Hitchcocks Forum

Many of you have been helpful with this orphan
'49/'50 twin rebuild from a pile of misc distributor
carby and cam issues wel and good, but oil cascading
from c/shaft on the drive side. These very early
c/cases have a stud that holdst the primary chain case
on, and on removal of that the oil flowed our from
above the c/shaft's spline. Although the oil return
was evident in meagre amouts at the filler cap, now
suspect one may have been too zealous in fabricating
the sump's pick up gauze. Colin had mentioned the
early sand cast c/csse's close proximity of the
drain plug and oil scavenge pick up. and had resolved
that. These early c/cases use a 6" filter whose case
is cast in the sump. Whole issue is like my heart
surgery long ago, may have to go in there regardless,
and rebuild again with a set of later c/cases I have
which are a tad lesss flawed in oil distribution, Just
seeking one last silver bullet advice before dismantling
Thanxs, lads

Gordon, what exactly is your question? Sorry, but I can't understand what the problem is from your description, apart from that you think it's wet sumping. REgards, Mark

Gordon, some years ago Craig Jolly had terrible problems with a wet sumping rebuilt early twin, after many hours of frustration he finally discovered that the head had come off one of the screen retaining screws and it had been able to get under the screen and had been sucked into the scavenge pick up hole. If it is wet sumping it can only be a scavenge pump problem somewhere

Mark, I rambled a tad there,Shell shock, you know!
Seriously, I should have empathized I had fabricated
my own gauze screen in the c/case bottom, and wonderded
that the mesh was too fine. Norm has just mentioned it
takes little to block the scavenger return hole. How I
learnt the c/shaft area was full of oil, aside from it
pissing out, is that the original primary case cover
stud is approx 1" longer than the later ones as it
screws right into the c/case so when it was taken out,
I found out how much oil was in there. Colin on the other
posting has claarified the early quirks lurking inside
the early cases.

Gordon, I'm assuming when you mention the primary case stud you are talking about the primary chain adjuster stud

Norm, this is the usual centre 3/8" stud w/
the acorn nut that holds the outer primary
chain case on. Except on the motor c/cases
I have, the stud is I" longer as it goes
thru both cases , and screws into the c/case
behind approx 7" east of the c/shaft. Hence,
when it is removed, the oil behind would flow
out like a radiator's overflow.

Gordon, that stud is into the oil tank so of course it will have oil behind it, this has nothing to do with wet sumping

Norm, you're utterly right..Geez, what a ****ing
idiot I am, already measured the unused c/cases
to drill and tap, although I seem to recall these
cases were improved with a extra 5/16 stud that
goes right thru in the very spot where the chain
case 3/8 stud previusly was. However, all the wet
sump issues are real enough!