27 replies to this topic

[Spider]

How come the SA stuff is so different to UK stuff.
I thought it would of made sense to standardise all bits no matter where they were going to be used.

 

It was to do with local taxes in South Africa at the time (and still now) and if I recall, to get some Government Grants to do with local content as well as just what sort of content.

They took the opportunity to not only make their own engines, but as you can see, a redesign of them too. Personally, I think what they did here was smart and I was surprised in the late 70's when BL wasted 35 millions on coming up with the A+ in two versions, small and big bore with no real improvements between them, eg, the small bore retained tappet covers and there's next to no common parts between them.

[timmy850]

I remember reading the South African taxes were based off the amount of local content by weight, which is why the engine block was a good candidate for local production

Whereas I think the taxes in Australia were off component number and local assembly,, so the engine parts were imported from the UK and assembled locally

[nicklouse]

Right, had some time after the visitors to the garden left so the tools came out.

 

I would say I got to it too late. But things might polish up. Not measured anything yet. Only one thing surprised me.

stripped everything of the “front” and back then the head off.

 

timing chain was well worn.

cam was spider drive but no makings on it at all.

never seen a spider drive crack.

pistons as Timmy mentioned

bearings. Seen worse.

crank nose was in fair condition until the rust.

and that is we’re there might be issues. 
 

needs looking at and see if things will clean up.

 

spotted the item that surprised me?

 

 

 

 

 

 

 

[KTS]

Shells in the mains caps are wrong

[Spider]

It actually seems in good condition for the most part.

 

Was it the Duplex TC set that was a surprise ?   They were factory fitted to all 1275's at least to 71.

 

I think the tail on the Crank will clean up better than you might first think, it'll need material off it, but definitely won't be the end of the world. Just size up the Primary Gear Bushes to suit.

[nicklouse]

It actually seems in good condition for the most part.

 

Was it the Duplex TC set that was a surprise ?   They were factory fitted to all 1275's at least to 71.

 

I think the tail on the Crank will clean up better than you might first think, it'll need material off it, but definitely won't be the end of the world. Just size up the Primary Gear Bushes to suit.

Almost. It was the oil throw washer on the timing gear. A proper shape that does not need a F to show how it should be fitted.

[Lplus]

Shells in the mains caps are wrong

The shells in the main caps look correct.  It wasn't until the 1275 A+ blocks were established that the main cap shells were changed to solid and used a centre locating tag.  I have examples of both.

[nicklouse]

Well a bit more cleaning and measuring.

 

head is 2 3/4” thick.

 

block 8 7/8”

 

Bearings on a 10 thou grind. Mains

the block is fully linered.

 

The 11th stud. I think is original. And does not break through to the water pump cavity.

bore measures about 70mm 

 

crank is not quite as bad a I thought. But will be taking it to a machine shop for some work.

 

mmmm I have a S head on the shelf. Just no Mini to put it in. Yet.

[timmy850]

That engine looks pretty good all stripped down, especially compared to some of the boat anchors I stripped for parts.

The big dilemma is how to make up the deck height of the reduced stroke…

The most common way on Mk1-forum was to deck approx 1/4” off the block. The second way is to use 6” conrods with std height pistons

[Spider]

 

Shells in the mains caps are wrong

The shells in the main caps look correct.  It wasn't until the 1275 A+ blocks were established that the main cap shells were changed to solid and used a centre locating tag.  I have examples of both.

 

 

It was actually around 1984 when they changed the shell types. The early A+ used the Shells with the Oil Groove in both sides,

[miniGTS]

The big bore SA 1100 also had the twin valve springs on a 12G940 head with standard size valves. 

 

I have one of those engines as well but it's had a fair amount of work done. Lightened, balanced and gas flowed and ported head. I'm planning to use that engine in my GTS project.

 

I have a spare 1100 crank that I'd sell but I'm in SA. I also think it was machined, possibly balanced so not sure what that means as I was told the crank and piston assembly should be balanced as a unit?

[timmy850]

You can definitely balance the crank on it's own. You can also balance the clutch and flywheel separately and that should make a balanced rotating assembly.

 

It is common to balance the crank, clutch and flywheel together. 

[nicklouse]

Just been back to look at the timing cover as it might be useful for a poster and I noticed some things.

 

I don’t think the thrower was original. 
you can see where it was rubbing. And had worn a sharp edge on the thrower itself.

Also looks like it has run with a worn chain at some time?

some general condition pics.

 

has been moved without gearbox which has cracked the cover on the return.