Gold flash bad oil leak

[Captain Mike]

Hi all
I have a bad oil leak between the primary drive cover and the engine sprocket, I cleaned everything off to see where it is coming from and it is not coming from the seal between the outer primary drive case and inner, it is coming from behind the primary drive cover, I am thinking it is the crank oil seal

Do people concur or could it be something else, and if it is the crank oil seal what is the procedure to fit a new one

Thanks

Mike

[Jackson]

I don't think a failed crank oil seal on a plunger can leak to the outside world. It should leak into the primary chain case. It should be a solid casting behind the cover. Are you sure it's not either the chain case drain screw (lowest cover screw) or the level screw? They leak badly if the small fibre washers are missing. I put gasket sealant on them as well to be safe.
Adrian.

[Captain Mike]

Thanks Jackson
I will clean everything off again and try to see where it is coming from however it is difficult to see

Hope you are correct

Thanks
Mike 

[DAVE BRADY]

Hi Mike,

How are you getting on with finding the leak?   The plunger primary can only leak either from the drain/level screws as mentioned by Adrian or the joint face between on the primary cover.  The joint face is quite narrow so a leak is not surprising but it is possible that a dribble from the engine breather could run down and drip off the bottom  of the primary case.  Ditto a leaky seal behind the clutch or the gear box.
After wiping off any oil does it leak when just standing, on side stand, on main stand or only after being run?
I suppose the other thing to try and determine is if it is engine, primary or gearbox oil.  Engine oil is more likely to be contaminated and be 'dirty' looking, gearbox oil probably quite clean and thicker, primary oil should be relatively clean and thinner than either of the others.

Dave.

[Jackson]

Mike,
I really hope it is travelling from somewhere else or the screws.
If it really is behind the chaincase, it will be expensive.
Good point about engine breather though from Dave. It could easily be running down from there. Also, the story is that they expel oil from the breather if they have wet sumped. I stopped mine doing it by fitting a SRM oil pump.
Adrian

[Captain Mike]

Thanks for the info guys

The oil is dirty and a lot of it, only leaks when running, I will investigate the breather first and hope its not the gearbox although the oil is black not clean

I have a Austin seven in the way at the moment so can't get to the bike easily but will clean everything down and start her up again to see if I can see it

Thanks

Mike

[RESTORER]

Hi Mike, Just to back up the others, when I recently ran my '54 Flash having had the chaincase off for a few weeks for other problems, I had a build up in the sump and this was blown out off the breather pipe, so much that I could not tell where from - what a mess. After cleaning down, finding nothing and looking in the oil tank, it became obvious. Yours sound just like it. Hope so.

[Captain Mike]

Thanks for all the help I will check out the wet sumping issues as soon as I can and report back
Thanks
Mike

[Captain Mike]

Looked at the oil level in the tank, whoa !  Hardly anything in there! so definitely wet sumping, breather comes out below the tool box but doesn't  look like it hasn't been leaking though ?
I will drain the oil out and refill the tank and start her up again hopefully it may cure it

Mike

[Jackson]

Sounds promising. Good luck.
Adrian.

[DAVE BRADY]

Hi Mike,

The breather being referred to is part of the crankcase and exits just behind the primary case and crank case.
There is often a pipe fitted and I think this was standard on the plunger.  You may be able to feel it or you will have to try to look under the engine.
107 is the pipe, 105/5/6 is the clip and nut and bolt to hold it.

Dave.

[Captain Mike]

Thanks Dave

All is not lost ! this is obviously the issue, thanks very much for pointing this out much appreciated

looking at replacing the oil pump at the moment to reduce wet sumping issues, was going to fit the SRM one but there are none out there, does anybody know when these will become available again? 

[DAVE BRADY]

Hi Mike,

Best to contact SRM direct as they seem to be out of stock for all pumps.

Dave.

[Jackson]

When I wanted one they were out of stock, so I got in touch, turned out they were making them the next week. It took a fortnight all told because they test them before sending them out.definitely worth getting in touch.

[Captain Mike]

Hi All contacted SRM, and was told there will be some available in a couple of weeks, but then got an email to say they had one available right away if I wanted it, so I have purchased it, will be fitting it later this week, hope this will stop the wet sumping issue

The one in currently on the bike was leaking badly inside the primary cover the last time I looked so hopefully the new one will be a cure for that also


Mike