Crankcase Breather Hose Leaking Oil

[macmac]

Check that breather air........ it is air not exhaust. A breather allows air to go back and forth to the crankcase as the pistons move up and down.

On your old 1962 Ford Falcon that same breather hose came from the top of the valve cover made and 180 degree turn and ran down thew side of the in line by the fire wall and ended with a 60 degree chop cut with the long end of the chop to the front so a light vacuum was created, but it breathed air both ways.


If it really is exhaust gasses, you have a big problem with pistons or rings or something. That would be a hellova a lot of blow by.

Make sure the oil level is correct. With cold oil make sure it is just 1/2 way in the window. When oil is hot it expands and then maybe it will be in the top of the glass.

Next start the engine and let it idle. Remove the filter, and make sure it isn't clogged, but for now just let the engine run with the filter off and try to tell if it is exhaust or oily smelling air. Try to tell by placing a thumb quickly on and off the tubing if there is vacuum drawing air IN, and then pushing your thumb off, blowing air OUT.

How long have you owned the bike?

Does it PING all the time? if so and you find the air coming out is really exhaust the engine will need costly repairs.

I have another idea or 3, but i don't want to put out too much info at once and confuse things.

[macmac]

Oh yeah what kind of air cleaner kit is on the bike now? Another though on edit.

There is no 'U" shape now in the tube is there? Like the way a sink drain has a trap as a "U" shape in the drain???

There better not be,,,,,,,,

I think I want YOU to wipe off the end of that hose as clean as you can, and with a clean loose woven shop rag blow air by mouth into that hose with the engine OFF of course as well. It should be easy.

Sometimes I have problems with insects, like mud daubers wasps building nest in holes smaller than this tubing but at other times other critters move in.

The filter on a breather hose is there for that reason and pretty much only that reason.

[Patriot]

Oil level is good.Ran the bike in idle,put my thumb over the end of the tube.There seem to be more expelling of air than suction. The exhaust gasses are heavier both in color and smell. There isn't any pinging heard from the motor.I've owned the bike for 5 years and it has been a work in progress. The motor has been augmented.It has a Thunder Mfg's Hi-Performance kit,1.0mm-overbore pistons,10:1 compression ratio,re-jetted carburetor breathing through a re-jetted Thunder Air Kit,and a K&N Air Filter.There were a lot more but I've slowly replaced these with Kawasaki original parts.A year ago I also had a total top end re-build,the cam's were toast.the only thing I regret is not putting in sleeves and original pistons.Placement of the breather hose was done so it could breath not choke itself,in other words I made sure there was no restriction in the hose placement.The hose and filter (EMGO Crankcase Breather Assembly) I purchased new the end of last week.Before this the breather hose connected to the back of the carburetor breather box.I'm hoping I've given you all the answers you requested. I appreciate all your help Mac.

[Patriot]

Mac,the augmentations were done by the original owner,I am the 3rd owner. I have most of the information on all that has been done to this bike.Just last year I put a good 3,000 into it.I love this bike,it was the year I wanted.It just spoke to me from the minute I looked at it. I didn't want a Harley,I wanted a Vulcan.I wanted this one,just costing me a lot of money to make it right but I'm almost there.

[macmac]

I didn't want a harley either. I am a x foreign car tech. That hose needs to want air in as much as it wants air out. Be certain there is no obstruction.

That breather must breath in when pistons go up and out as they come down.

If you are sure is is exhaust there is big problems, as serious blow by. PING is detonation of fuel before spark which happens by lugging the engine a little in a overly lean condition and demanding power with the wrist.

But you have the fuel kit and in theory a matching air to fuel mix and NO Ping. The reason I am into this so hard is these bike come far to lean from the factory and PING hard which cuts the square piton tom and then cuts the comp rings, and gets you blow by, and blow by when it get bad enough can over pressure the crank case and blow oil out the breather tube.

On the other hand a breather tube that can not draw air in will blow out oil too........ I am more used to seeing this ion super charged engines that have a super charger problem and then all the oil in the crank case will be blown out any engine breathers and even out the oil filler cap.

The questions i have are IS the breather hose clogged with no filter? is anything in the fitting on the engine? Bugs?

What happens at idle with no hose on the breather fitting? Do it then breath air in and out about equal?

That crankcase has to breath in and out about equal.

It has been years but there was a liquid exhaust gas analyzer that fit radiator caps and used a blue fluid that turned green in the presence of exhaust gas. I have the tool still but no fluid. I can look and see that tool and get that info if you wish. It could be adapted to the oil filler cap with almost nothing. You would just run the engine with the tool in place where the oil filler cap is and the breather all installed.

If there is waste gasses in the crank case and over pressure this tool will tell it. The design was for waste gasses in coolant. Which proved a head gasket was gone on a car.

In this case it would prove if exhaust was in the crankcase and you really don't want that.

Where are you? That patriot thing makes me think of mass...........

[Patriot]

Nova Scotia Canada is my location. The exhaust is far out waying the suction. If there is a blockage,I would have to say it's within the crankcase itself. The bike does not Idle Like it did,nor does it start as easy. But it will run and idle after about 2 or3 tries,again this started with the oil issue. There isn't any pinging. What you said "On the other hand a breather tube that can not draw air in will blow out oil too" is what is happening. This I'm 99% sure it's doing.

[macmac]

Originally Posted by Patriot

Nova Scotia Canada is my location. The exhaust is far out waying the suction. If there is a blockage,I would have to say it's within the crankcase itself. The bike does not Idle Like it did,nor does it start as easy. But it will run and idle after about 2 or3 tries,again this started with the oil issue. There isn't any pinging. What you said "On the other hand a breather tube that can not draw air in will blow out oil too" is what is happening. This I'm 99% sure it's doing.

Pull the tubing off at the felt front as seated on the engine and run the engine at idle. Feel for in and out air there. No tube what so ever. Don't ride that way, as you could suck in sand.

Don't use that filter either unless you get it breathing clean and oil film is not good enough.

Check your filler cap O ring... make sure that O ring is in good shape. I am hoping it isn't, and so allows air in from there, then seals, and so when the pistons moved down over pressures the too small at this point real breather.

Do you KNOW it is exhaust? If you really know it is exhaust gasses the engine has a serious problem with combustion blow by, and in that case the engine will been to be opened up, may need new pistons and rings...

I hope not.

[Patriot]

I disconnected the hose from the filter and removed the oil filler cap.Cleaned the end of the hose and blew through it,I could feel air escaping from the oil filler opening.There isn't any issue with the hose. The O Ring on the filler cap is good,as I had just replaced it. When ever I have any kind of issue with the filler cap,it will leak oil.I feel the exhaust coming from the hose is related to oil.It doesn't smell like tail pipe exhaust,and doesn't look like tail pipe exhaust.
Even though I can blow through the breather hose,it pulls in very little air when running. I think that when it becomes unable to pull in sufficient air it dumps oil through the tube.
I've come to the conclusion,should the bike need a major motor job so be it.This is the only bike I've ever wanted.From the first time I sat on it,I knew I was in love.Riding down any highway,I'm in my zone. This bike will not become parts,it will be fixed.

[1500ccs]

It really sounds like your piston rings are shot. The exhaust smoke is one clear indicator that oil could be getting past the rings. If the rings are not sealing properly its possible some compression force is pushing past the rings into the case pushing oil out the vent. Couple things to check - compression test and spark plugs (are they wet?)

[Patriot]

Spark plugs are dry and good color. Unable to do a compression test,don't have the equipment. Unless I can narrow this down,I'm renting a trailer for the 2 1/2hour drive to see my mechanic.That's how far I have to go to see a good mechanic.But he's worth it,he is a Kawi man,he'll fix anything including Harleys. But if a Kawi comes in,it bumps the Harley.There isn't any thing about Kawi's he can't fix. But I'm still hopeful of a fix to save me the trip.

[cnc]

There is a automatic decompressor on these bikes so doing a meaningful compression test is tough, maybe a leak down test is better. It could be worn cylinders / rings, bad valve guide(s) or seals. It could also be as Mac was pointing out, some place the crank case is sucking air and pumping it out the breather. I had a bad crank seal on one of my tractors producing the same effect.
Also Mac to your knowledge does the breather on these motors have a disc valve or PVC valve. If there is maybe there is an issue there.

[macmac]

CNC neither. Just a tube.... when stock to very low on the backing rt side backing plate.

A comp test is pointless with RPM under 600 RPM which it is under the exhaust valves hang.

Comp on cly 1 will be around 150 psi and on cly 2 about 80 for what ever good that is on a new engine.

The TEST is a leak down test. In order to do that you need air, and you need to remove the left side as seated engine cover to turn the engine by hand counter clockwise from the stator bolt.

Using a pizza box to draw the shape of the cover place the bolts in the places they would be if the pizza box was the cover. These bolts vary upto 8mm's

Leave the tranny in neutral so you can warm the engine with the cover off. There is no oil or at least there should be no oil on the left side. If there is that is another problem.

With a warm engine set the ft cly to F in the window and with just one plug removed on cly 1 or front for F test it with the leak down tester. Record the reading. if it is good move on. if not and the meter shows loss find where.

To find where Lock the throttle wide open and listen to the throttle body hard up for hissing. Listen to the tail pipe for that cly hissing, and remove the oil filler cap and listen there, or in it;s pace to the breather hose install at the crank case.


Then move on to cly 2 'R' for rear.

Leak down testers should be in every techs took set, but are not. I have no idea why as I have one. They are not very expensive unless you don't already have air.

Now if you have a buzz bomb compressor that makes a lot of noise yyou need to pump it up and turn it off, before you use the air.

Mine has a 80 gallon tank.. and runs quiet.



CNC I am straining to think of a way like the filler cap O ring air could enter and then under crank case psi be trapped to all be forced out the breather tube.

Massive blow by is one way, a super charger failure is another where it's safety valve pops from a back fire and mis seats. Part of fire safety found on superchargers.

BUT Nomads don't have super chargers. If the oil cap O ring was bad and could allow air to be drawn in, but seal????????????

When pistons go up they create a vacuum in the crank case. When they come down they push air under them down into the crank case......

That air has to go somewhere. So a breather breaths air both ways.

This bike is going to see that Tech, and I for one want to know what he says.

No chance there is a engine oil leak on the left as seated running engine oil down over the side stand or puddling under the bike at night?????????
I have heard of oil leaks there from a pushed out clutch push rod seal, but in all cases so far that seal back out, not pushed in....

If some how that did get pushed in it might allow more air IN and seal back up when the pistons come down.

I hope someone local that can see has a good understanding of this as i really want to know.

Over head cam engines don't usually have any way of bad valve guides letting air into the crankcase but flat heads on tractors sure do. I think that one is out.. Worn clys sure thing bad rings sure thing, bad pistons rings and walls sure thing.

All pretty expensive....... i was hoping for a under 20 dollar fix

[Patriot]

I was hoping for a cheep/easy fix,I have to trailer the bike Friday morning to my mechanic.I have kept him informed as to the problem and what's been tried to fix it. I have settled on a few bucks to a couple of thousand.I want my bike fixed. If by chance it is the pistons/rings,then it will be new sleeves, pistons and rings. This will just about do it for getting rid of the aftermarket stuff. With the work I've had done in the past,it will be like a new bike.
I would like to thank all who have had input into my problem,and a big thanks to Mac. If you ever decide to take in the "Wharf Rat Rally" in Digby,Nova Scotia,Canada on Labor Day Weekend,Look me up. I live an hour from the Rally.

[macmac]

Make sure the plastic oil gear is gone.... and you have a steel gear. I am sorry to have run out of ideas. We are almost neighbors. I have family near Bar Harbor. Been to NS and Cape Breton and love the place. My grandparents came from there. Lyons and McKay. been to louisburg to fight You guys tawk like pirates! I may have been in that town to China Sea's Trading, or a name like that for a trading company that deals in nautical parts from older times.

I spent 6 years seeking real hemp rope, not long strand manila. I have a coil now of soft as cotton tan in color real hemp for bolt rope and running rigging, but it sure was hard to find. My other hobby is ancient ways and finding the real thing is very hard anymore.

6 years is a long goose chase. Took me to key West to Meat Cove and more.

Most people call long strand manila hemp now. I got a little rotten piece about 2 meters long off the Mayflower II and that was tarred.

I may have the very last long strand manila for the Royal British Navy in new old stock still in the wrapper (whats left of it) complete out of the weather real Stockholm tarred rope in Brit Std 5/8ths. real rope not line.
The hemp I have is 9mm line.

I am a strange guy huh?

[Patriot]

We all need and get our fix's in many ways.Not to worry about the gear,it had been changed long before I purchased the bike. I'll try to write down what the problem turns out to be,and post it here. It will give us some closure. Patriot