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I have this tool but have never used it. When the metal ball is screwed in position it does not appear to seal all the way around the edge of the ball? Does this matter for getting an accurate reading or is this part of the design? I thought that maybe the screw shaft was slightly bent? Also what is the smaller screw for?
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TR2/3/3A SU balance tool
- Thread starter karls59tr
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That small screw should be the pivot for the glass tube. The spring is there to hold it tight to the body for a decent seal.
The part that you were adjusting, as you probably saw in the instructions, is the flow control -- and yes, even "fully closed" there should be a gap there for air to come through.
Some carbs / engines draw relatively little vacuum and need that flow control almost closed. I used this tool on a 600cc motorcycle with one carb per cylinder, and even "fully closed" wasn't closed enough to lift the ball. I had to tape over the opening! I think a dual-carb TR should have a much stronger vacuum than that.
The part that you were adjusting, as you probably saw in the instructions, is the flow control -- and yes, even "fully closed" there should be a gap there for air to come through.
Some carbs / engines draw relatively little vacuum and need that flow control almost closed. I used this tool on a 600cc motorcycle with one carb per cylinder, and even "fully closed" wasn't closed enough to lift the ball. I had to tape over the opening! I think a dual-carb TR should have a much stronger vacuum than that.
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Listening through a piece of fuel hose to the sound of the air at the carb opening is the best way to balance carbs.
Bob
Bob
I took a hot wire anemometer ,a 1 1/2 pvc pipe with a 1/4" hole in the middle for the probe to get the recommended 4x diameter for laminar flow and best accuracy, with a foam collar to seal around carb face.
THis most accurate method I could think of was no more accurate than listening,as mentioned by bob,with a small hose or watching the pistons go up and down with the air cleaners off.
THe problem with the op's gauge is that as soon as you place it on the carb the rpm changes and engine starts to run rough,
Tom
THis most accurate method I could think of was no more accurate than listening,as mentioned by bob,with a small hose or watching the pistons go up and down with the air cleaners off.
THe problem with the op's gauge is that as soon as you place it on the carb the rpm changes and engine starts to run rough,
Tom
I took a hot wire anemometer ,a 1 1/2 pvc pipe with a 1/4" hole in the middle for the probe to get the recommended 4x diameter for laminar flow and best accuracy, with a foam collar to seal around carb face.
THis most accurate method I could think of was no more accurate than listening,as mentioned by bob,with a small hose or watching the pistons go up and down with the air cleaners off.
THe problem with the op's gauge is that as soon as you place it on the carb the rpm changes and engine starts to run rough.
BTW my Visala Veloci-calc temp,humitidy and airflow meter was I think about $2500 so not an option for most.
Tom
THis most accurate method I could think of was no more accurate than listening,as mentioned by bob,with a small hose or watching the pistons go up and down with the air cleaners off.
THe problem with the op's gauge is that as soon as you place it on the carb the rpm changes and engine starts to run rough.
BTW my Visala Veloci-calc temp,humitidy and airflow meter was I think about $2500 so not an option for most.
Tom
CJD
Yoda
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Karl, the gage you have is a good gage. Use the brass knob to control the opening to bring the ball in the tube to mid-range. Then move to the second carb and compare. It works as good, or better, than anything else you can use. If it affects the running of the engine, then it is closed off too far. Once you set the ball mid range, it has a negligible affect on mixture or airflow.