Primary Oil - Page 3

tnsen · #21 (**permalink**) 02-15-2008

Originally Posted by Mecchanica

Right, NONE of the Triumphs vented into the primary until 1970. Not my 63, my 69 Bonnie, my 68 Bonniger (Tigerville). None of em. As far as I'm concerned, it was a bad idea to merge the primary and the engine lubrication systems. In fact, if you have the 70 on, I advise you to go back to the old system.

so i got a 71 bonnie..oil in frame...just how do you go back to the old system??.....tom

GrandPaulZ · #22 (**permalink**) 02-15-2008

You have to plug up the little oilways just behind the crankshaft sprocket, and install a seal on the crank.

There may be more to it, though...

bendavanza · #23 (**permalink**) 03-12-2008

If you were to block the 3 small holes (patent plate fasteners work perfect) and put in a seal, your crankcase is going to have to vent somewhere.
Some people will use the timing hole behind the cylinder, using an alternator wire tube from the primary (same thread). That can be messy, it's in the windage of the crank. Some will fit a tube onto the timing cover, less messy but more obvious. I did mine through the "nose" of the crankcase, using that cavity as a baffle. It works great.
Earlier models (pre 68) used a timed breather ran off of the intake cam.
-Ben

Woolly · #24 (**permalink**) 04-07-2008

I've got a '73 (or '74) T140V (engine/frame no NJ59372 (I'd love to find out when it was born (during the time of the lock-in I think))), which I've fitted with a 'Mad'? Australian belt drive - I've never put oil in the primary case (I do have the 3 holes in the crank case) - the clutch runs as a multi-plate Dry clutch and I've never had a problem with it.

GrandPaulZ · #25 (**permalink**) 04-08-2008

You likely have a seal fitten on the crank.

What breather setup are you using?

Are you experiencing significant oil weepage at some gasket joints?

Woolly · #26 (**permalink**) 04-08-2008

Originally Posted by GrandPaulZ

You likely have a seal fitten on the crank.

What breather setup are you using?

Are you experiencing significant oil weepage at some gasket joints?

When I rebuilt the bottom end, I put a non-sealed drive side crank bearing in, and use the standard breather system out of the top rear of the primary case. It still amazes me at how little oil gathers in the primary case - I figure the scavenge side of the oil pump is working (too?) well

- also no oil leaks - I can't use the old 'when it stops dripping, it's run out' sign anymore. To be fair, I spent about 4 months rebuilding the engine (on and off), Merriden used to knock out a few hundred(?) per day - I could spent a bit of time on mine obviating leaks etc..