1930 Model 22 valve stem clearance?

I've also just had a look in Franks' book and it looks like the top end of the engine was lubricated by 1932 so these clearances may well be different.

Previously michael_rettie wrote:

I'm trying to figure how much stem clearance to give this old beast. I have made new iron guides and am using Manley chrome stem valves that are the best quality I can find. I have no experience setting up this arrangement in an unlubricated environment and figure someone out there will know more than me. When I took it apart, it was reported to be running well with .100" stem clearance. Yes, 1/10th of an inch.

Thanks,

Mike

Mike, I've just had my head professionally done on my '27 M18 engine.

Valve clearances in guides were0.07 mm on inlet and 0.09 mm on exhaust. By my rough calcultions this is, in imperial terms, 3 thou and 4 thou of an inch respectively. Suggest you double-check my maths, but hope this helps. NB these were road clearances, not for racing.

Alan.

As a follow up to what is said above, I always give the cast iron guides a liberal soak in colloidal graphite oilbefore fitting the valves, to give them a head start in the lubrication side of things!