Sequeal to leaking rocker boxes

[Panzer]

I've read a few more cases of sporty rocker boxes leaking in different year bikes, other then the ones mentioned here in the Sportster section.
Can anyone explain why these box gaskets are leaking.
I think you'll find (if you ask) that all the boxes that leak were still tight as far as the mounting bolts go.
Mine started to leak after 5 years, some sooner and some later.
What gives?

[mokeypoole]

every one I ever had to replace on mine were due to the old, two piece style paper gaskets below the bottom box.  Now they have a new, one piece metal design gasket for that and I think the problems have declined.

The 2007 I am going to work on this weekend is leaking for what I have witness several times before.  The owner switched from Dino to Synthetic oil.  It started leaking within  one month and 500 miles from the oil change.

I know some are going to say the leak was there before, the synthetic oil just uncovered it but I think it would not have been leaking for a few more years

[Panzer]

I think you'll find that the 07 and up seals (gaskets) are preformed and fit into a grove, both outer and inner seals.

[splineman]

My 05 started to leak at the head gasket and  I bought a Cometic top end kit. All the gaskets were oil tight except the outer (top most) rocker cover, the rubber one, the Cometic one leaked and didn't fit very well.
I went and got the newest Harley OEM formed gasket and problems solved.
One thing I discovered is that Harley have revised the outer rocker box casting twice. The latest is Rev.2 and they have added a small amount of casting material to bolster the gasket next to the rocker shafts. There is a tech sheet on it that I have attached.
Hope this info helps.

[attachment removed after 60 days by system]

[WhipLash96]

My Sporty is a 96 and I have not had one single issue with any kind of leaking that was not my doing. I have had the jugs off before and all Cometic stuff on now and still no issue. I hope you get it all worked out. 

[Karl H.]

I think you'll find that the 07 and up seals (gaskets) are preformed and fit into a grove, both outer and inner seals.

MoCo changed the material of the rubber gasket. It's now stiffer and dark grey instead of orange (17362-07B, 17695-07B).


Unfortunately there are ugly casting fins on the sealing face at the bottom of the gasket groove (see pic). The gasket might not be able to compensate for that. I assume that the oil passes the gasket at that fins and flows to the lowest point of the groove where it gets visible (front corner of the front rocker box, rear corners of the rear rocker box)


The used gasket shows marks where the fins are located in the groove:


The oil gathers and seeps out at the lowest point of the groove:


Karl

[BrianK]

My wife's 07 Nightster did this.  Dealer repaired under warranty, so I don't know what the fix was.