Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Iron Barrel => Topic started by: Spitting Bull on August 29, 2007, 12:10:02 pm

Title: Catch-Can removal - a question
Post by: Spitting Bull on August 29, 2007, 12:10:02 pm
A question for those who have removed the catch-can and extended the cranckcase breather so that it discharges somewhere at the back of the bike or on the chain.

This modification removes a component which is designed to cycle the oil back into the engine and replaces it with a sort of constant loss system.  Is there a steady, noticeable oil-loss which one has to keep an eye on?

Tom
Title: Re: Catch-Can removal - a question
Post by: Trapper on August 29, 2007, 12:55:15 pm
If it is the catch can you are talking about, no oil is recycled into your crankcase. Catch cans are designed to be drained periodically in "an environmentally acceptable" way. In any case, the oil does not go back into the crankcase. if you do not drain the catch can on a regular basis (especially when riding in cooler conditions) the paper element will foul with expelled motor oil and will eventually cause an over-rich condition; plug will foul at the least, the engine will choke out and die at the worst.

Bottom line? You will use no more oil with a catch can installed or not installed.

I originally put a petcock my catch can and made a delrin tool to reach in and drain the can as it is fairly difficult to remove the drain plug with out disassembling the battery box. Eventually, I removed the catch can altogether and went with the duck bill. A good modification to do - it keeps the air cleaner oil free.

I believe our hosts sell a conversion that does recover the oil and directs it into the crank case via a modification to the oil fill plug - I have not seen one in use, but the basic idea is sound.

Hope this helps.
Title: Re: Catch-Can removal - a question
Post by: Thumper on August 29, 2007, 03:44:42 pm
A question for those who have removed the catch-can and extended the cranckcase breather so that it discharges somewhere at the back of the bike or on the chain.

This modification removes a component which is designed to cycle the oil back into the engine and replaces it with a sort of constant loss system.  Is there a steady, noticeable oil-loss which one has to keep an eye on?

Tom

Tom,

The fluids that are blown up into the catch-can and subsequently drain back into the case are not in large volume. There is no noticeable oil loss.

I've documented the hoses and catch-can, and my own modification here:

http://members.verizon.net/allofusmorrows/PerfUpgrade.htm  (under the "Hoses" section).

Matt
Title: Re: Catch-Can removal - a question
Post by: Spitting Bull on August 29, 2007, 06:28:35 pm
Thanks, Matt - that's an excellent page you referred me to, by the way.

I've had problems now and then with oil blow-back into the right hand toolbox and have been thinking about modifying the system.  I have heard that oil loss through the modified system is small.  But an observation the other day has made me wonder.  After cleaning out the pipes (from the crankcase to the can and from the can to the timing-chest) I went for a ride of about 5 miles.  I happened to check the oil first.

When I got back I found that there was oil over my left boot and all over the flat part of the engine behind the cylinder.  The pipe had come adrift from the rear of the timing-chest.  (I probably pulled it off accidentally when fitting the other end back onto the catch-can.)

There was enough oil to drip off and cause a puddle when I put the bike onto the side-stand. I checked the oil again (bike upright, of course) and the level was noticeably lower than before.  It seems that there was  - or there should have been - oil or oil-vapour passing through that return pipe just about all the time. 

I'm still puzzling over this one - if I had had a one-way system in which the oil was only allowed out of the engine without being circulated back in,  I think I would have been losing oil all the time.

Tom
Title: Re: Catch-Can removal - a question
Post by: Trapper on August 29, 2007, 08:41:22 pm
When was the catch can to timing chest connection added to the Bullet?

My 2002ES does not have this connection. The oil blow-by pipe goes to the catch-can and from there to the air cleaner box. My previous comment will not make sense if your catch-can has a return to the timing chest. Sorry!
Title: Re: Catch-Can removal - a question
Post by: dewjantim on August 29, 2007, 09:28:53 pm
Thanks, Matt - that's an excellent page you referred me to, by the way.

I've had problems now and then with oil blow-back into the right hand toolbox and have been thinking about modifying the system.  I have heard that oil loss through the modified system is small.  But an observation the other day has made me wonder.  After cleaning out the pipes (from the crankcase to the can and from the can to the timing-chest) I went for a ride of about 5 miles.  I happened to check the oil first.

When I got back I found that there was oil over my left boot and all over the flat part of the engine behind the cylinder.  The pipe had come adrift from the rear of the timing-chest.  (I probably pulled it off accidentally when fitting the other end back onto the catch-can.)

There was enough oil to drip off and cause a puddle when I put the bike onto the side-stand. I checked the oil again (bike upright, of course) and the level was noticeably lower than before.  It seems that there was  - or there should have been - oil or oil-vapour passing through that return pipe just about all the time. 

I'm still puzzling over this one - if I had had a one-way system in which the oil was only allowed out of the engine without being circulated back in,  I think I would have been losing oil all the time.

Tom
Tom, it sounds like your engine might have wet sumped. Sometimes oil will seep into the bottom end if the engine is not run very often. I usually drain the crankcase if my bike has been parked for over a week or two. If I don't, it will spit oil all over the place and make a mess. I replaced my line with a duck bill breather tube. It does a fine job lubing the chain with the vapor that comes out of it. There is not enough oil to spray it all over the rear wheel which will happen from time to time when I lube chains myself. Its a good modification, cheap, and available from RE USA........Dew.
Title: Re: Catch-Can removal - a question
Post by: Spitting Bull on August 29, 2007, 11:48:07 pm
When was the catch can to timing chest connection added to the Bullet?

My 2002ES does not have this connection. The oil blow-by pipe goes to the catch-can and from there to the air cleaner box. My previous comment will not make sense if your catch-can has a return to the timing chest. Sorry!

trapper - I'm not exactly sure when the later version of the catch-can started to be fitted, but mine has it, and it's a 2004 model.

Tom
Title: Re: Catch-Can removal - a question
Post by: Spitting Bull on August 29, 2007, 11:53:08 pm
Tom, it sounds like your engine might have wet sumped.

Dew, that could be an explanation of why there was so much oil passing through the pipes in that short ride. It's quite possible that all the oil that came out did so in the first 30 seconds.  I hadn't considered that. The bike had been standing for about 48 hours.  I'm not sure if this is long enough to cause a problem, and the bike never smokes on startup, but it could explain things.  Thanks for that idea - well worth considering.

Tom
Title: Re: Catch-Can removal - a question
Post by: mbevo1 on August 30, 2007, 03:57:55 pm
Folks - I posted this reply to Jon about his over rich carb problem, but it really concerns the catch-can.   When the catch can system gets blocked, you can loose negative cranckcase pressure, and a fair quantity of oil can get blown out of the engine wherever it can... the systems is prone to getting plugged with white "mayo" especially when it's cold.  Here is my post on the other topic... I kept the catch-can but blocked off the return line.

My 2007 Classic had the same problems with "mayo" blocking off the crankcase outlet, catch can duckbill, and return line (it has a duckbill in it, too)... system is supposed to provide negative crankcase pressure through the duckbill in the can, vent the gasses over to the airbox, condense the oil and water vapor, and return the glop to the timing case.  When the outlet tube from the crankcase or the duckbill in the catch can get plugged up, the slight negative crankcase pressure provided by the duckbill isn't there, and oil vapor gets blown past the rings... the bike starts "using oil" and I usually have "mayo" on the dipstick as well.  if the return tube gets blocked (and there's a duckbill in that line, too)  the catch can doesn't drain properly, the duckbill gets plugged, and the effect is the same - oil blow-by.  Mine plugged up regularly early in the season when it was cold - takes time to get the oil up to temp, and the plumbing acts like a condensation tube... just have to take both tubes and the can off and clean everything out.

I don't like the idea of any of that junk going back into the crankcase, so I split the return tube and left about 2 inches attached to the return port on the timing case, then  blocked the tube with a dowel.  Left about 4 inches attached to the catch can, and blocked that with a dowel, too.  Now I can drain some of the stuff(mostly water)  in the catch can by removing the dowel plug in the line.  Catch can still gets glopped up eventually, so I pull it off and clean the can and the duckbill inside every 500 miles or so.

Mike and Stumpy in Michigan
Title: Re: Catch-Can removal - a question
Post by: LotusSevenMan on September 04, 2007, 09:14:08 am
New owner of a year 2003, 500ES Army Bullet here.
I see mention of the small plastic pipe that goes from the inlet manifold to somewhere. Mine is attached OK to the manifold (via a small bore metal pipe) and at the other end of the plastic it has an expanded section like it went onto a nipple or something but where is this something please?  ;)
Title: Re: Catch-Can removal - a question
Post by: hoppyre on September 04, 2007, 12:19:28 pm
New owner of a year 2003, 500ES Army Bullet here.
I see mention of the small plastic pipe that goes from the inlet manifold to somewhere. Mine is attached OK to the manifold (via a small bore metal pipe) and at the other end of the plastic it has an expanded section like it went onto a nipple or something but where is this something please?  ;)

On my 06 Bullet Sixty-5, the small plastic hose goes from the inlet to the PAV system in the left toolbox. (pulse air valve) But, I don't think the 03 models had this valve. Look at your airbox and see if there is a nipple for it to connect to.    Mark