroke needs all the air it can get YMMD

good luck

[RTS/Daytona]

does this help

[Chopper Scott]

You sure get my curiosity up Cliff. At least I'm learning and try and pay attention. Are the check valves on the inside of the covers or are they outside? Mine just have copper tubes coming out of each side which I ran into catchcans. Thanks

[Just Dallas]

Removed

[Just Dallas]

Removed

[bryanhes]

So what are the ramifications of not having the check valves? Like I said I don't think mine has ever had them.

Bryan

[Just Dallas]

Removed

[robertglines1]

you will be surprised in the difference with  oil on toad and I can tell a difference in performance...the higher the air box pressure at running rpm the better the performance that is why some engines even use a turbo to feed the supercharger.ck valves let excess fluids out at low rpm then close to put all boost to engine when needed.