Metric Mechanic Roadtrip

#41

Scott and Rich,
Thanks much for detailing the building experience and lessons. Great! We all appreciate this info. I think there may be a biz here for MM - Mechano Tourism; take a few days at the super machine shop and build a new engine. Kinda like a Dude Ranch:laugh:

I cant wait to hear and ‘feel’ these well balanced engines and compare to our typical units. At future race weekends, we may want to convene on Sunday morning and worship these beauties, listen the the perfect balance and tolerances, and strive to channel some of that balance into our own lives.:wink:

One question, the dropped or broken valve has ruined two bottom ends for me. Did you learn any extra protection techniques to prevent this failure? It would be a shame for a little issue to ruin a lot of good work.

Thanks again for sharing!

#42

I had cause to come back to this old thread and I found that this question never got answered. I don’t know much about top ends. What would over-stress a valve? I dunno. I don’t see how an improper rocker adjustment would do it, nor a sticky valve seal. Maybe Rich or ChuckB will chime in with an idea.

#43

A dropped valve is usually the result of an over rev. The valve hits the piston and gets bent and the repetitive bending forces cause the valve head to separate from the stem. A bad enough over rev can just bust the head right off the stem. A broken valve spring or keeper can also cause a dropped valve.

#44

What Jim said+++ chuck