First, thanks to the dozen people who offered their advice
and help. My original concern was that one piston would rise
farther than the other. Well don't know exactly why but I've
fixed that, and another perplexing feature I discovered along
the way; the different level of fuel at the jets.
Most people suspected weak springs, vacuum leak, or binding
piston. After inspection I discovered that the jet was not exactly
centered (a bright spot along the back side of the needle.) As the
needle has no shoulder or gouge worn in it, I'll assume its still OK.
With the pistons out, I observed that I had wet fuel at the top of
the front carb's jet, but that the fuel level was way down the
back jet. Checked the floats, both set at 1/8" per the book.
Head scratching followed, then dinner, then more scratching.
Sticking my fingers in the bowls verified Archimedes principle;
the fuel level in the bowl determined the level at the jet.
I recall someone's observation that the engine is tilted. So it
is, and enough that the front float is roughly 1/8" higher than
the jet. Then I observed that the front float was the one-piece plastic
type (the only type you can now get), while the back float had
the metal tab connecting to the hinge pin. So I switched floats,
set the front one low, and now have fuel just below the surface of
the jet, fore and aft.
Reassembling all, I tuned the carburettors, the observed the pistons
moving in synch, same distance.
So I don't know what was wrong, but its right now! Hansen Colortune
in progress (drive to and from work tomorrow, pull #1 and #4 plugs,
adjust mixture.) Hope to see some of you at Berkeley VA this Sunday.
Cliff Hansen
chansen@exis.net
1966 TR-4A CTC 64615L
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