Hitchcocks Forum

hi Guys

I've a 1959 big head bullet which has developed a leak from behind clutch and when engine is running the oil in the primary chaincase leaks out and runs down the back of the chaincase, infront of the gearbox sprocket and down the centre stand. Been looking at our hosts online parts books but there is no oil seal pictured. Should there be an oil seal? if so does any one know the part number so I can order one. If there isnt then how would I stop the leak?

Many thanks

Bandit

Bandit, yes, there should be a seal. By 1959 I think it was a neoprene seal and the part number should be 43565. However, I'm not sure if the BH was still being fitted with the earlier felt seal at this point as 1959 is round about the changeover year. I'd ask our Hosts but also bear in mind your case might have been changed in the past so I'd check what you actually have first!

REgards, Mark

Hi Bandit, Are you certain the oil is leaking from the chaincase and not the gearbox? The reason I ask is that my 1960 Clipper has the same problem you describe with oil dripping onto the centre stand when the engine is running. I recently installed sealed bearings in my gearbox so that I could use oil instead of grease in it. Before putting in the sealed bearings, globs of grease were forming on the floor and the centre stand so it was obvious the leak was coming from the gearbox and not the chaincase. I might now revert to using grease in the hope the gearbox will stop leaking. I've run the engine a few times since putting in the sealed bearings and while the oil level has gone down in the gearbox it doesn't seem to have reduced in the chaincase. I'm sure if the seal is missing or damaged in your chaincase there will be a leak from it but I thought you might be interested in the situation I'm having.

Bandit, my October 59 Bighead has the oil seal, but my April 59 Bighead parts book has the the felt washer behind the metal plate.

1959 - felt washer 32383, 1960 - oil seal 45006. As Mark says, see what you have.

Thanks for the replies guys.

I have just taken the clutch off and exposed the seal, Yup defo a felt jobbie so rang our hosts and they do a neoprene upgrade with gasket so placed an order and its on its way.
Re the clipper oil leak, yes I did consider this as my gearbox is full of that black grease our hosts sell with a bit of oil thrown in for good measure. I'm sure my leak is from the primary chaincase because the clutch would stop working properly making it very difficult to change gear and find neutral and chaincase would need regular refills.
Sorry to hear you are having oil leakage issues on your clipper but would thoroughly recommend filling your gearbox with the special grease our hosts sell.
I'll keep you updated with progress when I refit everything in a few days.

Bandit