Overflow tube issue
 

Hey all, gonna be long winded but could use some opinions. I had to replace a cracked left side crank case cover awhile back. The seal I swapped over in the crank case cover was bad. So I was getting a ton of oil in my overflow tube and actually could see in the oil view window it was losing oil. Got a new seal, replaced it and voila, no more oil being lost thru the overflow. However I now get the overflow still filling up with gas smelling liquid after about 20 miles of riding. No oil being lost, the view port never shows oil going down. Not sure what has changed. I used to get a little bit of the gas smelling liquid but now it completely fills up very quickly. I talked to Gerry at CSC and we really cant figure it out. He said if seals were bad I'd be experiencing bad idle, missing etc. I experience none of that. The bike has been running totally fine, absolutely no issue whatsoever. Anyhoo, just looking for opinions. Other than being a pain in the ass to have to drain every 20 miles or so it doesn't seem to be affecting performance. Thanks for reading

Are you talking about fluid in the clear tube attached to the OSC ?

Yup, before the crankcase change I would get a small amount but now fills up after 20 miles or so.

No real idea on this and You've probably done this already, but I would -

1/
Get some fresh oil in the bike as your old oil could be heavily contaminated if the oil water separator has been clogged up with over flowing oil.

2/

Make sure the foam element in the oil water separator is clean and not blocked. Also all of the tubes up to the air box, ensuring a clear flow.

:shrug:

JKR, I'd like a bit more information. Where are you located? What are the local riding conditions (hot, wet, high altitude). Are you still in the break-in mode, ie. still staying below 5K rpm?

We, as a group, have discussed the OCS (that gadget between your crankcase and the air box, it's supposed to strip off moisture before the moisture gets to the airbox) and why one even needs it. You can give us another data point.

Peter Y.

I took the damn thing off and vent directly back into the airbox .... over 300 miles and no ill effects. Others, knowledgeable folks who post over at ADV, have done the same with a lot more miles than me. I dont know if anyone here has tried it.

EDIT.... Detours & jbfla.....I didn't know you two, or anyone else here, had gotten rid of it..didn't mean to not mention you guys...sorry. I know others here are working on the thermobob bypass but this method is simple old school and fits my needs nicely and famed cheap!

Thanks for all the replies. First, i have just over 6000 miles on the bike. Ride about 1000 miles per month. I was meticulous with the break in and am diligent with maintenance. I live in western Wa and yes, Ive seen the milky fluid every once in a while in the tube. This however looks like oil and smells like fuel. Like I mentioned i dont see any oil level issues after the new seal in the crankcase cover. I replaced the oil separator thinking having all that oil going thru it may have damaged it. I will tell you that when I removed the hose from the separator that goes to the air box about 2 ounces of the liquid poured out. Now I've checked the air filter and it is not saturated with fluid. Just feels oily from the filter oil i use and is definitely unobstructed. I still get fluid coming from the air box hose after a ride which concerns me a bit. Like I said, no idle issues, no missing, seems to run great. Im curious about the bypassing the filter all together but am concerned with the amount of fluid generating I'd mess up the air box. I've tried to look in the air box best I can and it doesn't seem like there is standing liquid in there but to be honest I cant tell for sure and don't know how to remove to check, at least not yet..

JKR, I was getting a lot of fluid in the OCS catchtube, but maybe a little less than you. Mine would fill up in about 40 miles with a yellow fluid that looked and smelled just like fuel. I even lit some in a can and it burned like gas.

I absolutely hate how fast it fills up, and I hate dumping fuel on the ground. But I worry that if I don't dump it, the fluid level could reach the OCS and block it, leaving contaminants in the oil.

So, following the lead of several others, I've been experimenting with a direct line from the crankcase to the airbox over the last several hundred miles. So far, I've experience no gain or loss in power and no change in engine performance (like you might experience from a gummed up throttle). And the airbox catchtube has been dry.

Given all this, one of two things is happening:

1. The fuel and water vapor from the crankcase is burning up in combustion instead of collecting in the OCS catchtube.
2. The vapors are condensing in the tube and dripping back into the crankcase, contaminating the oil.

Likely, a little of both is happening ... but how much?

To find out, I plan on doing a Blackstone oil analysis at my next oil change to find out what's going on. If I find a lot of fuel in the oil, I'll either go back to the stock OCS configuration, or maybe experiment with a higher temp thermostat to help vaporize more fuel and water.

But if the level is under 5% (which other RX3 owners using the stock OCS are seeing), I'll continue bypassing it.

Hi Detours,

I'm doing the same thing.

I'm running the engine for another 1,000 miles, then taking a sample for another analysis.

Joe B., Pete, and Peter Y don't think 4 to 5% of fuel in the oil is significant.

I would tend to agree with them if my oil analysis results were consistent.

But the amount of fuel in the oil has been increasing with each analysis.

http://i42.photobucket.com/albums/e3...pszp0hmauh.jpg

So far, after 350 miles, the hose is clear and the tube under the airbox is empty.

jb

jbfla, that's cool that you're using clear tubing out of the crankcase. Should make it easy to see any contaminants or fuel discoloration over time.

I've had mine plumbed up just like that for just about 1000 miles now and no issues. I like the clear tube idea! This is how every other motor cycle I've ever owned has done it.

i thought thr same make it easy on yourself:clap:

That's why I used the clear tube...to be able to see what's going on.

I was wondering if the original poster, JKR, has tried inverting the OCS.....I'm still not sure which way is up....:hmm:

Detours, congrats! You made it onto the CSC Blog.

You must be one of Joe B's "good buddies"..... :)

jb

Thx again guys. I talked to Gerry at CSC about the position of the OCS. Basically he says "cap" side up but in all honesty shouldn't make a difference. I've been paying more attention and the tube fills close to full after 40-50 miles. I'm toying around with the idea of doing the bypass thing but still have concerns about that much "contaminated" fluid making it to my air box or mucking up my oil in the engine or blowing nasties out the exhaust. I'm not sure if that's a valid concern or not as I am barely mechanical, have an idea, learn quick but you know...

The Bashan 200 and I are mentioned and pictured in that blog too :clap: