> So, here's my question. What could cause the car to require the choke
> to run?
I agree with Jim, for $900 your mechanic should at least be able to tell you
why it doesn't run right ! Legal action may be required here. If they
didn't fix the problem, you should get your money back. Did the engine run
OK when you picked up the car ?
By 73 the US-spec engines were tuned pretty lean, so weak ignition is a
definite suspect, IMO. Your PO didn't by any chance change the coil ?
73-on TR6 take a different coil than all earlier Triumphs, since they have a
ballast resistance built into the wiring harness. The wrong coil could be
the problem. And while I don't think it's the problem, it couldn't hurt to
invest $10 in a set of new spark plugs, JIC. It's sometimes possible for
spark plugs to glaze even when they're almost new, causing all sorts of
strange symptoms.
> I haven't been able to locate any leaks... but it was windy
> when I tried the propane test.
Try disconnecting and capping the line to the brake booster. A failed
booster can be a hidden intake leak. WD-40 is more controllable when
checking for leaks by spraying at the suspected leak point (although granted
it's also messier). I don't recall offhand what the PCV system looks like
on a 73, but it might also be worth disconnecting and capping it's vacuum
line(s) as a test.
> Could the carbs be jetted wrong?
It's possible, but unlikely, IMO.
> Any suggestions would be greatly appreciated.
Have you checked the fuel pressure ? (Temporarily tee a vacuum test gauge
into the fuel line)
Is the engine warming up properly ? (cold engines require choke)
Do the carb pistons rise (and more importantly fall) smoothly when lifted by
hand ? Do the dampers have fluif ?
Is the timing set to about 10 degrees BTDC with the vacuum retard
disconnected ? (Yes, I know that's not what the book says, but it's the way
to get the engine to run right.)
Most of the time, problems like this are something relatively simple, it
just takes a mechanic that both has some clue about how a British engine
runs, and is willing to take the time to check the simple things first.
I've seen way too many professional mechanics that think they can diagnose
the problem without even seeing the car. And needing choke to run does NOT
necessarily mean it's a carburetion problem.
Randall
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