Hi all
Can anyone tell me the proper width of the spacer that should be fitted on the offside of the central engine mount (the one under the engine) on a B40(&C15)?
TIA
B40 = 13.9mm / 9/16" based on my checking and the 14mm spacer on my 1965 B40
https://www.bsaownersclub.co.uk/bsaoc_forum/index.php?topic=20507.msg111455#msg111455
Not sure if C15 the same. RR I think cites 1/4".....which must be wrong ( If I'm allowed to say that without being struck by lightning)
Thanks for that.
I looked at RR and thought that it sounded a bit narrow!
Is there anything on the near side?
Well mine has no washer/spacer on the nearside, between engine and lug.
( note that, as in the thread I linked, I have a very close clearance below the outer timing case edge and frame below the kick- start....that seems too close. Parts catalogue doesn't show anything for the nearside of this fixing, just the spacer for the offside)
So the spacer could be more than 14mm?
I'll measure the gap on mine.
The frame rails had been bent inwards so I straightened them using the approved piece of threaded bar. It's possible l slightly over did it!
The gap on mine is nearer 3/4" plus there is a gap on the near side!
The engine cases do not look as if they've been 'modified'.
Would be nice to have a definitive on the spacer......or total width between lugs.
RR gives a spacing of 5.054"....... but shown slightly to the rear of the lugs...so not sure how useful it is.
I will endeavour to see if I can measure...but the pinch point on mine is so near the rear loop bracing....and distant from the lower engine mounting... I find it hard to see that undersized spacer is the cause of my issue...but I could be wrong
Hi,
As it is a spacer intended to fill a space perhaps fit the front and rear engine bolts. As far as I know the engine should be a snug fit so not have spacers/shims etc. Tighten up the engine bolts and now measure the gaps where the 'through' bolt goes. I suspect that there will be variation due to manufacturing tolerances so actual thickness required will vary a bit.
Dave.
Quote from: Stubaker58 on 27 Mar, 2025, 21:56 Hi all
Can anyone tell me the proper width of the spacer that should be fitted on the offside of the central engine mount (the one under the engine) on a B40(&C15)?
TIA
I've got a 1969 b40wd and there's no spacer on the central bolt under the engine.
The gap in the frame where the bolt goes through is 4 1/2" and so is the engine casting.
I've measured under the engine and the haps I've got are 8mm near side and 16mm off-side.
I've got to take the engine out again as the near side frame rail is kinked upwards slightly meaning the through bolt doesn't go through.
I'll photograph the frame then and may seek to pull in the lower rails if they are a long way over the 5.054" width shown on the RR frame diagram.
The front and rear mounts are fine.
The offside spacer is 41-4036.
Thanks
Measuring between the lower rails shows the gap as 51/2" on my frame.
The rails don't look bent.
RR suggests simply making up spacers to fill the gap. I can do that!