Tappets and rule of nine...

[Arthurdaily]

Okay, so to set tappets on a morris, with a firing order of 1342, you move the engine round till number 1 is fully down, then set valve 8, and so on and so forth - simple. But does this method work on ALL 4 cylinder petrol cars?

I have fiesta at the moment with an engine that fires 1243, could I still set the valve clearances in the same way? In the Fiesta manual it says to set them when the rockers are 'rocking' in pairs... so not when fully down, i.e not the rule of nine... but can I USE the rule of 9?

Any help appreciated!

[bmcecosse]

1 and 2 and 4 and 3 are still opposed....so yes. But you must use a King Dick spanner on the lock nuts........... They are of course not 'tappets' - just rockers......

[IslipMinor]

The rule of 9 works on any 4 cylinder engine which has a symmetrical valve layout, like the A-Series, i.e. EIIEEIIE, or a variant on it. Rootes in the 60's and 70's, at least on at their aluminium headed engines, used a slightly different layout, but still symmetrical EIEIIEIE, so it still works.

I don't know the valve layout of the Fiesta engine, but from looking at a manifold gasket set on eBay, it may be either EIEIEIEI or IEIEIEIE, in which case the rule of 9 does not work.

[Arthurdaily]

King Dick? Humour or a serious point?

[bmcecosse]

Very best of spanners......