Tappets

[Hobbo]

Hi whilst I have the manifold off is there a cold setting for the tappets. Handbook says set whilst the engine is hot, don't fancy having hands under scorching hot manifold but if needs must so be it. Thanks Mike.

[Colin Wilks]

I was advised by a very experienced sevener to set all gaps to .010" cold. I have followed his advice and it seems to work. However, I have a feeling you may find this is a contentious issue on which opinions differ!

[Howard Wright]

Hi Mike

I’ve always set mine at “sixes and sevens” 6 inlet 7 exhaust but that is a standard Seven. I believe your car is a Big Seven so it may be different?

Cheers

Howard

[Jeff Taylor]

Hi Mike,

Pitman's 'The Book of the Austin Seven and Eight' fourth edition 1953 recommends the following tappet clearances for the BIG SEVEN and EIGHT. This clearance recommendation is contained within Chapter 5 'Decarbonizing' which describes work on an engine block minus its head, manifold etc so I assume these will be cold clearances:

0.008" to 0.009"

[Parazine]

I've used 0.006" for inlets and 0.008" for exhausts (cold) for the last forty years. Hasn't let me down yet and the valves don't burn out!

[Chris KC]

Likewise I use 6 in and 8 ex.

I would never, ever contemplate setting them hot - should always be done at room temperature except under the direst of circumstances.

[Alan]

Agreed. 6 and 8 cold.

[bystander]

Adjusting the clearance with a feeler gauge may be academic anyway. Often the tappet head has had an indent hammered into it by the valve stem over time, so the actual clearance may be greater - not that that is necessarily critical in normal road use unless excessively clattery.

[Bob Culver]

I note that LM Williams in his Specials book, immensely revered on this Forum, recommends .004 which I recall was the company recommendation. He does not distinguish various valve steels. Austin book 843/C 1957 states .004, hot!
I presume all cars are now running modern exh valve steels which expand more than XB and earlier, so somewaht greater gap appropriate.

[Chris KC]

An indented tappet head at least results in an error on the 'safe' side i.e. too much gap.
Tappet screws clean up quite nicely if you chuck them in a bench drill and bring the head down onto some oiled wet & dry paper - on a flat surface of course.