> I just read your question about the mixture control. I have a 415-C >with a C-75 Engine. My mixture control is also safety wired. I've asked >other coupers about this and there are a lot of them that are the same.
I'll chime in as the resident devourer of literature about all
vintage GA craft.
I've seen a lot of palaver as regards this very question on the
Cessna 120/140. Many of the 120's came with no mixture control,
and it is a popular retrofit.
It is unclear whether its original omission was an engineering,
simplicity, or ecomic decision.
Some say the mixture control on the carbs that most of these engines
use is not real effective, but makes up for it by being terribly
touchy :-) In other words, it doesn't lean the engine very well,
but kills it pretty reliably.
Others say 'rubbish, if the mixture control kills the motor, it's
because the carb needs a rebuild. Mine works fine. So there!'
The truth is probably somewhere in between.
Some folks seem to have an STC'd alternate carb, which they swear
by.
>I don't know of any C-75's that are not safety wired but I've seen some
>C-85's that have a control inside. I've had my coupe since 1986 and
>have seen no negative results.
The picture may change significantly for those who, for whatever
reason, run their coupes on 100LL. Mixture *is* documented to be
a critical element in lead-fouling for the little Continentals.
> If I were you I'd leave it alone. For
>one thing, if it runs a little on the rich side it will also run cooler
>and probably give you longer engine life than if it were running leaner
>and hotter. Reckon???????
Lead fouling aside, probably. Excessive rich can wash the oil off
the cylinder walls, which leads to premature wear. But who really
flys an Ercoupe so high with any regularity that the mixture goes
ruinously rich?
Greg
--
Greg Bullough | AFM Local 1000 AFL/CIO
[EMAIL PROTECTED] | K2GWB
| PP-ASEL
www.eclipse.net/~gwb for Compass Rogues & NY Chantey Sings
<<attachment: winmail.dat>>
