[TR] TR3A Choke Question

[Randall]

> What kind of oil are you using in the dash pots?  If the oil 
> is too heavy, it may overdamp the pistons, causing them to 
> rise too slowly and momentarily weaken the mixture, causing 
> the hesitation. I find 3 in 1 is about the right weight. 

Actually, it's just the opposite.  Heavier oil makes the mixture go richer
right after you open the throttle.  Using oil that is too light can cause a
"lean bog" (like Jim described).

The book actually recommends 30 weight for temps between 40F and 70F; 40
weight above that.  Optimum for you may vary somewhat, depending on engine
condition and so forth; but I have always found that performance suffers
with less then 20 weight

>   The choke cable is hard to pull 
> out.  Takes two ands
> > to pull out and then twist to lock.  That's to really get the choke 
> > levers to move both jets down.  Is this normal or maybe I 
> need a new choke cable.

Not normal, but unfortunately rather common.  Did you polish the jets when
you had the carbs apart?  Originals were supplied polished, but the
replacements I've seen have been dull.  Dull means a rough finish, which
greatly increases the friction against the glands.

The linkage also goes together in an odd way.  If you put it together the
way it seems it should go, it's harder to operate the choke.  The two
clevises hang out behind the levers, rather than straddlings them.

I like to replace the gland sping (inside the jet housing) and the return
springs during a rebuild, especially if you don't know the full history of
them.  It's not uncommon for people to stretch the gland spring out a bit,
in an attempt to get the glands to quit leaking.  The extra pressure
increases friction, to the extent that often the jets won't return after
using the choke.  So then they shorten the return spring.  Both actions make
the choke more difficult to operate!

-- Randall
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