frankh
Well Known Member
I agree
there are so many old wives tales in aviation...Is there one shred of evidence anywhere that lead really does lubrictae valve seats...and even if it does, does it really make any difference to the longevity of the top end of the motor?
Assuming the answer is "NO" I'll continue to use unleaded Mogas for as long as I can find it.
Lets hope we can prove the ETOH will also work as well as 92 Octane mogas...Even if we are getting ripped off.
Frank
I recently completed what was probably the fourth top-end overhaul on a 1974 Harley Sportster that I bought last year. With 9.5:1 compression and hemi heads, it was designed to run on 97 Octane leaded premium, but it's obviously been run on unlead for at least 30 years. The stock valve seats on this engine are merely ground out of the raw cast-iron heads -- they aren't even steel inserts. Although you can buy "no-lead" hardened valves and seat inserts for it, most people don't bother.
So what did I find when I pulled the heads? The factory original valve seats were still perfectly servicable after normal grinding for a new set of valves. The valves I replaced were NOT hardened "no-lead" valves, and I didn't waste my money on hardened replacements.
So much for "Valve Recession" theory.
there are so many old wives tales in aviation...Is there one shred of evidence anywhere that lead really does lubrictae valve seats...and even if it does, does it really make any difference to the longevity of the top end of the motor?
Assuming the answer is "NO" I'll continue to use unleaded Mogas for as long as I can find it.
Lets hope we can prove the ETOH will also work as well as 92 Octane mogas...Even if we are getting ripped off.
Frank