Pully is stuck

[repsejneslekkim]

Hello.

My first post, hope to get some help sent to Denmark.
My problem is that my pully get`s stuck in engaged position when the motor is warm. My guess is that the inner get`s warm and the bronze bushings get stuck.

Anybody tried this and have a solution ?

Jesper

 

[mckutzy]

Hello and welcome
Can you post pics of your setup, so we can get a better understanding of what were talking about?
Is this a centrifugal belt clutch??
If so sound like the clutch hasnt been oiled.... which should be every 2 hrs of use...

 

[itsid]

Hi,
somehow that sounds to me like you are using a TC and the driven pulley likes to grab on the belt...

I might be wrong, and Mac's actually right assuming you're using a belt clutch
since that'd explain the bronze buishing getting stuck.

So yes, pics please
detailed description on how to post pics just in case you need it

Anyways, to me that sounds like a classic idle speed issue tbh..
when the engine is warm it idles high enough to engage the clutch (no matter if centrifugal clutch or TC)
when cold it drops below engagement speed.

Sooo when the engine is nicely warmed up readjust idle speed and see if that makes a difference.

if you are certain it's a clutch issue

In case of a series30 TC, the problem isn't the bushing at all (it'S there just to raise the belt a bit)
but the cloverhub inside and maybe the weights.. clean and drylube the inside of the bell, and the outside of the clover hub, maybe a tiny bit the sliding rods on the weights.
if you think it's a clutch issue.

and in case it's a centrifugal belt clutch, it's very likely indeed the bushing running dry (as mac said.. needs a few drops of oil every 2hrs of runtime)

'sid

 

[repsejneslekkim]

Hello and welcome
Can you post pics of your setup, so we can get a better understanding of what were talking about?
Is this a centrifugal belt clutch??
If so sound like the clutch hasnt been oiled.... which should be every 2 hrs of use...

Hello.

It is a belt clutch. What can i use to oil it ?
WD 40 ?

Thanks

Jesper

 

[mckutzy]

Regular oil.... just a few drops at the snap ring.. itll seep into the bushing...

 

[itsid]

Hello.

It is a belt clutch. What can i use to oil it ?
WD 40 ?

Thanks

Jesper

a regular centrifugal belt clutch.. odd..
is that a mower we're talking about?
since I haven't seen belt clutches being used on a kart too much
(hence my tc assumption)
with the one exception of cogged (toothed) drive belts on rental and concession karts.
Those on the other hand usually come with a wet clutch, so there's no need for additional lubrication (it's bathed in oil already)

So we talk about this type then:


I like sewing machine oil.. it's nice and clean and thin enough to seep into a bushing quickly..
and it's specifically meant to lubricate rapidly moving parts

Also: it's readily available nearly everywhere (hardware or general stores, pennyshops and supermarkets....and it's cheap )

'sid

ps just to be sure: if your clutch looks closer to any of the two below we would need to adjust the answer

 

[repsejneslekkim]

Hello

It is a 40 series torque converter.

I thourght bronze lubricated itself.


Jesper

 

[Brianator]

In light of this new information, there was a thread recently that touched on this exact subject, turned out the posters hub that the driver clutch slides on was the culprit causing it to stick like yours. The fix was to modify it by "grinding it down" but I think using a file and sandpaper would be a better way and then to dry lube it with dry graphite spray. That bronze bushing is merely a "idler bushing" that prevents creeping forward at idle.

Here's the link to that thread

https://www.diygokarts.com/vb/showthread.php?t=44120

 

[itsid]

Ah so I was right after all.. a TC..
series 40 you sure now or is that again a misnomer?

See.. that'S why we love pictures more than just text..
would've saved us all quite some time

Now,
That bronze bushing MUST NOT get oiled!

chances are it transferes some of the oil to the belt and you loose all transmissive powers.
the belt and sheaves must remain perfectly dry and clean at all times in order to work properly!


Now that bushing is not meant as such,
in a series 30 it's meant to raise the belt slightly in idle.
(while trying to not catch on the TC driver's shaft)
and in a series 40 there are (and must be) two narrower ones..
they act as a guide for the moveable sheave to NOT catch on the spring that sits between them.

while ill dimensioned bushings are not impossible, they're highly unlikely
it's far more likely it just has a burr that's biting.

disassemble the driver pulley,
check the moveable sheave and bushing manually to not catch each other,
find the burr if they do catch and remove only said burr.
test again!

and if you're still having problems and are indeed using a series 40 TC,
then chances are it's not the bushing but the spring instead.

'sid

PS please post pics of your setup

 

[repsejneslekkim]

...
Ps please post pics of your setup

 

[itsid]

Okay,
the good news: it's indeed a series 40..

the bad news: it's the worst imaginable setup of one

Allow me to explain;
the driven of a series 40 is meant to be mounted with it's cam facing inboard
(ie the protruding thingy towards the engine)
That is how it was designed and indented to be used.

Now in rare occasions it is necessary to flip the driven outboard.
(like you have it mounted)
in those occasions the driven MUST BE modified.
namely: it must have a reverse wound spring installed (it's yellow to distinguish the two apart)
and preloaded the other way around (yours is properly preloaded for the red spring.. i.e. INBOARD mount!)
IF the driven is mounted outboard it must be allowed to float 7/8" inwards to prevent belt offset and the accompanied additional unnecessary belt wear (a belt is not cheap.. especially not on our side of the atlantic)
which effectively renders the backplate a terribly useless product!

Sorry, but that TC cannot do it's job at all, and thus is only wasting engine power.
it sticking is more than just likely the offset belt causing the issue,
because of that terrible terrible backplate crap!

three possible solutions..

1) get a longer belt, remove the backplate and install a jackshaft behind the engine to mount the driven inboard as it should be

2) get a yellow spring and install that, preload the driven the other way around (always preload tightening the coil of the spring) and ideally flip the driver inboard do reduce belt offset. you'll need a longer jackshaft to do so (the driven must move a fair bit out)

3) drop the series 40 entirely .. it seems that you got a small enough engine to install a 1" bore series 30 instead. (TAV2 Kit)
it's lighter adds overdrive and handles up to 240cc engines quite nicely (yes also modded ones up to 5500 rpms for sure.. higher rpms and you neeed some tinkering )

Sorry, I know that's not what you wanted to hear,
but that stupid stupid backplate was a massive brainfart
a rather reputable online shop came up with
not thinking it through enough.

And chinese sellers hopped onto that bandwagon without realizing all the drawbacks and worse not even adding the necessary reverse wound spring selling it with the stock setup driven unit.

There is very good reason hoffcocomet never made a series 40 with a backplate themselves.
(and it's not that they didn't like the idea of earning a few bucks more.. it's because it's a bad idea to add such plate int he first place )

'sid

 

[repsejneslekkim]

Hello.

Are you telling me that i either must turn the pully or the driven pully 180 degrees?
Jesper

Okay,
the good news: it's indeed a series 40..

the bad news: it's the worst imaginable setup of one

Allow me to explain;
the driven of a series 40 is meant to be mounted with it's cam facing inboard
(ie the protruding thingy towards the engine)
That is how it was designed and indented to be used.
...

 

[itsid]

Are you telling me that i either must turn the pully or the driven pully 180 degrees?

Not just, no!
you are missing an important point.

again ..
you either remove the stupid backplate and flip the driven (the one with the red spring visible)
180 degrees and be done (as soon as you got the proper belt length to connect the two)

OR you MUST install the yellow spring and reversely preload the driven (swapping the visible red spring against it's yellow counterpart properly installed)
once that is done
you SHOULD still flip the driver (the one on the engine) 180° to have it running inboard,
that requires a longer jacksghaft than you have since the driven must move out a bit.
but that part is basically optional.
If you don't the belt will run crooked, and thus wear down significantly quicker,
and is more likely to get stuck occasionally.

So it's recommended to have the driver facing inboard if the driven is running outboard.

But again.. the ONLY TRUE solution is to get rid of that idiotic backplate!

'sid

ps please keep the quotes brief

 

[repsejneslekkim]

Hello

Thanks a lot for the fine advice.
I will try to find a yellow spring. Are they only found i USA ?

Jesper

Not just, no!
you are missing an important point.

again ..
you either remove the stupid backplate and flip the driven (the one with the red spring visible)
180 degrees and be done (as soon as you got the proper belt length to connect the two)

OR you MUST install the yellow spring and reversely preload the driven (swapping the visible red spring against it's yellow counterpart properly installed)
once that is done
you SHOULD still flip the driver (the one on the engine) 180° to have it running inboard,
that requires a longer jacksghaft than you have since the driven must move out a bit.
but that part is basically optional.
If you don't the belt will run crooked, and thus wear down significantly quicker,
and is more likely to get stuck occasionally.

So it's recommended to have the driver facing inboard if the driven is running outboard.

But again.. the ONLY TRUE solution is to get rid of that idiotic backplate!

'sid

ps please keep the quotes brief

 

[landuse]

Hello

Thanks a lot for the fine advice.
I will try to find a yellow spring. Are they only found i USA ?

Jesper

I am sure you could find them on ebay and amazon