One for the BMC 1.5 experts.

[GBW]

What's this?  I can't find a location for it.  The length is 50mm (nominal 2").  None of my manuals shows it.  (Could be off something else and infiltrated the rebuild bench 🤫).

[BWM]

Not familiar with this engine but it looks like a lift pump spacer.

 

[Tracy D'arth]

2 minutes ago, BWM said:

Not familiar with this engine but it looks like a lift pump spacer.

 

Agreed it does, but not on a BMC 1.5D.  Studs are horizontal not staggered on the BMCs.  And why the tail piece?

Familiar but eluding me.

[GBW]

The three circular holes exactly match those on the chain tensioner but the slot has me baffled.

[Tracy D'arth]

16 minutes ago, GBW said:

The three circular holes exactly match those on the chain tensioner but the slot has me baffled.

You are correct!  Its the shim plate from behind the tensioner, the bolts go through the holes.

[GBW]

And the slot?

[Tracy D'arth]

I think that there may be an oil feed in the slot on the block. It serves no other purpose as far as I remember. The rubber faced tensioner block rides on the tail section of the shim.

[bizzard]

34 minutes ago, Tracy D'arth said:

I think that there may be an oil feed in the slot on the block. It serves no other purpose as far as I remember. The rubber faced tensioner block rides on the tail section of the shim.

There is an oil pressure feed to that hole, to keep the shoe in proper contact with the chain. The light compression spring is only there to actuate a new tensioner shoe with an Allen key and to keep the shoe in contact with the chain when the engine is stopped and the oil pressure drops to zero.

Edited April 17, 2023 by bizzard

[GBW]

There is no matching slot on the gasket.  The oil feed is through the circular boss.

The slot appears to be redundant.

[Tracy D'arth]

Oilway blanking plug in there?  I think the slot is unimportant.  Same part used on a different engine or did BMC need a bit of steel that shape elsewhere?