EVO All Evo Model Discussion

Valve Stem oil seal leak.

Thread Tools
 
Search this Thread
 
Old Apr 3, 2011 | 11:51 AM
  #1  
tc's Avatar
tc
Thread Starter
|
Cruiser
Joined: Feb 2007
Posts: 138
Likes: 5
From: Dublin, Ireland.
Question Valve Stem oil seal leak.

Hi,
As some will know I did a recent top end re-build to cure a leaking base gasket and also fitted an EV27 cam.
All went ok and am delighted with result, but I noticed that while bike is idling on tickover it is smoking on both cylinders.
I recently removed the air filter and opened throttle fully and when I looked through carb, (S&S Super E) noticed that there was some oil in the in-take manifold.
I presume that the only way that the oil can get there is down the valve guides, hence I assume the valve stem oil seals are giving problems.
Unfortunately, this was the only part of the job that I did not do myself as I did not have a valve spring compressor and left seals with machine shop to fit after he re-seated valves.
My question is, can I just do a head job, ie, remove heads and fit new valve seals WITHOUT removing cylinders and fitting new base gaskets, will the ones there now be ok?
Thanks,

Tony.
 
Reply
Old Apr 3, 2011 | 12:18 PM
  #2  
miacycles's Avatar
miacycles
Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
Default

Let's see the original engine had enough miles on it to do the top end, and a machine shop did the valves. Did they replace any valves or guides??? If they were worn and not replaced that could give you problems. Valve stems can wear and have varnish build-up. Both of these can cause seals to fail. If the seals were instaled without using the protective sleeve can cause seals to leak. If the heads aren't draining oil properly that can cause problems.
These are just a few of the problems that can cause the symptoms you have. Hope this helps.
 
Reply
Old Apr 3, 2011 | 12:54 PM
  #3  
V-Twins & Bowties's Avatar
V-Twins & Bowties
Road Warrior
Joined: Dec 2010
Posts: 1,268
Likes: 507
From: Florida
Default

There is no way your going to look into the throat of a carburator and see valve guide seals leaking. Unless someone has Superman X-Ray vision.

More than likely your seeing oil from the crankcase breather/s accumulating in the manifold.
 
Reply
Old Apr 3, 2011 | 03:04 PM
  #4  
Spanners39's Avatar
Spanners39
Seasoned HDF Member
15 Year Member
Photogenic
Liked
Loved
Joined: Dec 2010
Posts: 7,736
Likes: 1,524
From: Coromandel Peninsula New Zealand
Default

Did you time the breather correctly when you fitted the cam?
 
Reply
Old Apr 5, 2011 | 07:13 AM
  #5  
M&D88FXSTC's Avatar
M&D88FXSTC
Intermediate
Joined: Apr 2010
Posts: 47
Likes: 0
From: Central Ohio
Default

my GUESS would be the new higher lift cam is causing the valves to travel beyond the worn spot where the seal previously ummm sealed lol. if that makes any sense

id think a reputable machine shop would've suggested new valves if they were that worn... but thats me thinkin out loud...
...

it may wear itself in, may get worse, Id just ride it a while n see unless its a smoke screen behind you.
just my
 

Last edited by M&D88FXSTC; Apr 5, 2011 at 07:18 AM.
Reply
Old Apr 5, 2011 | 04:49 PM
  #6  
tc's Avatar
tc
Thread Starter
|
Cruiser
Joined: Feb 2007
Posts: 138
Likes: 5
From: Dublin, Ireland.
Default New problem

Thanks for replies.
V-Twins and Bowties, I think you have it wrong. Engine is not running when I look through carb. For want of a better description, there is a "puddle" of oil in the manifold after running motor.
I am inclined to do as the the last post suggests, ie, ride bike for awhile. There is no smoke screen as it only smokes while idleing.
Another problem has reared its head. I seem to have a regulator problem now as after running bike for about 80 miles and stopping for coffee, it would not start and we had to jump start it.
After another 20 miles or so it started far*ting and missing like mad, so I turned ign switch to lights off position and it ran fine till I got home.
Charged battery overnight and disconnected it and left sand for 2 days without a drop in voltage and bike turned over ok, so it appears battery is all right.
While running, voltage across battery is only 12.6v and I believe it should be between 13.8 and 15volts for my bike. (1986 FLSTC).
Do you think my reasoning is correct?
I hope this is not a sign of things to come.....................
Thanks,
Tony.
 
Reply
Old Apr 5, 2011 | 06:34 PM
  #7  
Jim Kraft's Avatar
Jim Kraft
Stellar HDF Member
15 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: May 2009
Posts: 2,856
Likes: 127
From: Middle of Kansas
Default

Sounds like the regulator, but could be the alternator also. You can check your A/C ouput at the alternator plug. If it is OK it is probably the regulator. Mine went belly up last year, and you really don't know when it quits without an idiot light. Even my old 84 Iron Head Sportster had a charge light on the generator.
 
Reply
Old Apr 5, 2011 | 07:16 PM
  #8  
the blob's Avatar
the blob
Road Warrior
Joined: Sep 2006
Posts: 1,570
Likes: 45
Default

i know when our 05 twincam started having valve seal probs. it showd oil all over the threads of the plugs.
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Times Harley-Davidson Chucked Tradition Out the Window

 Verdad Gallardo
story-1

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-2

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-4

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-5

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-6

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-7

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-8

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-9

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
Old Apr 5, 2011 | 07:24 PM
  #9  
Jim Kraft's Avatar
Jim Kraft
Stellar HDF Member
15 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: May 2009
Posts: 2,856
Likes: 127
From: Middle of Kansas
Default

Thats my thought also. If the valve seals were leaking it would show up in the exhaust. Not the intake. Sounds to me like when the vapor vent line to the carb gets oil in it. It could be the umbrella vent valves in the head are bad. If your valve seals were leaking, you should see a lot of smoke when you decelerate. Are you sure it is oil smoke, or could it be gas from being to rich. Just a few thoughts.
 
Reply
Old Apr 5, 2011 | 08:09 PM
  #10  
dan conner's Avatar
dan conner
Ultimate HDF Member
Joined: Apr 2010
Posts: 5,308
Likes: 9
Default

a valve stem is on a tire...how can it leak oil? lol.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
harleytq
Engine Mechanical Topics
5
Jul 23, 2019 06:20 PM
Fatkid1979
Touring Models
5
Sep 27, 2018 06:15 PM
misfitJason
Engine Mechanical Topics
4
Dec 27, 2015 06:51 PM
chopperNeil
EVO
9
Mar 30, 2012 09:47 AM
tc
EVO
2
May 2, 2011 10:35 PM




All times are GMT -5. The time now is 07:13 PM.

story-0
7 Times Harley-Davidson Chucked Tradition Out the Window

Slideshow: Harley-Davidson built its reputation on nostalgia, but every so often, the company took a hard left turn into the future.

By Verdad Gallardo | 2026-05-20 11:18:19


VIEW MORE
story-1
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-2
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-3
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-4
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-5
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-6
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-7
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-8
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-9
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE