A leaking oil filter cover.

[mralistairjones]

That o-ring isn't compressed at all and should be after a few 1000miles.
I thought that was a shim under the black o-ring in your pic Eyesight might be defective. If so, it should be on the other side if needed for the year model. Apparently not though.

Understood. That’s the gasket which so I’m told is not required along with the shim on post 1990 machines.

[Kurt in S.A.]

As has been mentioned, the various components used in the filter housing depends on how far inside the engine the canister is. The white o-ring (not sure about the back o-ring) is 4mm in diameter. If the gap between the case and the canister is 3mm, then the o-ring would be squeezed from 4mm diameter to 3mm diameter or 25%. That is the upper goal for this setup. If however, the gap is 3.5mm, then the o-ring will be squeezed to 3.5mm in diameter which is around 12%. This is a good lower goal. If however, the gap is less than 3mm, then the o-ring will be over-squeezed and it could rupture. If the gap is larger than 3.5mm, then the o-ring won't be squeezed enough and the oil pressure in the system could be compromised.

So depending on your canister depth, a stack up of components can be determined. If as you say you had no metal shim and the o-ring wasn't distorted at all, that suggests that your canister is deeper than standard. Or it could just be the gasket which effectively reduces compression of the o-ring. In fact, my calculations show that with just the o-ring and the gasket, and with a 3.5mm canister depth, the o-ring has a 0% compression.

Kurt

[SteveD]

Understood. That’s the gasket which so I’m told is not required along with the shim on post 1990 machines.

It might be an shadowy illusion to my eye...pink looks like a shim. Orange is gasket, blue is o-ring...but you knew that

IMG_8314.jpeg (1.39 MiB) Viewed 614 times

[mralistairjones]

Understood. That’s the gasket which so I’m told is not required along with the shim on post 1990 machines.

It might be an shadowy illusion to my eye...pink looks like a shim. Orange is gasket, blue is o-ring...but you knew that

IMG_8314.jpeg

That is an incredible observation, and if I did not know better then I would have agreed with you that was a shim. However, it must just be how the photo was taken because there honestly was no shim fitted.

[barryh]

@barry
In reference to your advice of feeling for 'some resistance before the cover fits flush' in your previous post. To my feel, when I hold the cover in place there is no resistance ... in fact it appears to me that the cover fits flush with the engine casing immediately.

There is your problem then, the O ring wasn't being compressed at all.

Remove the gasket and try again. You should then feel some resistance. If it's Ok replace the filter and reassemble without the gasket. use the new white O ring that came with your filter.

[mralistairjones]

@barry
In reference to your advice of feeling for 'some resistance before the cover fits flush' in your previous post. To my feel, when I hold the cover in place there is no resistance ... in fact it appears to me that the cover fits flush with the engine casing immediately.

There is your problem then, the O ring wasn't being compressed at all.

Remove the gasket and try again. You should then feel some resistance. If it's Ok replace the filter and reassemble without the gasket. use the new white O ring that came with your filter.

I like this plan Barry, thank you. I just measured the distance between the engine casing and the cannister, the measurements average 3.5mm.

The MAHLE filter that I have is different to what came out of the bike. Stupid question but could you advise which end goes in first. I assume it is the end with the printed text on it.

[Kurt in S.A.]

I believe the OX36 filter is for the cooler-equipped bike. I think you want an OX37 which has rubber grommets on both ends.

Given that you see 3.5mm on the canister depth and with my math earlier, no gasket, no shim, and white o-ring should get you reasonable squish of the o-ring. Monitor the amount of resistance you get when reinstalling the cover without filter as Barry has said. If you see that it takes something of a push to get the cover flush to the case, then insert the filter and put it all together.

Kurt

[barryh]

That's what we call the two part bendy filter which is easier to fit on some models. It will be fine for yours if it fits and seals. It doesn't matter which end goes in first provided there is a rubber seal at both ends and in-between the two filters.

If you want to be sure it's sealing do another 30 second trial fit. This time install the filter and offer up the cover but without the big O ring. Any resistance you feel before the cover fits flush will now be due only to the filter seals. If the filter is the wrong length this test will show it. If you want to check the filter length before using it, the overall distance between end seals should be 128mm.

[mralistairjones]

Thank you gentlemen.

I have just discovered that the OX36 filter, which I was lead to believe was the correct one for the bike does not fit. So I'm about to order the OX37. Frustrating but there you go.

[mralistairjones]

Just checking back.

The OX37 filter is in and the cover back on.

So more unchartered territory for me but I assume the next steps are.

1. Fill the bike with oil
2. Remove the cables from the sparkplugs
3. Turn the engine over until the red oil light is not lit
4. Fit the cables back to the sparkplugs

Did I miss anything?