Notoriously malfunctioning torque converter

[BMPoland1993]

Welcome all,

I am writing to you with dire need of help concerning my 40-series torque converter.

Let me picture the problem: When depressing the gas pedal, the gokart starts moving slowly, as usual.. crawling in fact. As soon as I add more gas the driven unit starts to malfunction in a worrying way. Firstly, it sounds and looks like it's not supposed to. The whole unit starts shaking and screeching violently, the spring part jumps the buttons and when adding more gas suddenly bang! And the driven sucks in the whole belt.

The entire spectacle is a nightmare. Looks like something is incredibly wrong with the converter.

Now, I have tried to amend the problem by taking the driven apart and winding it a little more tightly by drilling another hole for the spring to sit in to. Didn't help. I have tried various combinations, for example all three holes and even winding the spring clockwise direction as well as counter clockwise.

New belt, drive unit new and graphite greased, works perfectly smoothly.

The gokart is particularly heavy and the rear tires are 20". 420cc engine with 54 tooth sprocket.

So far I have been unable to fix the problem with the converter myself, hopefully this community will know more on how to help.

Thank you,

B.

 

[Millwright]

Any pics of your set up?
How heavy is "particularly heavy"
Size of drive sprocket?

I'm new to using a 40 series and trying to gather as much info as possible. I probably can't offer you any words of wisdom, but hope to learn from your experience here.

 

[madprofessor]

Unsure about your terminology, "whole unit", "drive unit new", "driven unit", "spring part', "jumps the buttons", "winding spring clockwise and counterclockwise". Lets talk in terms I know................
The "whole unit" would be everything about the torque converter, including the driver, the driven, the belt, and the backplate if provided. Need to know if you did get the backplate or not.
The "driver" pulley is the variable centrifugal clutch that mounts directly onto the motor shaft.
The "driven" pulley is the larger variable pulley that's mounted on a jackshaft that's either built into the backplate or, in the absence of a backplate, is mounted on a separate shaft that's part of the gokart.
Can you explain in this way what the "whole unit" (torque converter) is doing, if it has a backplate, what you mean by "jumps the buttons", what the "spring part" is, what parts are new, what "sounds and looks like it's not supposed to", what's "shaking and screeching violently"................
One at a time please.

 

[bob58o]

You driven unit is probably flipped the wrong way. Flip the driven around or buy a reverse wound spring for it. Show us a picture if possible. The driven unit on a 40 series should NOT be installed with the spring outboard as is seen on these 30 series kits unless you have the reverse wound spring. The standard 40 series driven unit with standard spring needs to be installed with the spring on the inboard side.
Peace

 

[madprofessor]

Comet Drive Belts | Comet Torque Converter Belts | Go Kart Belts (gokartsupply.com)
Go to the attached website, scroll down past the diagrams for 30 series, CAT 99 Series, 20 series, TC88 Series, to the 40 and 44 Series. Look just below those belts at the diagram just above "500 Series Belts", that's the diagram for your 40 series as they are from the factory. (The page layout for the diagrams is a little confusing.)
Read all the troubleshooting info that fills the rest of the page, you should find it helpful.