Torque converter belt slipping

[bnt5]

I have a comet 40 torque converter on my buggy go kart and whenever the kart is under a load the belt on the TC slips badly and smells like burning rubber, this makes climbing any sort of incline a non-existent. I have cleaned and lubed the driver and driven according to specs, not sure why this is still happening? Any tips would be helpful thanks, Bill

[speedshopmike]

remove and clean the belt with (i use brakekleen) something that won't hurt rubber, clean the drive surfaces of both pulleys with like chemical also.
naybe your belt has stretched; add tension in 1/8" or so increments if possible on your cart.
is your driver fully expanding when revved?
is your driven staying closed (large) when power is applied?

[bnt5]

Driven opens up when power is supplied. I purchased a new belt thinking that the old belt was worn, well upon measuring the new belt it seems to be the same measurement as the old one...they are both under 7/8" wide at the top and I thought that comet 40 belts needed to be 7/8, go figure. I think there might be too much of a gap around the driver pulley when I pinch the belt, not sure what the tolerances should be.

[speedshopmike]

the driven should stay closed (large) until you're moving well along in "low" gear.
sounds like the driven spring is spent.
my comet 30 had the same problem.
unsure if what i did to test my 30 will work on a 40 but i think it would:
find some sockets or similar objects and ziptie them into the driven pulley under the cams so it's unable to open/shrink it's effective OD.
test drive.
if it now accelerates and climbs hills w/o belt smoke replace the driven spring.

[bnt5]

should I look at different spring than stock? The one I have is yellow for the 40 series

[speedshopmike]

someone who knows more than me (which won't be tough at all) will have to answer that; the only experience i have w/ a 40 is my neighbor's buggy when i help him out.
stiffer spring will delay the "upshifting".
a 30 series has 3 holes to select from to fine tune tension; maybe a 40 does too.
i'd delete this whole thread and repost in the torque converter section of this forum, instead of here; you'll likely get lots more useful replies

[bnt5]

thanks, got everything back together and it ran better than ever...which for a 9hp engine is kinda ok . Appreciate the tips!

[speedshopmike]

great, what turned out to be the problem?

[bnt5]

The only thing I replaced drive related was the belt, however I did disconnect the governor, weld up a new pipe and muffler and installed a hi-flo intake. I am pretty sure that it was the belt that was worn, but it was soooo close to the new one measurement wise that it would be very difficult to diagnose.