Well it WAS going well...

[Tael]

Hello again. Got the bike MoT'd tues, insured weds, taxed thurs and on the road for the first time since 1985 thismorning.

Work is only 1 mile away so leisurely little journey there this morning, especially as the front brake will need some bedding in (new pads and 26yrs of rust on disk) but all ok.

Warmed her up properly after finishing at lunch to see if she will tick over off choke ok (eventually yes), then decided to put some gentle miles on it this afternoon in the sun.
Called in at a friends house a couple of miles away to show her off when i noticed a growing oil puddle underneath. Rode even more gently (in 4th or 5th at 30mph) back home again - damn lucky I had stopped at his rather than the long journey I had planned.

Got back ok and started to investigate. It appeared to be from RHS of engine, off with rh cover and it would appear to be coming out of my crank seal behind the cambelt pulley/generator.

Bugger.

Now how difficult a job of replacement is this? from the manuals i have it isnt clear if the seals go in from the outside or inside....
Will I also have to consider the oil relief valve needing investigation?

Again, bugger, as once warmed up the initial feelings of riding it were starting to fulfill my 25 year odd wait to own one


as you can see the oil is around/below the crankseal


overall views of the 'finished' article

[Tael]

Well just been interrogating the owners club parts list, and the exploded diagrams, and as i feared the crank oil seals are a complete cases apart job.

'swear words'

[jb666]

I recall in the dim and distant past (I've had my Strada almost 30 years now) I remember replacing that seal in situ by careful use of small allen keys to get behind the seal. Getting it out is the tricky bit. As long as you are careful with the featheredge on the replacement seal you should be OK.

John.

[George 350]

Hi Tael,
You don't need to strip the engine. Remove flywheel, stator, belt, belt pulley and belt guide from crank, then carefully drill 2x 2mm holes in the front face of the seal - the closer to the outer edge the better- and screw in a self tapping screw. Then with a pair of pliers, grip the screw and the seal will usually just pull out.
For reassembly, professionals would use a seal driver, which is a piece of tube the same size as the seal that has a thin lip on the end that the seal lip sits on and moves it out of the way of the shaft the lip has to go over. If you or a mate have a lathe these are quick and easy to turn up. Then fit seal onto seal driver, drift home and rebuild.
If this is not possible, find yourself a large box spanner that is just larger than the seal at the corners, but the 'flats' of the box spanner will press on the front face of the seal.
Oil the crankshaft nose where the seal runs and fit the seal up to the crank/crankcase. You should be able to get the seal lip onto the crank without too much effort, just keep an eye on the lip to make sure that it doesn't fold over. If it starts to do this, then get some thin plastic (e.g. a yogurt pot)and cut a strip of plastic that will wrap around the crank one turn. Put this inside the seal, and when you fit it, the plastic can go over the crank and guide the lip in place. Finally, with a hide mallet, drift the seal home using the box spanner until the spanner hits the crankcase all around the seal housing. Remove plastic carefully.
Rebuild the rest and away you go.

Good Luck.
George.

[Tael]

Thanks guys thats cheered me up again. just been on phone to NLM and ordered a new seal (got the cam seal while i'm at it as it seems silly to do one and not the other while its apart)

As I didnt disturb the engine at all when i 'refreshed' the bike (it appeared to have been rebuilt at some time in the dim and distant past when i got it) I take it that investigating and checking the oil overpressure valve in the lhs engine case is in order?

[George 350]

I'm sure that oil pressure is not your issue. Between the main bearing and the oil seal is a cavity with drainage slots at the bottom to let the oil drain away from the bearing. The seal shouldn't be subject to any abnormal oil pressure, or even pools of oil. Mine did do a timing side oil seal (thats how I know you can fix it from outside) some time in the past, but I put that down to it's age. Your leak is more than likely due to the oil seal being old and hardened with age. Add in that having been stood, it was most probably dry when you first started it (as any oil would have long since drained away) which won't have helped as it will flatten the lip of the seal.
For what it's worth, mine had a crank regrind at 70,000ish miles when I did the big rebuild, and when the engine was apart recently for resurrection 2 (92,000 miles)the bearings were all fine and went back in. On each rebuild all I did was to wash the pressure relief valve out. It is such a simple device (ball and spring) that it can't really 'jam closed'. Unless you think that your big-ends or main bearing have worn out then 'if it isn't broken, don't fix it'.

George.

[EVguru]

Do check for play in the timing side main.

Also, make sure you don't have too much oil. Correct fill is 2.5 litres.

[Daddy Dom]

Also, make sure you don't have too much oil. Correct fill is 2.5 litres.

While we're on the subject, Paul, does that 2.5l go for an 80s Sport too (or indeed, all 350s)?
Cheers,
Dom

[George 350]

Paul,
Interesting comment that -"correct fill is 2.5L". Where did that come from? I know early bikes were 2.5L, but I understood all plain bearing bikes were 3L. I know that the owners handbook I got with mine was overstamped with a large red 3 over the 2.5 at that page, and that later dipsticks were marked higher up as well. Or do you mean minimum fill 2.5L?
Regards,
George.

[3potjohn]

2.5L semi synthetic in my 1982 350 does the trick.I just measure and mark the level on a plastic milk container.But you will see 3L quoted widely.Never seems to use much either.

[EVguru]

Paul,
Interesting comment that -"correct fill is 2.5L". Where did that come from?

I can't find where I've put my late factory engine manual, but I do have the Excalibur handbook within reach.

2.5 Litres of Agip SINT 2000 (10w40 semi synth) for both 350 and 501 engines.

3 Litres would put the oil level too high for the clutch seal.

Min and Max marks are just that, the minimum and maxumim safe fill levels. Normal oil level is between the marks.