Oil mist blow-by from front of head.????
Thread Starter
|
Banned
Joined: Dec 2017
Posts: 12
Likes: 7
From: East Coast
Oil mist blow-by from front of head.????
2007 Dyna FXDB. 10.5 cr 107 in.
I am only about 100 miles into the break in on this build. It has the AN Big Sucker. No separate breathers or anything, just the bolts.
Noticing increasing oil misting on right side of engine.
The source is not the air cleaner. It�s coming from the front of the front head. The space below the front rocker where it meats the head. Where you can look in front from the front of the engine where the front header connects to exhaust port. It is wet there. Oil seems to be coming out from that space in front, from rocker breather area. Oil spray from front blows to front of throttle body by the cables, exhaust and some spray all the way back to the saddle bag.
So, is this normal and can be corrected by an external breather assembly with catch can? Or is it something else within the rocker or head that needs attention? I have no clue.
Thoughts?
I am only about 100 miles into the break in on this build. It has the AN Big Sucker. No separate breathers or anything, just the bolts.
Noticing increasing oil misting on right side of engine.
The source is not the air cleaner. It�s coming from the front of the front head. The space below the front rocker where it meats the head. Where you can look in front from the front of the engine where the front header connects to exhaust port. It is wet there. Oil seems to be coming out from that space in front, from rocker breather area. Oil spray from front blows to front of throttle body by the cables, exhaust and some spray all the way back to the saddle bag.
So, is this normal and can be corrected by an external breather assembly with catch can? Or is it something else within the rocker or head that needs attention? I have no clue.
Thoughts?
HDF Community Team
Joined: Jun 2006
Posts: 12,773
Likes: 2,603
From: san antonio
Not normal. A picture is worth 1000 words. You need to clean all to the oil up, fire up the bike to initiate the leak and post a couple of picture but it sounds like poor fitting gasket or loose fastener at the rocker box.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,859
Likes: 7,980
From: poway
Well, from what I can tell its coming from between the lower rocker and head.. If the gasket isn't in backwards then either gasket surface was damaged or the head / rocker base has a defect/crack.
Trending Topics
Cruiser
Joined: Dec 2017
Posts: 137
Likes: 24
From: NY
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider
Verdad Gallardo
When the gasket is installed incorrectly, it make a messy oil leak. It fits both ways - correct and incorrect.
Last edited by Ed Ramberger; Apr 23, 2018 at 06:44 PM.
Cruiser
Joined: Dec 2017
Posts: 137
Likes: 24
From: NY
Thanks for the advice and pointing me to the lower rocker gasket. Well, I removed the top rocker and lower support plate. All looks good. It’s oily but the gasket was definitely in correctly. The oil passage was not blocked.
Then, I examined the edges of the plate and mating surfaces of plate and head. No cracks. No visible defects. Smooth. The Cometic gasket appeared fine.
I cleaned up as much oil as I could.
So, now what. I guess I will replace the gasket anyway. But not sure why this happened. It may happen again even.
So what else can I check before buttoning it up?
Then, I examined the edges of the plate and mating surfaces of plate and head. No cracks. No visible defects. Smooth. The Cometic gasket appeared fine.
I cleaned up as much oil as I could.
So, now what. I guess I will replace the gasket anyway. But not sure why this happened. It may happen again even.
So what else can I check before buttoning it up?