Suspected timing shaft oil seal leak

[yellowfever]

So I decided to press on clean the oil leak up and remove the old seal. First bit a messy and boring job but got things reasonably clean with brake cleaner and elbow grease.

Removing old seal initially looked like it was going to be another time waster of a job. I had hoped it would be so knackered it would fairly easily spin, but no such luck. Using the trusty metal pics it didn’t move at all. I had hoped to be able to carefully dig into the seal (not too far given bearing close behind it…) with 90 degree hooked pic, missing the metal tension ring and then spin and pull the seal out.

Instead I found I was just laboriously flaking bits of hardened rubber seal off the surface The reason I couldn’t get deeper into the seal became apparent after a while - apart from the metal tension ring visible on the back of the new seal, there is also a completely rubber encapsulated metal face plate that was gradually exposed as rubber flaked off the surface with my failing attempts to spin it or pull it.

Cue some thinking about other options based on some online research I’d already done. Drilling and/or using self tapping screws as some had suggested/tried in similar situations did not sound appealing given the bearing is right behind, and even if I didn’t hit it there was the danger of bits of seal including metal getting lost behind the seal into the bearing. An engine out split cases job if that bearing needs replacing, so not something I want to risk.

From looking at the gradually revealed interior of the old seal and looking at the new seal it appeared the best bet to get past the metal plate and behind it so I could lever the seal out would be nearest the shaft where the seal lips were. Of course scratching the shaft is a risk and won’t help with sealing if I do. But anyway no going back given state of the now partly butchered old seal. Combined with the flaking off of some more rubber near the edge and centre this started to produce results. The pic worked great as I could keep the point away from the shaft and use the smooth pic shaft against the shaft for leverage. I soon got the seal spinning but it still took me ten minutes to manage to gradually work it out onto the shaft where I could finally remove it.

Still, by the standards of how this job has gone so far, it was a fairly easy win.

Photo shows removed seal with part of now well scratched up metal face plate exposed.



I’d heard these seals were originally blue (replacements are brown) but they turn black when they get old. Mine was certainly black, but sure enough the edge showed some original blue…



Judging by the black colour the brittleness of the flaky rubber and the signs of degrading seal lips before I removed it, it clearly was needing replacing. Whether it is confirmed as the culprit for the oil leak time will tell once it’s all back together…

[yellowfever]

Whilst on a roll I decided to go ahead and try to install the new seal. I used some electrical tape to patch over the crack in the installation cap tool and was reasonably happy this would allow the seal to pass over the thin tape OK with the tape doing enough to protect the seal lips from the sharp edge of the crack.

Fitting the cap brought a new problem. I’d intended to use an extra deep socket to push the seal on square and push it into the housing. I already knew that the socket was not quite deep enough, as the shaft was too wide to fit though the socket drive hole. But I hoped it would get the seal into the housing, even though it wouldn’t be fully seated. However with the extra length of the tapered cap installed over the shaft the socket now came up too short for the most difficult/important bit of getting the seal squarely into the seal housing.

After some head scratching looking for washers or other possible packing options I spotted an old metal torch that didn’t work any more. Some creative destruction later I had a nice metal tube of the right width and length to use as a drift. The edges were a bit thin so some creative bottle cap drilling produced a nice plastic rim. Sadly it would not sit straight despite some rubber malleting and then I couldn’t get the cap off to try again. So i left that end and used the magic of electrical tape on the other end…

Some industrial alcohol moistening the seal and with difficulty using the socket I got it onto the cap and slid down over the start of the electrical tape coving the crack. Thankfully the tape didn’t move even with the tight seal/alcohol. Then it was on to using the repurposed torch shaft drift. It was pretty tricky getting the seal started in the housing, I had to back off and moisten the outer edges with alcohol as couple of times. Eventually I got it square and in the housing, but getting it fully home was tough. In the end a rubber mallet tapping the end of the torch shaft a few times managed to get it fully home.

Tools of the trade… electrical tape repaired broken tool, socket drift, repurposed torch body drift, rubber mallet



At it’s in! Finally!



Time will tell if the various abuse getting the split ring and old seal out and the new one in over the bodged broken tool has compromised the sealing, but anyway at least I know it’s good and tight so should be OK, so fingers crossed…

So anyway I thought I’d crack on and get everything buttoned back up, the belts on and see if I’d got the leak sorted or not. Of course as things had just gone well inevitably it couldn’t last and I ran into a problem straight away. I refitted the split ring and immediately regretted it. The ring clearly had suffered too much in the marathon attempts to remove it so it was much looser than before in the groove. The spacer washer fits over it and contains it in its own groove so it might have been OK but I just didn’t want to risk it. So I’ll have to wait until I can get hold of a new split ring before I can put everything back together.

Naturally even loose it was a pita to get off again, but my special method managed it after 10 minutes of wrangling.

Cotter pins are your friend. Split rings are your enemy…



After that I rang the parts guys. Damaged cap tool will be replaced (I don’t even need to return it) but will take 2 weeks at least (glad I just went ahead and bodged it). I’ll return and get a refund on the too stiff fixed roller. I’ll have to pay return postage but they’ll refund me if they agree it’s defective when they get it.

And thankfully the split ring should be with me by the end of this week so hopefully I can get it buttoned up and tested by early next week…

[yellowfever]

After some light relief sorting some electrical accessories (see other thread) snap ring turned up today, so I hoped to get things back together and finally see if I’d sorted oil leak and could get back to some riding.

Sadly the snap ring had other ideas. Spent a very frustrating evening trying to get the damn thing on and the grooved washer fitted over it. Various tools, schemes and some home made tools later and I’m still stuck… if anyone has any magic ideas/tool suggestions I’m all ears… meanwhile here’s my tale of woe on how it went so far:

Workshop manual says you slide the snap ring over the special cap tool, then slide cap over shaft, then slide ring off tool into groove… So my bodge repaired broken cap tool was pressed into service again. Half an hour later the snap ring was on the tool. Lots of frustration trying to lever the snap ring on and the usual comedy moment when new snap ring I’d waited 4 days to get flew off the tool and I had to spend 10 mins searching the garage for it.

Next steps sliding tool onto shaft and snap ring off tool into groove on shaft were a breeze. Unfortunately the end result of this is a rather stretched snap ring that is no better than the old one, sitting quite loose in the groove. I took it off tightened it with pliers and put it back on without the special tool which made it snugger than using the tool but still not great. Clearly I’d have been better off ignoring workshop manual on using special tool for install. Inevitably it’s wider than the shaft so is a pita to get on and stretches the ring.

I then fitted the first woodruff key which went well using a clamp to install it.

That’s when the fun really started. The spacer washer slides over the shaft and woodruff key and a grooved face then goes over the snap ring so it is in the shaft groove and the groove in the spacer washer. This keeps the timing gears on the timing shaft and away from the cases. However I just can’t get the washer on over the snap ring. Access is very tricky behind washer very close to cases I’ve tried pics, Allen keys, jewellers screwdrivers, deep socket and hammer and a plethora of bodged home made tools including various adapted washers, bits of plastic, a brass measuring tool and other equally ineffective options.

Trying the old snap ring off the shaft I can fairly easily hand fit it into the spacer washer groove with a satisfying click, but this involves pressing one end in the then pressing and rolling the other side in with my thumb. A sort of inwards and forwards motion. Or course access makes this impossible in situ as there is only a mm or two between the washer face with the groove on and the engine case/seal boss. I’ve been trying to replicate the action with tools with the snap ring in the shaft but this has proved fruitless. I did wonder if putting the timing gears on and then torquing down the nut on the end of the shaft (I can reuse the old nut for this as they are single use and not cheap!) might push the washer down the shaft and force the snap ring into the washer groove. But similar approaches with a deep socket and pressure seem to just push the ring out of the shaft groove and towards the seal (maybe as it’s too loose…)

Anyway enough for now, will sleep on it and hope inspiration or better luck strikes soon.

Really had enough of snap rings!