TR6 Hesitation, while turning, I'm stumped.

[BwanaJoe]

Well, after cleaning up the carbs I had the bottom end of the carbs checked out by my mechanic. So, the floats were adjusted and the needle slightly raised. Nope, still does it. I am getting to the point where I am going to blow cash on Webers...

 

[PDIGIO_6x3]

I can't see why turning a corner would have an effect on fuel flow. Does it happen turning right and left, or just in one direction? Refresh my mind, are these ZS carbs?

 

[auprichard]

Many years ago Ken Gillanders from British Frame and Engine wrote about a TR3 which kept hesitating and missing on turning corners. He went through the car and couldn't find anything wrong until he noticed one of the engine mounts had rotted out. The engine was moving / rotating on corners and interrupting fuel flow.

I realize it is a long shot, but I thought I'd at least throw it into the mix.

 

[PDIGIO_6x3]

To me, this sounds more relatable to ignition. Maybe a loose wire, bad coil, cap, or rotor. I had a lot of minor, unexplainable performance issues when I had the original points setup. I changed to the Pertronix ignition, very reasonably priced, and all the sputtering, missing, and momentary loss of power is gone. I have three ZS, and that’s an even greater invitation to problems. Has there been any change to the ignition system yet?

 

[BwanaJoe]

To me, this sounds more relatable to ignition. Maybe a loose wire, bad coil, cap, or rotor. I had a lot of minor, unexplainable performance issues when I had the original points setup. I changed to the Pertronix ignition, very reasonably priced, and all the sputtering, missing, and momentary loss of power is gone. I have three ZS, and that’s an even greater invitation to problems. Has there been any change to the ignition system yet?

Pertronix Ignitor, Pertronix coil. The ignitor is decades old. I may, at this point, change it out just to see. The coil is new.

 

[BwanaJoe]

Many years ago Ken Gillanders from British Frame and Engine wrote about a TR3 which kept hesitating and missing on turning corners. He went through the car and couldn't find anything wrong until he noticed one of the engine mounts had rotted out. The engine was moving / rotating on corners and interrupting fuel flow.

I realize it is a long shot, but I thought I'd at least throw it into the mix.

I replaced the engine mounts about 10 years ago. Doesn't hurt to check again...

 

[BwanaJoe]

I can't see why turning a corner would have an effect on fuel flow. Does it happen turning right and left, or just in one direction? Refresh my mind, are these ZS carbs?

Left, ZS dual carbs. Rebuilt and cleaned last year and again this year.

 

[PDIGIO_6x3]

I apologize, just saw this reply. We're on two different posts. Let me ask you, did you notice how high up your rotor is sitting after you installed the Pertronix? Did you replace the original rotor? I know that there can be a condition where the center contact for the cap is compressed into the cap excessively because the rotor is sitting up higher than it should.

 

[BwanaJoe]

I apologize, just saw this reply. We're on two different posts. Let me ask you, did you notice how high up your rotor is sitting after you installed the Pertronix? Did you replace the original rotor? I know that there can be a condition where the center contact for the cap is compressed into the cap excessively because the rotor is sitting up higher than it should.

Rotor and cap have been replaced. The rotor is pushed all the way down on the post. The rotor arm is not loose.

 

[charleyf]

Rotor and cap have been replaced. The rotor is pushed all the way down on the post. The rotor arm is not loose.

Have you tried turning a full circle and see what happens?
Does the car die and stay that way or pick back up?
You may need to make this a big circle to get the RPM you need. Also try letting off the gas momentarily and then hit the gas.
If you think about the mechanics of this operation. You normally approach the corner and let off the gas. Then hit the gas midway in the corner.
That is why the full circle test might tell you something.
Charley

 

[Brian_Jones]

Here is a long shot, after all the sensible suggestions above: Bad ground strap to the engine block. Easy way to check: add a second ground connection to the block and see if anything changes.

It could be that the frame flex of turning interferes with a poor ground connection.

 

[Hamish Racing]

Hope you find the issue and let us know. Always good to find out the result and cure.

 

[Gerald_Gordon]

For some reason that I do not understand, the glass filter in my TR4 always looks nearly empty, too, yet the car runs well under all conditions. (If Randall Young, "TR3driver," were still here, he could probably explain that. Perhaps he has already done so.)

 

[charleyf]

For some reason that I do not understand, the glass filter in my TR4 always looks nearly empty, too, yet the car runs well under all conditions. (If Randall Young, "TR3driver," were still here, he could probably explain that. Perhaps he has already done so.)

I can not replace Randall, but I assume you are referring to an extra filter on the fuel line between the pump and carbs. Mine does the same thing.
I have tried all sorts of ways to try to fill it but it always reverts to that nearly empty look.
It would be interesting to see what the filter looks like while the engine is at 3000+ RPM.
Because only the bottom part of that filter is getting used. I have learned to rotate the filter after several thousand miles.
Charley

 

[PDIGIO_6x3]

I can not replace Randall, but I assume you are referring to an extra filter on the fuel line between the pump and carbs. Mine does the same thing.
I have tried all sorts of ways to try to fill it but it always reverts to that nearly empty look.
It would be interesting to see what the filter looks like while the engine is at 3000+ RPM.
Because only the bottom part of that filter is getting used. I have learned to rotate the filter after several thousand miles.
Charley

If we look at this logically, the fuel circuit is vented in the carburetors. the air in the bowl will remain as long as the pressure needed to pass the fuel down the line doesn't exceed the pressure the air exerts on the fuel downstream. There's no airtight point on the fuel circuit. Even if you manually fill the glass bulb, the fuel will level out and the air will remain. There has to be venting, otherwise fuel wouldn't flow.