Filter cover oil leak

[Jack Leis]

Hey guy's , I'm looking for some help here. 2011 G5, 17,000 miles, No real problems until about 6 months ago. It seems that everytime now when I change my oil  and filter I get a small leak from the gasket after about 200 to 300 miles. I clean the mating surfaces well and have had some luck with permatex grey . About 300 miles ago to fix the leak I cleaned the surfaces , applied some grease to both sides of the gasket and bolted it back. Sealed like a champ. I thought. Yesterday I went for a few short errands, rode it maybe 5 miles total and sure enough, started dripping again. I cant help but wonder if the cover is slightly warped or if there is something going on like maybe too much pressure in the filter cavity. It's driving me nuts ! I'm reaching out for your thoughts on the subject. I'm at wits end !

[t120rbullet]

Try using 2 paper gaskets.

If not you might have to lap the cover in with some valve grinding compound if it did warp.
Make sure you get it 100% clean after using that method.

[Ducati Scotty]

G5 right?  Can't you just flip it 180 degrees?  Might seal better that way.  On the C5 there are 3 bolts and you can rotate 120 degrees.

Scott

[Jack Leis]

It leaks either way Scotty.

[barenekd]

Time to get out the magnifying glass and check for porosity or cracks!
Check both the cap and the underlying structure.
When I was working in the Triumph shop, we had a 500 that kept coming in with an oil leak at the cylinder base. the guy who did the warranty work ahd regasketed it several, when I figured it was time for a closer look. The cylinder base had a small porosity hole in between the cylinders. Fixed that and it was never to return for the leak.
Bare

[Ducati Scotty]

Have you replaced the rubber oring on the filter cap?  Not the paper gasket.

Scott

[Jack Leis]

EVERYTHING is new.

[Ducati Scotty]

Hmmmm....

On the G5 that inner o-ring is what really should do all the sealing.  If it's in good shape the paper gasket shouldn't even matter.

Have you taken a really good look at the filter cover?  Are there any tiny cracks?  It's not uncommon for them to get some on the ears if they've been overtightened.  Maybe one from the center bolt that holds the springs and plate?  Might be good to take a close look at the side case for cracks as well.

Scott

[Jack Leis]

It leaks from the gasket. The O-ring is tight as a frogs ass when inserting it into the oil cavity. The O-ring is always lubed with Motul when I'm reinstalling the cover. That is why I'm wondering if there could be too much internal oil pressure. Ive got a tough one here , I sincerely appreciate the advice Ive been given so far.

[t120rbullet]

That is why I'm wondering if there could be too much internal oil pressure.

What's been done to the engine that would increase the oil pressure ?
Take the right side cover off to replace the sprocket and goop it back up with RTV silicone ?

[Jack Leis]

You hit the nail on the head. I was very careful not to goop any passages when doing so. I am not a cub, Ive had motors apart in the past and never had an oil leak or any repercussions from doing so. That's why I am so frustrated. And you have my undivided attention. Do I detect an Epiphany ?

[gremlin]

drill it, tap it, & screw in a gauge .....

[Arizoni]

A properly installed O-ring in that cover will seal pressures up to 1500 psi internal pressure.
At pressures higher than 1500 psi the O-rings material will start to flow into the gap between the cover and the bore but I don't think we have to worry about that on a RE.

If the O-ring was the wrong thickness or diameter it will be hard to install and it will leak.

The correct thickness will easily fit into the slot in the cover.  It should have about .006-.015 total side clearance to the groove.
This clearance is reduced when the O-ring is installed because the squeeze on the O-rings inside and outside diameter will deform its shape and the O-rings material needs a place to grow into.  The clearance gives it the space.
  If it won't slip easily into the groove it will leak when it's installed.

The diameter of the installed O-ring when it is on the cap  (before installation) should be .010-.022 larger than the inside of the bore where it will rest.  If it is larger than this it will be very difficult to install and will probably leak.

The inside diameter of the O-ring is always smaller than the groove diameter it fits on.  This gives it a slight stretch when it is installed.
A O-rings inside diameter that is slightly smaller than the recommended size will often work but a O-ring that has a larger inside diameter  than  the bottom of the groove it is installed on will always leak.  This condition is easily detected by seeing if the O-ring moves freely after it is installed into the groove.  If it does, it will leak.

Of course, any nick or irregularity in the inner or outer surface of a O-ring will cause a leak.
A nick on the inside of the O-ring can be caused while putting it carelessly over the sharp edges of the groove while installing it on the shaft but this seldom happens.

The sharp edge of the chamfer (or lead in) leading into the filter cavity can nick the outside of the O-ring during installation.  It only takes one small nick to cause a leak.

This is fairly common in all O-ring installations and it explains why the jet engine company I worked at for 40 years had a  specification created that required the removal of the sharp edge of the chamfer meeting the bore, it being replaced by a small polished radius with no undercuts permitted.

Anyway, I would look for a replacement O-ring that is the right size and gently round off the lead in chamfer in the housing before installing the new O-ring.
I'm sure this will fix the problem.

[Jack Leis]

Thanks Jim ! Regarding the chamfer, I did that months ago. What I did just do is installed an o-ring and gasket that I recently got in a Hitchkock's care package. The gasket was of better quality than that of Nfield gear and the o-ring is beefier as well. Its getting ready to rain here so I'm going to have to wait for the results but just idling in the garage it is holding it's own. Thanks for all the input. I love this forum !

[Arizoni]

As I mentioned above, beefier is not better.
To work right, the O-ring must be the right size.

Too large of an inside diameter, too thick of a cross-section or both will doom it to failure.