crankcase vent mesh screen

[CincinnatiKid]

check these threads:

https://www.thegsresources.com/_for...23643-oil-in-airbox-after-80mph-for-150-miles
&
https://www.thegsresources.com/_for...9651-suddenly-lots-of-oil-blowing-out-of-tube


i have been experiencing the same issues, and have tried to fix it for a while. it seems from the first forum link above that there ought to be a mesh "chicken wire" type thing that sits above the valve cover inside the breather chamber where the hose attaches to. i dont have this wire mesh situation. i would love to find one and install it, because it worked for the people in the other forums. bwringer endorses it's use! what's not to love?

i can tell you that a few years back i tried to DIY the same sort of idea, and used a single ply of t-shirt material to screen the oil out and it worked extremely poorly!! lol

where can i find one of these?
i don't see it on the OEM fiches. i do have the wide gasket/blocker installed, as indicated in the fiche image...


this was last weekend, three separate times in one trip. yeesh... time for some new brake pads
https://youtu.be/13KEcpaHrIg

 

[unfocused]

Look at the 77-79 GS750. I actually have mine installed and then I've ran a hose from the V.C. to the battery box and secured a filter right above the chain/swingarm. Can share pics if needed. Might try 0/0 steel wool losely packed.

number 9

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[CincinnatiKid]

Some photos would be appreciated but not necessary, I’d just like to see what works for others. Mine initially came with a little K&N filter on the end of the hose but it only pitches downward from the V.C. So there’s no disincentive for the oil mist to drip down and out. In the past that filter got saturated and spread oil over the top of the swingarm.

I’ve seen some catch cans with inlet and outlet hoses on them, considered something like this but the online offerings are opaque and not really sized to be easily/cleanly removed if it was full.

https://www.amazon.com/muge-racing-Universal-Reservoir-Upgrade-Black/dp/B096TYHT2B

ideal would be prevention.

leery of stuffing steel wool up in the V.C., in case it drops some fibers or something into the oil bath…?

 

[Guest]

McMaster Carr sell various stainless mesh. I've used Scotch Brite Copper Coated Scouring Pads before in a pinch.

 

[Guest]

Here's a photo of one of my GSs. The catch can sits in the lowest part of the belly pan. The filter is much higher up. That tank holds about a pint. It has a valve that allows me to drain it easily. Vent tube routes up from the top of the motor.

 

[Guest]

My back halved GS. You can see the vent filter on the far lower left is again located higher than the catch can (center bottom). It's also far to the right of the tire. I designed the tanks with internal baffles the minimize the chance of oil getting to the filter. Also note the tank's easy access drain valve. A pop bottle with paper towel and a zip tie would work just as well and be lighter.
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[slayer61]

My back halved GS. You can see the vent filter on the far lower left is again located higher than the catch can (center bottom). It's also far to the right of the tire. I designed the tanks with internal baffles the minimize the chance of oil getting to the filter. Also note the tank's easy access drain valve. A pop bottle with paper towel and a zip tie would work just as well and be lighter.

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I have seen a beer can used more times than you can shake a stick at.

 

[CincinnatiKid]

I had a little inverted hand sanitizer bottle fixed to the end of the hose for a while, it worked great for normal commuting and track day use, and would allow me to flip but cap (facing down) to let the collected water and oil drain out, but the sustained fast riding overwhelms the capacity in short order, every time.

certianly there’s something to be said for a catch container more than 2.25 fl oz

pic of it chopped off during my last bout of frustration @ a gas station, thinking maybe it was causing a problem more than fixing it. Didn’t work.

thanks for the help, I’m gonna put some fine stainless mesh in the top cover and reinstall a bigger transparent catch container and see how it fares

 

[Guest]

It does look a bit small. I used a water bottle on my stock GS and it basically stayed dry but that bike has a mesh type baffle. The two shown also have similar mesh but these have a lot of blowby and I have to drain the tanks often.

 

[Grimly]

thanks for the help, I’m gonna put some fine stainless mesh in the top cover and reinstall a bigger transparent catch container and see how it fares

That's basically all the oem bit is, anyway. Enough volume to form an oil mist condensate trap.

 

[Guest]

I have a stock head like you show without the mesh. Note that the hose connects on the opposite end from the vent hole in the gasket. Also note the size of the cavity and drain ports. Even without the mesh like the later bike had, I wouldn't expect a lot of liquid to escape assuming there are no problems with the bike.

 

[chuck hahn]

Buy some stainless chore boy pot scrubbers and cut chunks to stuff the cavities. The mess vasically acts as a condensation surface rthat traps oil vapors and stops it short of the airbox

 

[eil]

Buy some aluminum screen, cut off a square a few inches wide, fold it up a bunch, done.

 

[CincinnatiKid]

Yes thanks all for the tips, I got some stainless screen material and will get it sorted and report back on how it works.

 

[salty_monk]

Yeah stock is just folded back on itself (like a squashed Z) three or four times

 

[93Bandit]

I don't mean to distract from the topic at hand, but if this mesh is missing can it cause excessive oil consumption? I've got a fair bit of oil in my airbox and I assume it's coming from the vent

 

[CincinnatiKid]

That is actually the basis of this conversation… welcome, read the above posts.

short answer, it certainly could be your reason, there’s one way to find out for sure… replace it!

 

[93Bandit]

That is actually the basis of this conversation… welcome, read the above posts.

short answer, it certainly could be your reason, there’s one way to find out for sure… replace it!

I read the thread, although I must admit I only skimmed it. However, it seems your main concern is oil draining out of the airbox, rather than oil consumption. Maybe they go hand in hand? I burned a half quart in 430 miles which seems excessive. I don't have any oil leaks and don't notice any blue smoke, so I'm not sure where it's going. I think the mesh is still in the cam cover but I don't remember for certain.

 

[CincinnatiKid]

I have no airbox , using pod filters. My breather hose terminates into a small catch container. That catch container was overflowing and dumping oil on my rear tire and brake.

If you’re missing a half quart into your airbox after 400 miles, I suspect you’d notice it leaking out of the airbox somewhere, maybe???

1) do a leakdown or at least a compression test to make sure your rings are sealing tight, rule out oil burning in the combustion chamber

2) maybe pull the breather from the airbox and route it into a makeshift catch can that you can inspect after 100 miles or so.

are you doing a lot of 80+ mph riding in those 400miles? My reading on this site is mostly people who are losing crankcase oil through the breather while doing extended high speed miles on the interstate.

 

[CincinnatiKid]

Got some mesh, and packed it above and below the gasket. Figured there’s no such thing as too much.