hardened valve seats

[Michael D. Porter]

Hans Hintermaier wrote:
> 
> Hi there, metallurgists and engine-recyclers.
> Does anybody of you know what (generally available) material
> I can use for unleaded-fuel-valve-seats? I am just working on an old
> motorcycle with aluminium head, which needs the valve seats to be
> replaced. Could be X210 Cr Wo 12 the right thing?

Wie gehts, Hans--
Unless you've have a milling machine or the right set of piloted cutters, 
it's doubtful you're going to be able to install the seat inserts 
yourself.  Visit your local automotive machine shop and tell them what 
you'd like to have installed.  Most auto machine shops can get inserts 
from their suppliers in almost any size.  As for the composition of an 
insert for unleaded use, I'm doubtful the above would be suitable--if the 
Wo is meant to be wolfram (tungsten), 12% would make the material far too 
brittle, I think.  I would guess that the material is extremely low 
sulfur, high chromium, some molybdenum, with a small amount of nickel and 
an even smaller amount (0.2-3%) tungsten.  We may have it in what SAE 
papers we have at work--given a bit of time, I'll check.
Cheers. 

-- 
My other Triumph doesn't run, either....