Valve seals

[73ironhead]

Hya people, just re-did the top and a valve seized after only 55miles; took it to the machine shop and discovered they had put a seal on the stem that I did not see on the book. Seal or no seal?

cheers, Lazio


-patience is passion tamed

[jmanjeff]

stock did not have a seal 
Vave guide oil seals will require machining of valve guide and / or collar to get the correct overall guide height

[help-u2]

jman correct.. no seal stock.  and not really needed.  let some oil get to guides/valve.
that and/or clearances is why it seized.   i dont know what combo you using...
i use a bronze guide with stainless valve on my hot rod.  yepper it puffs a bit.  just like my XR racer did/sposta.  one quart every 1000 miles is normal...
too bad the machine shop took it on themselves to change it for you.  they should change it back for free...

[73ironhead]

thanks...machine shop will change for free and..I never minded peeling the engine one extra time...L.

[saltcaveminer]

yes valve seals were not stock but i would like to know more about what combination was installed.valve seals did not cause the seized valveSalty

[fulldress79]

Make sure there is enough valve stem to guide clearance.Air cooled motors of course need more than water cooled. bring them the factory clearance specs to be sure

[73ironhead]

there is no escaping Salty..good on'ya mate, you're right it wasn't the seal that seized the valve but a combination of ; 1. overheated engine during break-in...2.bronze guide instead of iron; the R. EX. bronze guide actually came loose ...I think the machine shop was training a new mechanic on me...whatever...did not charge the second time but had to paint the whole thing again.....L.

[saltcaveminer]

I'm glad the valve issue is resolved.now on the break in try to follow the S&S break in procedure.(short run times at first 30 sec,60sec,90sec,etc.with full comedowns in between.no hot rodding for at least 1200mi.Salty

[73ironhead]

yea, I read about the heat cycle and I may change to a bigger jet for the break-in phase 'cause she's running real thin...L.