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Crankcase Breathers

RJMFXDC

Member
I am having a hard time with a concept that I have been reading about and would like some input. Is there something inadequate about the ventilation system in a big twin engine? Do you need to switch out the breathers to a separate catch can or filter option? Any input or direction to an existing thread would help. Thanks

RJM
 
You won't help the crankcase breathe any better, you just won't be venting into the intake. Many don't like the fine oil mist running back thru the intake to be burned up like the EPA does.
 
By routing the oily effluent into the intake. It causes some carbon build up from burning it. Do you NEED to do it, probably not. I did mine after re-doing my top end just to keep all the new components that I spent a small fortune on, clean and carbon free. Your ride you decide.
 
By routing the oily effluent into the intake. It causes some carbon build up from burning it. Do you NEED to do it, probably not. I did mine after re-doing my top end just to keep all the new components that I spent a small fortune on, clean and carbon free. Your ride you decide.

Thanks for the replies guys. What system is preferable, catch can or the mini filter systems or are there any other options? I did see a thread that showed severe build up after 9000 miles. Didn't like what I saw.

RJM
 
A catch can will be less messy than a filter, you can also keep an eye on how much top end blow by of oil you have:D
 
By routing the oily effluent into the intake. It causes some carbon build up from burning it. Do you NEED to do it, probably not. I did mine after re-doing my top end just to keep all the new components that I spent a small fortune on, clean and carbon free. Your ride you decide.

Bodeen, can you elaborate just a bit on what you did? I'm thinking about re-routing mine and venting it to the atmosphere.
 
Just FYI, I rerouted my breathers to atmosphere. I ran the lines between the cylinders, down the front of the eng. case,then back to the rear of the primary. I do not have a catch can or filter. I check the end of the hose periodically and have never found oil dripping. The end of the hose and frame rail ARE slightly oily though. Just for grins, I'm gonna make a mini catch can from an old 35mm film canister, so I can really tell how much blow by there is.
 
Just FYI, I rerouted my breathers to atmosphere. I ran the lines between the cylinders, down the front of the eng. case,then back to the rear of the primary. I do not have a catch can or filter. I check the end of the hose periodically and have never found oil dripping. The end of the hose and frame rail ARE slightly oily though. Just for grins, I'm gonna make a mini catch can from an old 35mm film canister, so I can really tell how much blow by there is.

Thanks Pete, that was my train of thought. I'm thinking of addIng a T behind the a/c base and running 1 hose down and under the engine. Maybe add a filter to catch any oil mist.
 
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