[TCP]

Ordered oil filters and from my dealer.

They sent me 3 O-rings to go with the 3 filters I ordered.

The O-rings were intended for the filter cover.

Did the oil change, and when I went to put the new O-ring in the filter cover groove, the thing was just too big in diameter to wquash into the groove.

Simple error on their part I thought, so I closed the job with the original O-ring.

No problems, leaks or issues.

Called the dealer and explained that the O-rings were too big in diameter to fit in the groove without buckling. 

They sent me an O-ring kit with various sizes.  The only one that was close enough in size to fit the filter cap was the exact same size as the one that wouldn't fit before.

Anyone having any O-ring issues out there???

The Caseman

[TWinOKC]

I got some O-rings for the filter cover at Ace Hardware.   Take the cover down there with you to get a good fit.  Cost is something like 3 for a dollar.

   

[Ducati Scotty]

The C5 and G5 have different covers for the filters AND different size o-rings for the covers that fit differently.

The G5 cover has a bit of a cylinder extending inward that fits into the opeing in the side cover.  The little cylinder section has a groove in it and the o-ring sits in there.

The C5 cover is a bit larger and flat.  The o-ring sits in a groove on the inner face of the plate.  None of the cover protrudes into the sde cover near the seal.

The G5 o-ring is smaller in overall diameter but the ring material is thicker, maybe 3-4mm.  The C5 o-ring is a slightly larger overall diameter but the ring material is smaller, maybe 2mm.  Once you see both of them together you can tell which is which.

I'm guessing you got the wrong one.  Go back and bring your original.

There's usually no problem reusing them if they're still supple and not cracked.  And the filter one is easy to replace later with minimal spillage if it does leak.

Not sure where the B5 fall, which side covers does it have?  The older looking style with the wings are C5.

Hope this helps.

Scott

[TCP]

I have a C-5, and the O-ring I received was still too big.

Looks like a trip to the hardware store is in order.

I don't have a dealer anywhere near me unfortunately.

My parts are being shipped in.

Thanks for the responses.

Caseman

[GlennF]

Not sure where the B5 fall, which side covers does it have?  The older looking style with the wings are C5.

Hope this helps.

Scott

My B5 oil filter cover has 3 bolts and the spring and pressure plate are attached to it as a single unit.

[Ducati Scotty]

That sounds like the C5, that's what I thought it was.

I'll have to measure all my o-rings next time I do an oil change.

Scott

[Maturin]

I may add that the o-ring is the crucial part to keep it tidy, the paper gasket around the cap is not strong enough to hold the oil back when the o-ring is done. According my experiences it can be used twice in case of an emergency but won´t survive a third intervall.
Unfortunately I don´t know which o-ring fits the C5, looking after this part at Hitchcock´s I found four different ones and all of them are labeled to fit both G5 and C5! Would you mind measuring diameter and strength, HTC? It´s interesting to get an overview over the differences between the versions. Regards

[TCP]

The one I was sent for C5 measures 2 1/4" OD and has a thickness of approximately 1/16".  Looks like it should have been 2 1/8" OD and it would have worked fine.

[indyogb]

I got the 5 filter kit, and it came with a slew of gaskets and o-rings, only one of which appears to fit on my B5.  The one size does seem like it fits in multiple places (all the o-rings appear to be the same size, except for the filter cover).  I'm going to see if I can't find a supplier for just the o-rings and work it out that way.

[Arizoni]

When looking for a replacement O-Ring, remember that you can stretch them slightly larger to fit on a shaft or in a face seal application.

The groove in a shaft or a face seal is designed to be slightly larger than the loose packings inside diameter so the inside diameter will always be slightly tight.

If the packing is intended to be used in a bore, the bores size will be slightly smaller than the installed stretched packing in the shafts groove.

This slightly smaller bore will squeeze the packing forming a tight fit.  The width of the O-Ring groove is wide enough to allow the packings squeeze to flow outward into the side clearance.

In a face seal application it is the squeeze between the bottom of the face groove and the mating flat surface that seals the joint.

In a face seal, the larger diameter of the groove is sized to allow the squeezed packing material to expand into it.  In other words, the cross sectional area of the groove is always larger than the cross sectional area of the packing.

Even when a face seal packing is sealing internal pressure which will try to blow the packing outward during operation the packing groove is designed so that the inside of the packing is the tight fit.
At the pressures seen in the Royal Enfields oil system the packing in a face seal (if one is used) will still be sealing on the face of the mating part and the bottom of the packing groove.  It takes well over 200 psi to cause the packing to start to move outward towards the outside diameter of the groove.

During assembly, if the packing clears the inside groove diameter and is compressed against the outside groove diameter it will usually seal poorly or not at all. 
For this reason, you cannot buy an oversize O-Ring and cram it into the groove and expect it to work.