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TR6 Hesitation, while turning, I'm stumped.

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PDIGIO_6x3 said:
Late to the discussion, but you can also do a test by pulling the choke cable slightly, enough for the first inlet on the starter box to bleed in fuel. If the problem stops, you are starving for fuel. I am experiencing a fuel starving problem right now, however I have three ZS carbs and I think the mechanical fuel pump, (original type) is not keeping up with the amount needed. I get stuttering through all gears and looking at the plugs, they're looking very lean burn. I also installed a glass fuel filter inline just in front of the carbs, and it always looks empty, or very little fuel in it. So, I'm looking for advice on a better fuel pump.
Click to expand...
I'll give that a try. As for the filter, I didn't they they were ever full of fuel.
 
Well, the whole problem was only partially fixed. So to sum up:

Turns out, when testing, we noticed a hestiation/light surging in 2nd and 3rd gear between 2500 and 3000 RPM when holding steady throttle as well as the original problem. Also, it had an occasional hesitation starting out very slowly from a dead stop. The left turn sweeper hestitation was only rearing its ugly head when moving (not from a dead stop) and in 2nd gear trying to accerlerate using around 2200-2500 RPM. New cap, new rotor, new Petronix coil (an old under the cap ignitor), no issues with any of the leads could be found. No crimped fuel lines (most are new), new tank, new vent lines, new fuel pump, new filter.

The hesitation problem was cured by raising the needles to ensure better fuel delivery and going to 10W40 in the dash pots. The turn issue is still there. The garage thinks its the Crane cam the previous owner put in coupled with the original ZS carbs. I'm dubious.
 
Back to basics ... In your first post, I see:

BwanaJoe said:
I have a 72 TR6 that I've recently had the carburetors rebuilt, fuel pump replaced, the gas tank replaced, and the metal fuel lines all replaced.
Click to expand...

Did the problems exist *before* you had all the work done?

Tom M.
 
PDIGIO_6x3 said:
Late to the discussion, but you can also do a test by pulling the choke cable slightly, enough for the first inlet on the starter box to bleed in fuel. If the problem stops, you are starving for fuel. I am experiencing a fuel starving problem right now, however I have three ZS carbs and I think the mechanical fuel pump, (original type) is not keeping up with the amount needed. I get stuttering through all gears and looking at the plugs, they're looking very lean burn. I also installed a glass fuel filter inline just in front of the carbs, and it always looks empty, or very little fuel in it. So, I'm looking for advice on a better fuel pump.
Click to expand...
The original mechanical pump shouldn't have any trouble keeping up enough flow to three carbs unless it's failling and needs to be rebuilt or replaced. If carbs were outpacing fuel supply from a pump in good working order, you'd be measuring gallons per mile instead of miles per gallon.
I do think going to an electric is a good idea if originality isn't a issue. No risk of a diaphragm splitting and dumping fuel into your sump if there nothing there but a blanking plate.
 
I had this once many yeas ago when i worked in a garage, tried everything, then a lucas engineer told me to change the coil,
if the oil in the coil gets low, pulling sharp turns, what is left of the oil goes up the one side of the coil and causes a missfire
 
BwanaJoe said:
Oil?
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Old style ignition coils are filled with oil, just like the transformers on the powerlines to your house. They basically work the same way as well, with one just using higher input voltage to induce a lower output voltage, and one using a lower input voltage to induce a higher output voltage.
 
And if a coil is installed horizontally ... the oil pools on one side, causing the wires to overheat in the area where the oil isn't!

Result: slow coil failure, and poor sparks cause ignition problems!

Ask me how I know ...
 
BwanaJoe said:
Ok, new one on me. But, Pertronix Flame Thrower coil installed.
Click to expand...
Those are known to leak. Happened to 2 of mine and to a Forum friend as well.
Feel around the bottom of the coil for oil...There are epoxy filled coils...the Bosch Blue for instance.
Green Wires TRF 001_zpsq4w08aes.jpg
 
You stated you installed a, "New cap, new rotor, new Petronix coil". I do not know if the iner modual could cause your problem, but I would still replace the new electronic stuff and go back to original until I figured it out.

Steve
 
But if the problem existed before he did all the updates, wouldn't that exclude the updates from being related to the problem?
 
This was a problem that GM dealt with in the mid 00’s with their Cobalt model if I remember correctly; do you have any weight on your key ring that pull on the key causing poor electrical contacts while in a turn?
 
charlie74 said:
This was a problem that GM dealt with in the mid 00’s with their Cobalt model if I remember correctly; do you have any weight on your key ring that pull on the key causing poor electrical contacts while in a turn?
Click to expand...

Nope. Just an old leather key fob.
 
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