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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
How so? Just curious. I like knowing stuff, and you're one of the smartest Harley guys I know of.
By drilling the drain holes larger, it'll allow the oil to drain quicker, and keep oil from gathering in that area.
Up to .140" is OK.
My ex-wife never accused me of being smart......she used other words.....lol...thanks for the kind words!
Scott
Found out I was wrong. Talked to a K&N tech. today and learned that this system does eliminate the external breathers because it has its own internal breather vents milled into the plate that does direct the mist back into the intake. They are very small and had to look very hard into the tubes where the breather bolts are and then found the small holes in the velocity stack and could run a small copper wire in from the intake and it came out by the breather bolt. All this time I thought I had eliminated the breathers until recently I pulled the filter to clean it and found a small amount of oily residue in the intake. That's when I began to question if the breathers were blocked off as I thought. Now I know I need to install a breather kit. I can build it myself easy enough by tapping in some brass fittings and attaching tubes
Now the only question is to run the drain tube to ground, to a small filter can or a catch can like the one Sparkalot used, from Kuryakin?
Found out I was wrong. Talked to a K&N tech. today and learned that this system does eliminate the external breathers because it has its own internal breather vents milled into the plate that does direct the mist back into the intake. They are very small and had to look very hard into the tubes where the breather bolts are and then found the small holes in the velocity stack and could run a small copper wire in from the intake and it came out by the breather bolt. All this time I thought I had eliminated the breathers until recently I pulled the filter to clean it and found a small amount of oily residue in the intake. That's when I began to question if the breathers were blocked off as I thought. Now I know I need to install a breather kit. I can build it myself easy enough by tapping in some brass fittings and attaching tubes
Now the only question is to run the drain tube to ground, to a small filter can or a catch can like the one Sparkalot used, from Kuryakin?
To the ground, a filter, or to a catch can is just personal preference. My goal was to stop recycling hot oily vapor into the intake. So I chose to use a catch can because it contains the residue and it is easy to clean ( unscrew the little canister and wash the foam filter every few weeks) Also, stainless braided hose and a dab of chrome of the canister lends was a chance to dress up a bit. I had to modify the K&N intake casting such that the vapors do not enter the intake stream, but are directed into the hose system and catch can
Intercepted vapor using banjo breather bolts. Sealed the air intake where vapor would normally enter the intake.Same basic idea for any breather installation.The factory air cleaner normally bolts directly to the breather port, and inhales the vapor through the bolts via little ducts or orifices in the bolt.
Cut off casting bolt shoulders, used elevator bolts, nylon sealing washers, rtv seal, and acorn nuts to seal the vapor intake passsages
The three 1/4" allen bolts in the throat area. The two larger center drilled breather bolts at the top serve mostly as a conduit or pathway for the vapor to get from the heads to the intake. These are eliminated and replaced with short banjo breather bolts that have hose connections. Another way is to continue using the two large breather bolts, but drill and tap them ( On the bench ) for a hose fitting. Same basic idea no matter what type of air cleaner is on the bike. I made up my own kit based on a DK kit but I bought 3 or 4 feet of 3/8 stainless fuel hose from a local hot rod shop so I could route the hoses exactly where I wanted to. Cutting the stainless hose has a technique let me know if more details wanted.
The three original factory pattern throat mount locations
Used in place of the two long breather bolts.
Last edited by sparkalot; Aug 18, 2018 at 10:11 AM.
Reason: picture missing
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I had to modify the K&N intake casting such that the vapors do not enter the intake stream, but are directed into the hose system and catch can
) for a hose fitting. Same basic idea no matter what type of air cleaner is on the bike. I made up my own kit based on a DK kit but I bought 3 or 4 feet of 3/8 stainless fuel hose from a local hot rod shop so I could route the hoses exactly where I wanted to. Cutting the stainless hose has a technique let me know if more details wanted.
