Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Iron Barrel => Topic started by: FiferWD on August 02, 2007, 02:55:32 pm

Title: Oil Loss
Post by: FiferWD on August 02, 2007, 02:55:32 pm
I have a continuing problem with disappearing oil at higher speeds (higher than 50mph).  I have the free flow exhaust and air cleaner on my 2005 ES with 18 tooth sprocket.  The slightest blockage in my breather tube will cause oil to squirt out of the timing case tube, on one occasion thick enough to cover the windshield of the car foolish enough to stay behind me in the right lane of Rte 301.

I have blocked off the tube from the timing chest, but oil still seems to disappear at the rate of about a pint in 20 to 30 miles when I am riding above 50 mph.  To paraphrase the old song, I just "Put a little oil in the old saddle bags and ride, ride, ride!" but I would like to find a better solution.  Has anyone tried the Bunn Breather on a Bullet?

Yrs,
Bill in Bethesda Maryland
Title: Re: Oil Loss
Post by: Brother Rhett on August 02, 2007, 03:27:14 pm
Hi Bill,

Welcome to the forum. I wish that I could help but (like so many questions) this one is a bit beyond me. I've forwarded your inquiry to our tech guys.
Title: Re: Oil Loss
Post by: HRAB on August 02, 2007, 03:44:36 pm
Some of the things that have been tried are fairly simple. The object is to keep a negative pressure in the engine. If it becomes pressurized, oil will pump up the timing chest tube. That tube is intended to return any oil from the catch can to the engine.

 The modification kits work. The modified breather tube for the timing side cover contains a check valve that will help prevent pumping of oil up the tube.

The simple things:
frequently check the breather tube from the top of the tank to the catch can. It can plug with a mix of oil and water vapor as a material that looks like mayonaise. One person claims that this tube can be re-routed to eliminate the sump in the middle of it by routing it over the frame member with success in reducing the build up. Check the duck bill inside the catch can to be sure the snap clip isn't holding it open. Ad an automotive PVC valve in this line to augment the duck bill.

Over filling the oil is another primary cause of the loss of oil. Check the level cold. It should be below the midpoint on the dip stick. Check the oil hot after the bike has been off for a few minutes to be sure it isn't over full when hot.

Title: Re: Oil Loss
Post by: FiferWD on August 04, 2007, 07:29:32 pm
Some of the things that have been tried are fairly simple. The object is to keep a negative pressure in the engine. If it becomes pressurized, oil will pump up the timing chest tube. That tube is intended to return any oil from the catch can to the engine.

At this point I have blocked the return tube and installed a brass drain cock in the catch can to facilitate draining the goo.  I cleaned off the engine and bike thoroughly, which enables me to get a better idea of where the oil is going.  So far, I have seen no evidence of it going through the catch can, nor do I see any signs of weeping.  I also replaced all the hose clips with real screw type hose clamps.  While it is no longer escaping through the breather network, oil is still disappearing.  With 10,000 miles on the odometer, I am beginning to wonder if my rings are letting oil be burnt.  After having adjusted the valve pushrods, I can stand on the starter without losing compression, though.  I replaced the plug last week and found that the old one was pretty crusted with carbon, but it had been in there for about 6,000 miles.  I haven't looked at the new one yet.
Title: Re: Oil Loss
Post by: dewjantim on August 05, 2007, 06:01:29 pm
Sounds like you need rings or valve guides. 10,000 is quite a few miles on these old 50's style motors. Most of the British engines from this era needed rebuilding (at least top end) at about 10,000 miles. Dew.
Title: Re: Oil Loss
Post by: gapl53 on August 06, 2007, 05:31:47 pm
I have a continuing problem with disappearing oil at higher speeds (higher than 50mph).  I have the free flow exhaust and air cleaner on my 2005 ES with 18 tooth sprocket.  The slightest blockage in my breather tube will cause oil to squirt out of the timing case tube, on one occasion thick enough to cover the windshield of the car foolish enough to stay behind me in the right lane of Rte 301.

I have blocked off the tube from the timing chest, but oil still seems to disappear at the rate of about a pint in 20 to 30 miles when I am riding above 50 mph.  To paraphrase the old song, I just "Put a little oil in the old saddle bags and ride, ride, ride!" but I would like to find a better solution.  Has anyone tried the Bunn Breather on a Bullet?

Yrs,
Bill in Bethesda Maryland

Blocking the tube from the timing chest will make matters worse because it is the return route for the oil that the positive pressure in the crankcase has pushed to the catch can under the seat. Make sure all the hoses are clear. You can blow them out with an air hose, and then check, the airbox and air filter for excessive oil contamination. You may need to replace the filter if it is oil soaked. Then follow HRAB's advice he hits it on the head.
Title: Re: Oil Loss
Post by: lunar on August 30, 2007, 08:03:46 pm
I have 350Machismo from 2000. I only have breather tube, without any duck bill or valve -
Lost it somewhere on the road... :-[ 

So, now I have straight rubber hose.

Can I improvise this or should I get new breather tube with valve of some kind?

Motor runs normally, does not spit oil (few drops).

Any advice?

Thank you in advance!
Title: Re: Oil Loss
Post by: little_a_o on August 31, 2007, 03:13:30 pm
I looked into my setup and I have an alluminum plug in my timing chest tube.  My breather tube goes to the can (air-filter housing). 

My question is, where would the timing tube connect to?

2006 Military

Little ao

Blocking the tube from the timing chest will make matters worse because it is the return route for the oil that the positive pressure in the crankcase has pushed to the catch can under the seat. Make sure all the hoses are clear. You can blow them out with an air hose, and then check, the airbox and air filter for excessive oil contamination. You may need to replace the filter if it is oil soaked. Then follow HRAB's advice he hits it on the head.

[old attachment deleted by admin]
Title: Re: Oil Loss
Post by: mbevo1 on August 31, 2007, 04:41:24 pm
Little ao - my '07 Bullet has three hoses attached to the catch-can.  One from the middle of the top of the crankcase, the other to the timing case on the right side of the motor. The third tube runs over to the airbox to vent gases back into the intake air.   I guess some of the previous versions only had the crankcase line and a drain valve in the bottom of the catch-can. The duckbill (primative but effective one-way valve to maintain slight negative crankcase pressure) is inside the catch-can connected to the crankcase line.

The timing case return line is designed to route condensed oil from the catch-can back to into  the motor.  The old RE design had an outflow tube from the crankcase (my motor has a stub at the base of the cylinder on the left side that was the original port) that terminated in a duckbill  over the chain.  Any oil (and other combustion by-products) blown out would be run down over the chain.  Automatic chain-oiler.  There was no return line to the timing chest in this configuration.  The catch-can and return line were added to eliminate the drips from the duckbill so we wouldn't pollute our pristine planet...  problem is, many of us don't want the glop going back into the oil supply, and the system can get gunked up fairly easily.  When the duckbill or return line get gunked up with condensed oil/water/etc. "mayo", negetive crackcase pressure can be lost and the bike will start blowing out a bunch of oil from wherever it can push it out.  If enough stuff gets blown into the catch-can, it will start pumping over to the airbox and will plug up the air filter.

I split the timing case hose and blocked the return line with a dowel.  Left the other end attached to the catch-can and blocked it with a dowel, too.  My configuraion keeps the catch-can and the vent to the airbox, but blocks the return line.  I have to drain and clean the catch-can regularly, but I had to do that anyway. 

Many bulleteers go back to the original configuration with the just crankcase line and duckbill and remove the catch-can completely.
Title: Re: Oil Loss
Post by: little_a_o on August 31, 2007, 07:21:11 pm
Mike and others;

Well I think my catch can has been retired from the bike by the previous owner being that I don't see one on the bike.  My crank case vent pic below shows the tube entering right into the air box to make its journey through the intake.  I pulled the box and removed the tube to test for blockage.  The valve seems to be allowing suction and a slight amount of oil can be seen at the carb's inlet. 

I'm still concerned since I am dealing with a messy oil  loss around the engine.
I'd like to unplug the timing case vent hose and see if that eases the oil leakage situation. 

Can they both be vented directly overboard  (environmentally aside)  or does it require a certain amount of restriction for proper operation? 

Thanks Little ao

[old attachment deleted by admin]
Title: Re: Oil Loss
Post by: deejay on August 31, 2007, 09:19:34 pm
Mike and others;

Well I think my catch can has been retired from the bike by the previous owner being that I don't see one on the bike.  My crank case vent pic below shows the tube entering right into the air box to make its journey through the intake.  I pulled the box and removed the tube to test for blockage.  The valve seems to be allowing suction and a slight amount of oil can be seen at the carb's inlet. 

I'm still concerned since I am dealing with a messy oil  loss around the engine.
I'd like to unplug the timing case vent hose and see if that eases the oil leakage situation. 

Can they both be vented directly overboard  (environmentally aside)  or does it require a certain amount of restriction for proper operation? 

Thanks Little ao

Since it looks like it's on your tappet cover i would check the head gasket, maybe re-torque the head.
Title: Re: Oil Loss
Post by: Kevin Mahoney on September 01, 2007, 08:59:30 am
We do offer a free replacement tube from the timing chest to the can for those of you who do not have the proper type. The correct type has a larger diameter for a cuople of inches after the tube leaves the timing chest. it has a one way valve built into it.
Title: Re: Oil Loss
Post by: little_a_o on September 02, 2007, 04:51:05 pm
Thanks,

I Re-torqued  the head and rode roughly 35 miles today.  Looks better.

Little AO

Since it looks like it's on your tappet cover i would check the head gasket, maybe re-torque the head.

[old attachment deleted by admin]
Title: Re: Oil Loss
Post by: little_a_o on September 29, 2007, 10:38:08 pm
Oil loss is still a problem and I have turned it over to the dealer to look it over.  Oil dissapears at a rate of about 1 pint per 80 miles when operated at a sustained 55 mph.

[old attachment deleted by admin]
Title: Re: Oil Loss
Post by: Foggy_Auggie on September 29, 2007, 11:26:05 pm
My same problem - one time oil blowout into the air cleaner - was caused by a thick white sludge blocking both hoses going into the under seat catch can.  This blockage created a pressure causing the smaller hose from the timing chest to blowback into the catch can - filling it and then overflowing into the short hose to the air cleaner box.

The fix was removing the seat.  Taking apart the catch can. Removing both large and small diameter hoses from the can and the engine.  Then pushing a rod through the hoses - rinsing kerosene through the hoses, then air blowing dry.

There was a thick white sludge in the center of both hoses.  Caused by moisture congealing with the oil residue.  I think this started on the freight ship across the Pacific in the shipping crate.  As this problem was early on within the first couple hundred miles of riding.

After the above procedure and changing the oil and filter at 300 miles this problem has never occurred again.  Although stop and go short trips and not getting up to sustained operating temperature may cause residue to return -  I don't do short hops.

Regards, Foggy
Title: Re: Oil Loss
Post by: mbevo1 on October 01, 2007, 01:34:45 pm
Here's a breather solution from Tim Busby, an RE expert from New Zealand (as posted in the Bullet-mania yahoo group...  I plan on doing this one today!

Mike and Stumpy in Michigan

"A Lot of owners of post '04 bikes (Bullets and Electra X) report engine
breather problems; to which end there are several highly (expensive)
touted fixes to 'cure' the 'problem'.
Not required!

The root of the problem is the main engine breather pipe that comes off
the top of the oil tank; it is routed underneath the main frame cross
tube, then it passes underneath the battery, and curves up into the
catch can.
That very first bend in the pipe is acute, (not a good start) and then
the pipe is forced to dip down under the frame tube and battery.
There in lies the problem; that low point dip in the breather pipe
fills with oil and condensate, eventually blocking up. Slowly it is
pumped up to the catch can, in time the catch can fills with the foul
stuff. Soon all the breather lines are blocked with the excrement, and
then the oil and condensate gloop is forced into the air filter
housing...
A double helping of crap on cold soggy toast for dinner...
:-(

The cure:
Disconnect the main breather pipe completely.
Remove the main breather pipe from off the top of engine, and disconect
it from the catch can.
Turn it around so that the acute bend is no longer attached to the top
of the oil tank. (That end is now going and onto the catch can)
Instead of the breather pipe passing UNDER the frame cross tube, run it
OVER the frame and behind the battery, and back up to the catch can.
Ensure that the pipe has a constant rise in it, No dips of falls.
it will be a 'tight' fit, but it does fit...

That is half the fix.
Now any oil that is carried out from the engine with the crankcase fume
and that passes into the breather pipe is able to drain back into the
oil tank. No longer does it condense in the breather pipe and cause it
to block.

The second part of the fix has two options; one is a factory retro
upgrade for the Drain pipe that runs from the catch can back to the
timing cover.
For the Electra X it involves the fitting of a short Duck Bill breather
INSIDE the timing cover, onto the internal end of the breather pipe.
On the Classis, the upgrade involves a replacement Drain pipe with an
internal Duck Bill installed. Though both are interchangable...
This stops the engine from venting UP the Drain pipe, but allows for
any Oil that makes its way into the catch can to drain back into the
timing cover.
In reality, with the repositioned main breather pipe as described
above, next to no all whatsoever ever makes into the catch can!

So I prefer to disconnect the catch-can drain line, and blank off the
drain pipe on the fitting at the rear of the timing cover.
I simply run the drain line down to the rear chain, with a duck bill
fitting on the end of it.
Any oil that does get it to the catch-can is used to lube the chain.
Any fume expelled from the motor is still able to be recycled via the
Air-box.

In the case of the Electra X: Also disconnect the vent line from the
catch can that runs to the Primary chain case, and simply run it down
over the rear of the bike behind the gear box.
Block off the connection at the catch-can to maintained a 'Closed
circuit'.

Instant solution to the engine breather problems!
No more condensate build up in the engine or breather lines, no water
retained in the oil tank; clear breather lines at all times, and no
compromise to pollution control.
Takes about 10-15 minutes to do, and minimal cost for a secondary Duck
Bill breather to go on the end of the relocated drain line.

The net result also features in a slight drop in average crankcase
operating pressure. Oil consumption will be minimalised, and the Gloop
that used to be accumulating in the oil is free to be expelled as the
gaseous vapour the system was originally designed to handle.

Well tested and proved to work 100%.

Tim
N.Z."