Oil leak into outer timing case

[Phil C]

Evening all,  Anybody at a loose end this evening and fancy mulling over some more of my basic-level questions?  Three things I hope you experts might be able to help me with.

1. Some of you might remember that for some time now I've been trying (on and off) to locate the source of a leak.  Actually I think it's two leaks. One, which appears to be only slight, manifests itself as a few vertical dribbles on the inboard side of the primary chaincase.  The other appears to be gear oil seeping slowly from the joint face at  bottom of the outer timing cover. That's the one I'm investigating.  I took the outer cover off today, and inside was about a cupful/mugful of oil which looks like gear oil (greenish with the orange tint of the dye I used.)  Please have a look at the photos. Where do you reckon it's coming from? Any advice please?

2. Also (see other photos) what is the piece of bent wire which goes through a hole in the inner casing and is bent at right angles each end (and pointed at one end)? The photos are one of each end of it.

3. I was expecting to see a breather hole at the top right of the inner casing.  But I don't see one.  Should I be able to?

Thanks in advance, as always.        Phil.

[Phil C]

By the way, I should have said, the wire is next to the gear lever spindle.  Phil

[Phil C]

Just had another look. There's quite a bit of oil - more than a mugful, I'd say. At first I thought it must be coming from the bottom shaft, but there is a bit of it amongst the ball bearings on the top one, so I'm not sure. I guess it could have splashed around a bit, but the bike hasn't been ridden for a few weeks.  Presumably it's a failed oil seal?  Phil

[Phil C]

Further thought about the extent of the leak: I guess it could have been accumulating for a long long time if it wasn't escaping from the outer cover very quickly.

[Colin SS90]

1 - Looks to me as if it's leaking out of the kickstart bush as there is no seal there. Perhaps the bush is worn.
2 - The bent bit of wire is securing the gearchange quadrant spindle, should be a split pin.
3 - Not sure about breather.

[Phil C]

Thanks Colin.

Do other people agree it's the kickstart bush? If so, there are more than one on the Draganfly drawing. I guess it would be the first of the ones I've listed here?
40-3270 kickstart bush (I think that one is outermost, and is top hat shape)
40-3024 kickstart shaft bush
40-3272 kickstart ratchet bush

Phil

[Colin SS90]

Just had a thought, was the oil level in the gearbox correct? If it was too high it would leak through the upper ball bearing.
If you can wait a while why not set the oil level to the correct height in the gearbox, clean off the excess oil and wait for a few days to see if it leaks and where from.
Can't get on Draganfly site at the moment, I'll try again later or look at parts book.

Good luck.

[DAVE BRADY]

Hi,

It is a while since I had a B40 so going from memory.
The part of the case that covers the kickstart etc is not sealed from the gearbox and oil will come through by the gear selector plate, kickstart shaft, splash though the main shaft bearing hence the gasket.  Looking at the photo it looks like the oil was about right and was contained in the rear part of the case/gearbox.  The front part of the case looks quite clean so the gasket was doing its job.  So if we accept that oil should be in the rear of this case, the places it can seep out are the gear change shaft and the kickstart shaft.  There is a seal 40-3281 shown in the parts book on the kickstart shaft so this must in good order.  As there is no protection on the out side it is inevitable that there will wear from road dirt hence a bit of wear and a weep of oil.
I hope this helps.

Dave.

[Colin SS90]

Hi,
From the parts book it looks like the bush is 40-3270.
The breather should exit via a boss adjacent to the points wire exit on the inner cover through a small tube.
Hope this helps.
Colin

[Phil C]

Re gearbox being overfilled: I see your point, Colin, and will check that, but can't imagine how that could have happened. Re oil being expected in the outer casing, should there really be that much? By the time I took the photo much of the oil was in the drip tray, out of shot. More than a mugful of oil, I'd say. Should there really be that much in the outer casing?  Phil
PS brrr... cold in the garage this morning, drained the drip tray into my waste oil container, it was very thick at that temperature. Came in whilst I could still feel my hands. Must get a heater!

[Phil C]

Hi,
From the parts book it looks like the bush is 40-3270.
The breather should exit via a boss adjacent to the points wire exit on the inner cover through a small tube.
Hope this helps.
Colin

Thanks Colin. Yes I have that breather. Actually I meant a breather into the outer case from the crankcase. Sorry, should have made that clear. Maybe mine doesn't have or need one. Phil

[DAVE BRADY]

Hi Phil,

I am fairly sure that there is a hole at the bottom of the case just behind the kickstart mechanism.  This connects to the main part of the gearbox and so the oil level is the same hence the oil line on your case.
Seal 40-3282 goes on the outer side of the case in a recess just behind the kickstart lever.  It is possible that some B40F did not have this seal as it may have been a mid season modification.

Dave.

[Colin SS90]

Hi Dave,
Following on from what you said, does this mean that there should be oil between the inner and outer timing covers at the same height as that in the gearbox? If so then the source of Phils leak must be the gasket between the inner and outer timing covers.

Hi Phil,
I remember reading somewhere that the crankcase breathes through a hole the camshaft into the outer timing cover.

Colin

[Phil C]

I didn't know there should be oil in the rear part of the outer case, to the same level as in the gearbox.  If that's the case (no pun intended) then I guess the only way it's leaking is at the outer casing gasket, ie from the rear part of the outer case out to the outside.

I now see the hole at the bottom of the rear part, thanks Dave.  You say that as the front part is clean the gasket must be doing its job.  Er... what gasket? Should there be a gasket between front and rear?

I take it the seal you're talking about is 40-3281?

Also, please have a look at the photos everyone.  I found these in the bottom of the outer cover, amongst all the thick oil.  I think they might be from the ratchet.  I guess i just get a new one, undo the nut, and change the ratchet?  Is it that simple? What might have caused this?

Phil
PS I'm learning, thanks to this forum.  And I'm enjoying it.  Apart from the icicle on the end of my nose!

[Phil C]

Hi Dave,
Following on from what you said, does this mean that there should be oil between the inner and outer timing covers at the same height as that in the gearbox? If so then the source of Phils leak must be the gasket between the inner and outer timing covers.

Hi Phil,
I remember reading somewhere that the crankcase breathes through a hole the camshaft into the outer timing cover.

Colin

Colin, I don't get what you're saying about my leak being the gasket between inner and outer covers?   Phil