Author Topic: head gasket leak, pucks or rocker cover gasket leaks, crank breather  (Read 772 times)

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Offline evinrude7

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noticed early spring 2020, a leak from the head gasket on both sides as shown by photos.  they were minimal and seemed to stop so i left them alone.  took a continuing ed motorcycle class yesterday and noticed the drips again.  they seem to roll down to the front of the top fin on the head with a little bit blowing back on the top fin of the head.  today i degreased those areas with the hope of using a syringe to squirt a little high heat gasket sealer into where the leaks appear.  as i was cleaning i noticed burnt oil within the plugs 1 and 4 cavities.  last winter i changed out the pucks and thought i did the job correctly as the motor hasn't had much if any burning oil smell since then, until yesterday.  oil has not made it to the header pipe clamps like it did before i changed out the pucks when it was a real mess. 

where i am pointing to the head gasket in the photos i notice a gap in the gasket on both left and right side.  that is where it seems the leak is occurring as far as the head gasket goes.   because the gap is on both sides it would seem to me that is by design...however the leak is definitely coming from there. 

my thoughts on the plug cavities being dirty are pucks or rocker cover gasket at the front corners.  really hoping it's not pucks but i can pull the motor this winter if i have to and if i do i may dig deeper.  for now i'm going to try and squeeze a bit of sealer into those sides at the head gasket. 

lastly, how much oil residue should be on the end of crank breather hose?  it's not dripping but since winter i've put plenty of miles on the bike and the tip of the hose is dirty with black residue.  is this normal?  no blue smoke or white smoke from the exhaust. 

any info or suggestions appreciated.  edit: photos are post degreaser.
« Last Edit: August 09, 2020, 09:21:16 AM by evinrude7 »
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Offline BoneDigger

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #1 on: August 09, 2020, 10:03:47 PM »
With oil in the spark plug wells it has to becoming from the head rather than the head gasket.  Your pucks or oil passage o-rings are likely the source. As for the little gaps in the head gaskets on the side, those are part of the gasket design - likely in their manufacturing process. 

Offline evinrude7

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #2 on: August 10, 2020, 06:19:42 AM »
With oil in the spark plug wells it has to becoming from the head rather than the head gasket.  Your pucks or oil passage o-rings are likely the source. As for the little gaps in the head gaskets on the side, those are part of the gasket design - likely in their manufacturing process.

thank you
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Offline Alan F.

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #3 on: August 10, 2020, 09:31:16 AM »
What brand head gasket did you use?

Offline seanbarney41

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #4 on: August 10, 2020, 04:02:01 PM »
Dont ignore the easy stuff like your tach drive seal and the tappet inspection covers.  I have seen leaks here run down to the top fin, run down into spark plug holes etc .   its really tricky.  I have even seen some trick of aerodynamics cause oil leaking from the back run to the front.  Sometimes the leak will quickly burn off a hot valve cover leaving it to look leak free while all the oil that ran down pools up around the head gasket.
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Offline BoneDigger

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #5 on: August 10, 2020, 04:21:12 PM »
Here is a pic of a gasket I got from 4into1 (no brand name attached to the packaging) with small cut outs on both sides. While it may look like there is part of the gasket missing, it is just an artifact of the maker’s manufacturing process.

Offline evinrude7

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #6 on: August 11, 2020, 06:33:56 AM »
What brand head gasket did you use?

didn't change out the head gasket. 
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Offline evinrude7

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #7 on: August 11, 2020, 06:37:46 AM »
Dont ignore the easy stuff like your tach drive seal and the tappet inspection covers.  I have seen leaks here run down to the top fin, run down into spark plug holes etc .   its really tricky.  I have even seen some trick of aerodynamics cause oil leaking from the back run to the front.  Sometimes the leak will quickly burn off a hot valve cover leaving it to look leak free while all the oil that ran down pools up around the head gasket.

tach drive seal is new.  looks super clean around there.  had the tappet covers off sunday to adjust tappets.  tappet covers for 1 and 4 are newer.  replaced a couple years ago.  not noticing any leaks there. 
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Offline evinrude7

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Re: head gasket leak, pucks or rocker cover gasket leaks, crank breather
« Reply #8 on: August 11, 2020, 06:50:22 AM »
Here is a pic of a gasket I got from 4into1 (no brand name attached to the packaging) with small cut outs on both sides. While it may look like there is part of the gasket missing, it is just an artifact of the maker’s manufacturing process.

that's what i was suspecting.  perhaps it's the pucks then.  with it clean i'll powder up the areas and take it for a long ride.  maybe it will point me to the leak.

still wondering if the end of the breather hose should have oil soot on the outside.  maybe about 3/4" up from the end.  like i mentioned been riding all year since the motor was last out and reinstalled so i haven't cleaned it.  guy behind me at the motorcycle course on a gsxr was complaining about an oil smell.  thus i checked the hose as well.  on all of my vehicles the breather tubes generally had some oil coating in them.  granted i've never owned a new vehicle but my days of driving beaters are long gone. 
« Last Edit: August 11, 2020, 06:52:37 AM by evinrude7 »
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