HarleyTechTalk

Technical Forums => Shovel Head => Topic started by: a_disalvo on June 14, 2019, 08:15:51 AM

Title: vent to exhaust
Post by: a_disalvo on June 14, 2019, 08:15:51 AM
Trying to route the crankcase vent on my stroker so it don't spew oil fumes to the brakes and/or back wheel. If I turn it, it looks like it would fit directly into the rear exhaust pipe, would have to drill a hole and install a barbed fitting. Anyone try this? Thanks, Frank
Title: Re: vent to exhaust
Post by: cbumdumb on June 14, 2019, 09:31:46 AM
We use to run breathers out to exhaust on our old street rods with headers but we had tubes welded at angles with check valve on them the tubes stuck into the collector at and angle to work like a siphon gun
Title: Re: vent to exhaust
Post by: Burnout on June 14, 2019, 09:37:17 AM
Problem is sourcing a check valve that will hold up and last.

This will not work with mufflers and drag pipes suck, so it's not really practical.

Just placing a fitting in the side of the pipe will not work either it needs to be a tube that is angled in the direction of flow.
That will be a restriction in a single pipe, on race motors it is done in the collector where there is less positive pressure.

The check valve will limit flow at low speeds this is not a good thing.

Not practical for street use.
Title: Re: vent to exhaust
Post by: JW113 on June 14, 2019, 10:39:25 AM
How much oil are we talking about? If just a light bit, run the hose to the air cleaner backing plate and let the motor eat it. If it's a lot, then you have bigger problems to deal with.

-JW
Title: Re: vent to exhaust
Post by: 76shuvlinoff on June 15, 2019, 04:41:40 AM
I run mine to a Hayden Crank Vent over the swingarm pivot and point it at the ground on the right side.  I seldom see more than a drop or three after a ride but probably not the best choice it there's a serious failure. I suppose a guy could run it back to the axle but the brake and tire would still get hit.   I had a much bigger problem when a shock blew out.
Title: Re: vent to exhaust
Post by: kd on June 15, 2019, 05:58:55 AM
You do not mention year so I'll assume it's chain drive.  Run the hose over to the left side and bring the tip down so it just enters the space at the transmission sprocket.  You want any drips (if there is any) to fall on the chain rollers and not past them.  On occasion a drip will fall and you now have an automatic chain oiler.

Edit for iPhone translating what they thought I wanted to say.   :banghead:
Title: Re: vent to exhaust
Post by: Hossamania on June 15, 2019, 07:55:55 AM
Quote from: kd on June 15, 2019, 05:58:55 AM
You doymention year so I'll assume it's Bain drive.  Run the hose over to the left side and bring the tip down so it just enters the space at the transmission sprocket.  You want any drips (if there is any) to fall on the chain rollers and not past them.  On occasion a drip will fall and you now have an automatic chain oiler.

I like that idea.
Title: Re: vent to exhaust
Post by: 76shuvlinoff on June 15, 2019, 10:40:03 AM
Quote from: Hossamania on June 15, 2019, 07:55:55 AM
Quote from: kd on June 15, 2019, 05:58:55 AM
You doymention year so I'll assume it's Bain drive.  Run the hose over to the left side and bring the tip down so it just enters the space at the transmission sprocket.  You want any drips (if there is any) to fall on the chain rollers and not past them.  On occasion a drip will fall and you now have an automatic chain oiler.

I like that idea.

So must've H-D, it's been a lot of years but that's how my 76 was when I bought it in 94, assumed that was "factory".  I went to WWWs and didn't like the booger sling.  Installed an O ring chain and moved the case vent away from it.