Rupert Ratio (vol 1, p.125) says " For some reason the rubber lip of the seal has a propensity for wearing a groove in the early type bronze sleeve bushes; result, another leak. The only permanent cure for this is to change the one piece bronze item for the later two part steel- backed items."
Would I be able to see any such groove by removing the clutch and the back plate and sprocket? And I guess replacing the bush would mean removing the gear cluster (from the timing side, presumably)? Phil
With the chaincase backplate removed, you should be able to see whether the bush is grooved. What slightly confuses me with these bushes is that some of them are split down their length presumably to make insertion easier. The picture shows bush 41-3045. If the bush is split like this, I find it hard to see how this is going to seal properly or prevent unnecessary wear in the clutch seal. Might be worth looking closely to see if your outer bush is split. Unfortunately, you have to take the gearbox apart to replace these bushes.
Thanks, AWJDThumper. When you say chaincase backplate, do you mean the circular plate behind the clutch - the one that's held in place with BA screws? Phil
Yep - Looking at the parts book, the official title is cover plate!
Here is a photo from when I had the clutch off in about June/July 2018 in search of the oil leak. There appears to be a groove. Looking back at what I said on this forum at the time, when I slid the seal over it, although it was a very easy sliding fit, I could feel no play. And I guess it would be a slightly tighter fit once it had been pressed into the circular plate. But I wonder if it would loosen as the bike heated up.
Does the fact that a groove is visible mean it's a likely source of a leak? Should I replace the bush?
Phil
I'm not familar with this set up but the split bush is a DU bush. They normally press into a housing and remain static with the shaft in the bore rotating hence the coated lining. A split bush will never seal on its OD and only wear the oil seal out more quickly. The split is there to help distribute the oil along the length of the journal internally.
A plain rotating bush will still wear a flat on a single lip seal, which over a much longer time will leak. They also age harden and leak. Modern seals are more forgiving. Depending on available space it may even be possible to fit a double lip seal which would help no end and counter the wear track from the original single lipped seal. The mark is probably just "polished" unless a distinct groove can be felt. If it is a poish mark a new seal would probably cope with it and seal.
In such an application, usually, the bush if rotating inside the oil seal would be hardened and plunge ground as the oil would track down a conventionally ground bush.
If the bush is a pressed onto the shaft, it should have a smooth outer and be a slight interference fit.
Thanks, Rick, but I'm sorry to confess that quite a bit of that I didn't understand. Remember I'm a novice at this. But enthusiastic and keen to learn.
At the time I took the photo, two years ago, I fitted a new seal, which was a loose slide fit but without any discernible play. Didn't cure the leak.
Should I remove the clutch again and have a close look at the groove/ mark?
Any thoughts, anyone?
Phil
No probs Phil. Don't worry about the terminology.
As I said, I'm not familiar with this part of the bike. I assume the oil seal is stationary in the cover plate and the shaft rotates inside it. Is there a bush on the gearbox output shaft? Does it have a longitudinal groove as AWJD said? If there is a bush it can be changed to eliminate the groove. It would also be possible to get a new plain bush manufactured and hardened locally by a local engineering company. Cheaper to measure the outside and inside diameters plus length of it and go to a local bearing supplier. They have catalogues of variations of that diameters in many formats. Very cheap too. We've got to determine too what you need. If the bush is on the shaft it should be a snug fit otherwise oil can track through it internally.
Did you consider the oil level screw? Easiest and cheapest to check.
Also the seal. The size will be written on it in raised letters, for example 11/4" x 7/8" x 1/4" meaning outside diameter, inside diameter and thickness. Again the jolly old bearing supplier will have catalogues of seals. You may be able to find one of the exact dimentions but be double lipped as opposed to single lipped - meaning twice the sealing capabilities, or alternatively be able to accomodate one slightly wider depending on how the seal is retained.
For the amount of work involved could you put up with it until you need to strip it all down? I'd be happy to walk you though the steps when the time came.
Thanks Rick. I'd feel much happier if I knew for certain exactly where the leak is coming from. Phil
I would definitely confirm where the oil is coming from first - as said, use either dye or red coloured ATF oil to do this. My money would still be on a gearbox leak though.
I'm not sure that a small groove in the 4th gear pinion bush would cause the leak provided a new seal was fitted at the time. Sometimes, you find that the outer bush is slightly displaced outwards and it might be possible to tap it further into the pinion moving the groove away from where the seal contacts it. Might be something worth considering before you take the gearbox apart.
Okay, thanks, well I think I might try again wiping off any oil that's showing at the moment, then draining the pc, and going for a ride with it empty. If there's no leak evident when I get home then that should tell me it's pc oil that's leaking, not gearbox. I've done this once but I guess it won't do any harm to do it again. How far can I ride with an empty pc without causing any damage? Would about, say, three miles be okay? Phil
Further to my post of a few minutes ago, I've also just ordered some dye. Phil
Hi Phil
The new replacement bush is in two parts. The part nearest the clutch should stick out 3/8". This rotates inside the gearbox sprocket cover oil seal which will wear because of the split. The split should allow a tiny amount of oil to penetrate which should reduce wear. Because the outer shell of the bush is steel there should be little wear in this. The felt washer is quite often missing on these bikes. This will take up some oil and prevent grit getting into the oil seal. Have you checked whether oil could be getting around the layshaft bush (just below and behind the bottom teeth of the gearbox sprocket in the photo. Note the felt washer.) The layshaft bush sits below the oil level of the gearbox.
For some reason the photo has reversed itself so don't let it confuse you.
Quote from: Phil C on 14 Jul, 2020, 09:03
Okay, thanks, well I think I might try again wiping off any oil that's showing at the moment, then draining the pc, and going for a ride with it empty. If there's no leak evident when I get home then that should tell me it's pc oil that's leaking, not gearbox. I've done this once but I guess it won't do any harm to do it again. How far can I ride with an empty pc without causing any damage? Would about, say, three miles be okay? Phil
I don't think a 30 minute ride is going to do any harm with no oil in the chaincase!
From an engineering point of view, it's difficult to see how significant oil can seep out of the chaincase unless there's a gross problem with a seal. It's not as though it is pressurised or there is huge amount of oil in it (140 cc)!
However, this can change if the LH crankshaft seal is not doing its job. If this was the case, it would not only lead to pressurisation of the chaincase but could also let engine oil leak into the chaincase increasing the amount of oil there. I thought I read earlier that you might have found more oil in the chaincase than you expected which might be due to someone putting the wrong amount in but could be due to a leaking crankshaft oil seal. The way to check whether the chaincase is being pressurised is to remove the clutch adjustment plug, run the engine and see whether you can feel any pressure pulses out of the hole.
Hmmm... don't like the sound of that. So I should drain the pc, remove the clutch adjustment plug screw, start the engine, and put my thumb over the hole? Is that right?
Is the crankshaft seal a big job for someone like me?
Thanks again for your help. Phil
Further to my post just now, when I drained the pc the other day there was 1/2 pint in there, to my surprise. I couldn't understand how I could have put that much in. Phil
Do the test and it should be obvious if the crankshaft seal is blowing. It's not a big job to replace - just need to remove the alternator to get at it. If you put the correct amount of oil in to start with and it then ended up with 1/2 pint then a leaking seal could well explain it!
Excuse my dimness please, AWJDThumper: you say it should be obvious if the crankshaft seal is blowing. Obvious in what way? Phil
The engine will generate pressure pulses (puffs of air) which you should feel coming out of the chaincase hole
Update: just now I drained the pc, removed the clutch adjustment screw, started the engine, and placed my fingers at the hole (loosely, as it's quite a big hole to completely block.) I didn't feel any puffing. Does that rule out the crankcase seal ( despite the overfull pc mystery)? Phil
Good afternoon Phil,
I have copied and attached your image of the leak/drip. This reminds me of a similar issue on my wife's '51 Flash. The problem turned out to be the gearbox oil seal behind the sprocket although a leak around the layshaft bush, as has been mentioned, could produce a drip in the same place.
The drip appears to be on the bottom of the gearbox and to be in this location is unlikely to have come from the primary case or the main shaft bush seal as this drip has almost certainly emanated from behind the sprocket.
I think that you said that you replaced the gearbox seal not that long ago so the seal has either failed prematurely or oil is finding its way past where the seal sits in the case - this is not unusual.
Perhaps a plan of action could be to remove the clutch and the sprocket to see if oil is seeping past the edge of the seal where it sits in the case. Two options come from this. Either remove the seal and refit the used seal after a thorough cleaning and the application of a bit of silicon where the seal sits against the case or do the same but fit a new seal to save having to do it again later.
Dave.
Quote from: Phil C on 14 Jul, 2020, 15:31
Update: just now I drained the pc, removed the clutch adjustment screw, started the engine, and placed my fingers at the hole (loosely, as it's quite a big hole to completely block.) I didn't feel any puffing. Does that rule out the crankcase seal ( despite the overfull pc mystery)? Phil
It should do but, if you find excess oil in the chaincase again, it might need revisiting!
Thanks Dave. But I'm finding it hard to believe the leak is gear oil, given that when I drained the primary chaincase (pc) and then went for a short ride, when I got home there was then no sign of a leak.That suggested strongly to me that the leak was from the pc. I'm going to try it again with s bit longer ride. If when I get home there is no sign of a leak then surely it must be coming from the pc? Do you see, on the photo, the vertical dribbles down the chaincase wall? Phil
Hi Phil,
Yes and I see that you did mention that you had wiped some oil off so less evident. Perhaps then remove the clutch etc. and do as suggested but also revisit the seal in the plate behind the clutch as well.
If it looks like the layshaft bush is seeping a bit of oil, there is a product that can effect a cure.
Oyltite Stik is rubbed in to the offending joint/seam and dries to cure the leak.
I got mine from www.frost.co.uk
Dave.
Good morning all. Well, not so good here really so far. Having drained the pc (with bike on side stand), this morning I went for a ride - just a few miles. When I got back I eagerly peered under the bike, expecting to see no sign of a leak. No sign of a leak will confirm the leak is from the pc, I thought to myself. I was almost confident. But, alas, the tell-tale dribbles were there. Not a lot, but definitely present (see photos.) So the source(s) of the leak is/are still a mystery. My oil dye has arrived this morning, so I guess I'll refill the pc with oil + dye, go for a ride, and have another look. I guess there might be more than one source.
There is a leak at the tap on my oil feed pipe, which runs down the rubber pipe, but I don't think that is relevant to this.
Any thoughts please?
Phil.
Further to my post from earlier, maybe I should put the dye not in the pc but in the gearbox? The dye is the stuff from demontweeks, via the link kindly provided by AWJDT. It says it's for engine oils and fuel, so hopefully would be suitable. I would love to solve this mystery and stop the leak.
Phil
It's difficult to see the oil in the pics but I assume it is the multiple brown streaks on the back of the chaincase? If so, it looks as though it is running down from around the rear cover plate joint - it may not be leaking from there but is running down on to this joint before spreading?
I would definitely advise putting the dye into the gearbox - that's probably where the leaks coming from but, if not, it would be good to rule it out. It should be much easier to solve a chaincase leak!
Thanks for sticking with me on this. You might remember that this morning, after a ride with an emptied pc, there was a dribble. Here is the latest: this afternoon I refilled the pc, put dye in the gearbox, and took the bike out for a ride. When I got back, this is what I saw. You can see a dribble again, but it doesn't look to me as though it has dye in it. To me, this doesn't make sense. And I imagine you're running out of things to suggest? Phil
Any chance of adding some graphics to the picture (eg using MS Paint) to highlight where the oil can be seen? If I were to guess, it looks as though it is running down the back of the chaincase to a drip underneath the suspicious looking hole that can seen towards the bottom of the chaincase! There also looks to be a brown stain from the cover plate to the same hole but it's difficult to tell whether this is oil?
Sorry, it's not very clear where the dribbles are. They're fairly thin dribbles and don't show up very well on the photo. I've wiped it now, because I smeared a bit of dyed gearbox oil on there in order to compare. (I don't think these dribbles are the dyed stuff from the gearbox.) But I can take the bike out again to produce more dribbles and take another photo.
In the meantime, this old photo from about two years ago is interesting. Maybe I've fixed some of this, but I guess the present leak is quite likely to be coming from where some of this stuff two years ago was emanating.
I could revisit the alternator wires grommet idea, but the present leak appears to be a vertical run which it's hard to think has come from the grommet.
Phil.
"And I imagine you're running out of things to suggest? Phil"
Not a chance, this is an internet forum. Stupid suggestions will never end. Especially during lock down, with nothing else to do.
It could be that the oil close to the leak is not yet contaminated by the dye. A long ride might show.
Had a bad leaking Burman gearbox. Solved it with filling it with the correct semifluid grease. Now almost oil tight.
Here is something I posted a couple years ago:
I wonder if there's anyone there who has been following this. Anyway, here is an update, and of course a plea for help. Having replaced the oil seal behind the clutch, and the one at the gearbox sprocket, I have put everything back together, refitted the primary chaincase cover, and today took the bike for a run, just eight miles. The leak is much, much less, but I see looking under the bike that it is still there. Please see the attached photo, taken from the right hand side side of the bike, so the front of the bike is to the right of the gearbox drain plug. Any ideas please as to where the oil is coming from? (you might remember the leak only happens when the engine is run.) Phil.
* IMG_20180827_145642.jpg (113.59 kB, 392x294 - viewed 84 times.)
I guess I improved it but didn't cure it. I might now do two things: 1. Go for a bit longer ride, and have a peep under the bike to see what colour the leak is, and 2. depending on what I see, go back into the primary chaincase. Phil.
Are you definitely sure the cover plate is not leaking?
You mean the circular plate behind the clutch? No, I'm not atall sure. Phil
But I did give it a good clean etc when I was in the pc two years ago.
Re the cover plate, 2 things:
1 if you've drained the oil in the PC there shouldn't be anything to leak from there.
2. If there's residual oil in the seal it could just be the remnants seeping out.
I'd continue to potter around without oil in the PC, gently of course, to see if the leaks diminish and or stop.
Hmmm, yes, thanks Rick, I might do that. Phil
. . . and finaly, this is a British bike. They leak, period. Never seen one that didn't. Years ago, in Bike magazine, someone wrote a list of dealer-speak phrases that were commonly heard by green bike buyers, an what they actually meant. My favourite was: " There are no real oil leaks, sir". This was due to there being no real oil in the engine. You have been warned, no leaks= no oil= sudden engine/gearbox death syndrome.
Hi,
They all leak?? Back in 1996 at the German Summer Camp at Langeleben they didn't. It was within a water catchment for drinking water so no oil could be dropped on the ground. Every bike was provided with a drip tray. All the drip trays stayed oil free except for the one under the old 'V' twin that had a total loss oil system.
I think I would say that they all could leak and probably have at some time, some do and many don't.
Dave.
Interesting. I was talking of the late 60's, to mid 80's, when brit bikes were being ridden as dailies, not immaculately restored at 4k each models, with all their seals done. Breathers were directed at the rear chain, etc. I defy anyone to ride a Velo, AJS, BSA single hard across the continent an have it stay dry. As for Royal Oilfields. . . But ok, it IS poss to have a dry bike, but you have to be very vigiliant.
Hi,
Yes, back in the day when BSAs were daily and family transport they were more likely to have a leak as the they were kept on the road by owners who needed to do quick repairs over the weekend ready for Monday morning and despite their best efforts bits of damage would occur as many of them would have been reluctant mechanics.
Today with the luxury of better sealing materials and time to get things right it is possible to get an oil tight BSA without spending a fortune. It is more about attention and care when assembling and then riding hard, within the design capabilities of the bike ,and long, within the design capabilities of the rider backside, is not a problem.
Even high mileage bikes an be oil tight.
Dave.
Aye, guess that's right. When i've got the M21 back on rd, i'll let you know. Cheers.
Personally, I don't think there's any excuse for an oil leak on an old bike anymore than a modern one. I agree that the bikes had chain lubes and breathers but they're not what I'd call oil leaks as it's intentional.
In 1972 I had an almost new A65 and it never leaked a drip.
Three years ago I bought a 1970 T120R and cured all the oil leaks on it. It still doesn't leak.
Last year I bought a T160 Trident and that is nearly leak free now - haven't finished yet.
This year I bought my C15 and have cured several oil leaks. She's nearly back together so look forward to continuing the quest.
These are all very useful posts. They tell me that if my bike has a leak, well, it's not unusual (as Tom Jones might say) and there's no reason to feel down about it. But they also tell me that these leaks are not incurable, and that I could have a machine that doesn't drip oil. I'd love that. Phil
In reality, things should only leak for a reason.
One is wear generating more clearance, another is faces that aren't flat either due to distortion, burrs or debris.
Incorrect assembly is another, bad gasket, poor jointing if required. Faces should be lapped flat and or stoned. Careful prep is essential.
I've found small weeps after a decent run and on one occasion it was down to slightly too much oil which when thinned with heat and aerated sneaked out of the oil seal. I bought a new seal to eliminate it but eventually found - by using the level plug, it was a touch overfilled.
There are others but with care can be identified and eliminated but only if it bothers you. The main thing is to enjoy your ride or tinkering if you can't.
Hello everyone. Here is an update.(now come on, there's no need to groan.) Went for a ride this morning with an emptied pc. Just a couple of miles. The photo was taken when I got home. No dribble apparent, but a bit of oil on the bottom of the pc. So, I'm thinking the leak is probably coming from the pc. Obviously, nagging uncertainty remains, esp given that some experts on this forum have fancied it might be coming from the gearbox. Anyway, I think I'll have another look under the clutch.
I've made a little list of what I should buy:
- pc gasket
- circular cover plate gasket
- clutch oil seal
- gearbox sprocket oil seal??
- felt washer
- alternator rotor tab washer
- clutch tab washer
- alternator wires grommets
- chaincase plug screw with baffled breather
Is this right? Have I missed anything? All comments much appreciated as always. I always find them very useful and very interesting. Phil
Just put 1/4 pint of oil in the pc, and went for a ride - same distance. When I got home, had a look: a slight leak, but not much atall. In a way I'd have preferred more, as it would have helped the diagnosis. I still think it's from the pc, but also that having had too much oil in the pac at one point might have made it significantly worse at that time. So anyway, as I said on my previous post, I'll take the clutch etc off and have a look. But I guess it's not urgent, esp as the leak is not exactly rampant. Phil.
No groans from me Phil. I enjoy following your posts especially as you're enthusiastic and keen to learn plus I often learn something from the advice from others.
Before you embark on your project, it could well have been too much oil initially and you were encountering the consequences. I know you've added 1/4 pint but that aside, did you use the level screwa and let it bleed from there? IMO it's a better way to sort your level than dispensing a set amount.
If you have too much oil you will probably see what you did before and strip the clutch when it wasn't the culprit.
Your list looked pretty comprehensive but if your bush has a split in it or is loose on its shaft it will leak and counter all your stirling work. If the bush is plain on the diameter and there is a groove worn by the oil seal, unless its symetrical, reverse end for end so it tracks on a different position.
As always, good luck
The bike has been stood unused for 2-3 days, on its sidestand. Out of interest, I had a peep underneath just now. The wall on which we've seen the dribbles was pretty much dry. If the leak there was from the pc, then I guess that's what we'd expect.
But also visible - see photo - is a drip of oil with what I think is the colour of the dye I added to the gearbox. The drip tray underneath is pretty much dry. If there have been any drips into then they've spread out and are now just part of the general oily film coating the bottom of the tray. So it looks like, literally, a drip or two over a couple of days from a stationary gearbox. So not too bad. But I guess there might be more if the gearbox were running (moving parts, warmer so thinner oil.)
Could you tell me please: where the drip of orangey-coloured oil is showing, whereabouts on the gearbox would you say that is coming from? It's hard to tell where the drip is coming from because, running my finger around the surfaces, they feel dry.
Phil.
You should just be able to see the layshaft bush as a bronze disc between the mainshaft (connected to the gearbox sprocket) and the bottom of the gearbox. This sits below the oil level tube and if its not a good seal with the casing, you'll get the odd dribble here, particularly after a run. Its easy to replace or seal, but unfortunately you can only get at it from inside the gearbox.
Have a really good look underneath to the right of the lower chain under the sprocket. If there's oil between the sprocket and layshaft bush, the problem lies with the mainshaft oilseal.
Hi Phil
Additional to my last post, check whether the hole in the gearbox filler cap is clear to stop any pressure build up in the gearbox.
Just had a roll round on the garage floor, can't see a bronze bush, but the bike's on its sidestand which I imagine might make it impossible to see. I'll heave it onto its centre stand tomorrow and have another look.
Quote from: Greenfield on 21 Jul, 2020, 15:19
Hi Phil
Additional to my last post, check whether the hole in the gearbox filler cap is clear to stop any pressure build up in the gearbox.
Yes the hole is clear, thanks.
Hi Phil
Pic 1 taken through the sprocket window behind the clutch, shows the layshaft bush just below the bottom teeth of the gearbox sprocket. Its a bit dark I'm afraid.
Pic 2 is taken with the gearbox empty, the bush is central and the oil level tube is at about 5 o clock.
Quote from: Greenfield on 21 Jul, 2020, 15:11
You should just be able to see the layshaft bush as a bronze disc between the mainshaft (connected to the gearbox sprocket) and the bottom of the gearbox. This sits below the oil level tube and if its not a good seal with the casing, you'll get the odd dribble here, particularly after a run. Its easy to replace or seal, but unfortunately you can only get at it from inside the gearbox.
Have a really good look underneath to the right of the lower chain under the sprocket. If there's oil between the sprocket and layshaft bush, the problem lies with the mainshaft oilseal.
Thanks for this. I guess I can only see the bronze layshaft bush when I've got the clutch off? Phil
From the right side of the bike if you feel around the back of the gearbox where there's a rounded bump on the bottom (this houses the layshaft gears), when your finger tips touch the chain coming round the bottom of the gearbox sprocket, the flats of your finger tips will be against the layshaft bush.
Sounds a bit complicated but should be straightforward. For a better view, the bike needs to lean to the right, ie not on the propstand, and look from the primary side.
Sorry to correct you, but what you feel on the outside is a cap that seals the hole in which the layshaft bush fits - you can't feel the bush itself. In principle, it could leak oil but this is only likely if someone has inadvertently disturbed the cap at some point - for example, while trying to get the old bush out.
I've been struggling to put arrows on my photo.
Placing my camera where I can't get my head, I think I now have a photo of it. I think the cast boss (top arrow, if I've managed to put an arrow there) is where the cap and bush will be, though they aren't visible from this angle?
I'm not sure what the other bit (bottom arrow, with any luck) is.
Phil.
Sorry to hijack your post Phil but I've just taken another photo of the layshaft bush/cap through the gearbox sprocket cover. What I take to be the bronze bush is centre photo below and behind the chain. AWJDThumper is saying that this is a cap. I can't see evidence of a hammer and screwdriver botch and I'm pretty sure that this is the back of the bush. Can someone clarify this?
Looks like a closed-end bush?
Unless the hole is stepped (counterbored) and it's a cap?
Phil
Hello everyone, To remind you, it's a 1965 B40F. Having fitted my NOS clutch cable, I went for a quick run out this morning, just a couple of miles. The clutch seemed okay. When I got back, I put the bike on its sidestand and had a peep underneath to see what was happening regarding any oil leaking. The photo shows what I saw.
I think (my colour vision is very poor, but I got my wife to have a look also) the oil you can see has an orange hue about it, which tells me it's come from the gearbox (where I put the dye.) The vertical surface beneath the layshaft bush is not visible, but I ran my finger along that surface about 15 mins after parking up, and it felt dry, but I guess any oil, being warm, might simply have run off it by then (should have checked sooner.) But as the bike is on its sidestand wouldn't oil still be coming from there if that was the source of the leak?
You'll see a large drip of oil hanging in the foreground of the pic, so quite a way from the bush, and also on the horizontal surface, along the line of what I think is a casting seam. It is also on the horizontal surface out of sight in the foreground. The vertical surface (facing us) where I had the dribbles before felt a bit oily, that's all. As you can see, the drain plug looks fairly dry.
I know we've discussed this before, but can I just recap, and check where the gearbox oil could be coming from (yes, I know, the gearbox.) Am I right in saying it must be from one or more of the following?:
- the seal behind the clutch;
- the layshaft bush;
- the drain plug.
Any other possibilities?
Thanks as always, Phil.
Maybe a porous casting. I know it happens on engines maybe it can happen on gearboxes. Or could it be a crack that opens up when hot.
If you have a wprn shaft that won't let the seal remain oil tight you can get a repair sleeve. I have used these and found them reasy to install and effective
https://simplybearings.co.uk/shop/Products-Speedi-Sleeves/c4747_5335/index.html
Okay thanks very much Dean, that's worth keeping in mind.
I've just been for another spin down the road, and this time felt the vertical surface under the layshaft bush as soon as I parked up. There was oil on it. But there was on the other surfaces around there too.
Anyway, re my post earlier today, any thoughts anyone on possible sources of the leak(s)?
Phil
Well, time has passed, and my search for the source of s slight leak has been unsuccessful again. I've had the clutch out, replaced the seals, renewed the circular plate gasket, also the alternator wire grommet (and incidentally done loads of other stuff which I came across) but the dribble remains (see photo.) I'm annoyed with myself for not checking to see if the bush on the main shaft is split or not (I was so distracted with other things I found that needed doing.) Can't see a split on the photo but guess it could be out of sight. Anyway, re the dribbles, ideas welcome as always. I'm pretty sure it's chaincase oil not gearbox oil (I have a very slight gearbox oil leak also and that's a different colour.). Phil
Re the above, I can see I'm going to have to take the clutch out again to check if the bush is split longitudinally or not. Sigh. Maybe come the autumn/winter. I wonder, could oil leak out of the chaincase by tracking along the threads of the countersunk screws which hold the circular cover plate? They are done up nice and tight, but do you think oil could nevertheless escape that way? Clutching at straws here maybe. Phil