And then it went Bang

[Tony Betts]

Hi R,

It could be down to the age old problem of a little knowledge being dangerous.

People read about high lift cams, and double valve springs. Then thinking they have been armed with the meaning of life. They fit it to anything they touch.

Not having enough knowledge to know they are doing more harm than good for there particular use.

The only reason I can think of useing maxi springs, are the tight arses who buy an unused set of old springs for a £1 thinking they've saved themselves £4.00

Again, a little knowledge.

It does make me laugh every time I pull these things out of engines though.

I'll send you some pics of the last slip cotter I removed.

Tony.

[Zetomagneto]

Fatigue failure of the block, has it been dropped during it long life,does anyone crack test these.
Would be interesting to see the top face of the crankcase

[Ian Williams]

---

Pistons are 57.5mm. It's a mid 30's block. It looked thin to me as well.
There weren't extra studs in the valve chest - it's just broken across there.


Charles

Hi Charles,

May be good to try get a vintage block, I understand the material is closer to chromidium.

Would hopefully be stronger.

What are the two drill holes between 1&2 and 1&4 that's were I thought you might have put extra studs.

Tony.

Tony I have seen these two drill holes in late blocks and crankcases, I always assumed they were there to increase the old mist in the valve chest.

---

Dave, I was suggesting using SAE Grade 8 bolts which are an much higher tensile than metric grade 8.8

[Ruairidh Dunford]

Ian/Tony,

a friend has mesaged to say the extra holes were used in late (three bearing perhaps?) blocks - I had not noticed this before.

Can anyone confirm?

[Tony Betts]

I can't remember seeing them before. That's why I thought they had been put in.

I'll have a look in the morning.

Tony.

[Charles P]

I can't remember seeing them before. That's why I thought they had been put in.

I'll have a look in the morning.

Tony.

I couldn't remember seeing those bloody holes before either. Wish that I had!
I'll check the block casting date but I think that's it came from a 33/34 engine

The new block is vintage for all the reasons that have been said

Charles

[Ian Williams]

I can't remember seeing them before. That's why I thought they had been put in.

I'll have a look in the morning.

Tony.

I couldn't remember seeing those bloody holes before either. Wish that I had!
I'll check the block casting date but I think that's it came from a 33/34 engine

The new block is vintage for all the reasons that have been said

Charles

Three bearing is where I have seen them guys.

[Ian Dunford]

Oops!

Have you considered "Holts Crank and Bloc Weld"?

[Ian Williams]

I have in the workshop at the moment a January 37 block without them and a July 37 block with the holes, I probably have a few more in my spares shed.

[Tony Betts]

Charles,
Your block looks to be pre three bearing engine.

The ones for three bearing engines, have an extra piece on the centre stud hole. Water manifold side.

Tony.