68 shovelhead valve key
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From: la la land jerzey
Looking at the head from the right side of the engine it is thought a hemi design with the valve Keys opening at 3 o’clock as well as the rocker arm pad center
the load is spread across the valve - if its at 12 o’clock looking at it from the right side the load can rock the keys as spring pressures are not hi - on the seat pressures - now i never seen one come out but i have seen wear on the retainer taper - does it matter - who knows - as i said never seen one come out and never really spent the time to investigate this long term — but someone did and thats y
the load is spread across the valve - if its at 12 o’clock looking at it from the right side the load can rock the keys as spring pressures are not hi - on the seat pressures - now i never seen one come out but i have seen wear on the retainer taper - does it matter - who knows - as i said never seen one come out and never really spent the time to investigate this long term — but someone did and thats y
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From: Cental, MI
I guess I was taught that the "split" should be perpendicular to the front rear axis... ie front to rear... not side to side...Are they like that after ya run yer Engine???? Not exactly... No... Exactly like the Very Best truing job on the flywheels.... Wanna pull yer hair out????
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From: la la land jerzey
a rotating exhaust valve at 1600 degrees will bring the heads valve seat into a puddle - and it did just that
still valves at the time some one in the know if you asked him would have told you all the reasons it was Going to work - but it was 100 years of still valves that did work and still do today
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Cruiser
Joined: Oct 2009
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From: Edgewater, FL.
I am more recently familiar with Lycoming engines. Lycoming and Continental use a rotater cap to rotate the exhaust valves.
When I google it
Most valves in an operating small engine rotate about the valve stem axis at varying rates. Valve rotation has an overall positive effect on valve life. Rotation provides improved temperature distribution in the valve head and a mild scraping action that cleans the valve interface of any crushed combustion deposits.
I assumed Harley did as well.
When I google it
Most valves in an operating small engine rotate about the valve stem axis at varying rates. Valve rotation has an overall positive effect on valve life. Rotation provides improved temperature distribution in the valve head and a mild scraping action that cleans the valve interface of any crushed combustion deposits.
I assumed Harley did as well.
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From: la la land jerzey
Not that i have ever seen 20 different motorcycle manufacturers do a rotating valve - small engines are throw away for the most part its cheaper to get another new one then to fix an old one - plus a small engine usually is at a 1/2 engine speed
i have seen the damage that was done on chevy engines from turning the valve - unlike small engines its not a big deal very light valve spring and super mild cam shaft and almost no compression
i have seen the damage that was done on chevy engines from turning the valve - unlike small engines its not a big deal very light valve spring and super mild cam shaft and almost no compression
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From: Cental, MI
In my minimal experience, I see valves rotate some bit, even if it is Not a Design Feature... good??? Bad??? I consider it a Simple Fact...and deal with it... or Not
Edit; If the Remac says my springs are in (my) spec.. I'm Good!!!!
Edit; If the Remac says my springs are in (my) spec.. I'm Good!!!!
Last edited by Racepres; Jun 5, 2023 at 10:03 PM.
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