Weibang WB486SKV-R(48 Pro BBC)

[Kevin]

Hi everyone,

I have in my workshop a Weibang Pro 48 BBc and the owner is complaining about the lack of power from the drive. Would this be the same issue that affected the bigger Pro 56 where the drive belt tensioner/speed control unit had been subject to a subsequent modification?

Regards

Kevin

[Mick]

Hi Kevin.  Yes If it's just lacking power then it does sound like a belt issue.  Possible the intermediate pully has lost it's spring tension, the springs were pretty soft. Check the belts haven't gone thin due to wear.

Also something to look for is make sure both rollers are driving, if only one roller is driving that can give you a similar lack of power feeling. 

[Kevin]

Hi Mick,

Thanks for your reply, always appreciated.

Both the rollers drive but I have yet to look at the belts.

Do you know if the intermediate pulley was modified on this model the same as the 56 pro?

Cheers

Kevin

[Mick]

Kevin, as far as I'm aware if it's a Weibang Legacy it can have the modified tensioner pulley if not already fitted.

[Kevin]

Hello again Mick,

The belts are pretty worn but I have also noticed that there is a large gap between the top and bottom of the upper pulley (nearest the securing nut and circlip).And the top half of the upper pulley does not move on the splines, I am assuming it is fixed and that only the bottom half should move?



I don't see enough of these to know what is standard.

Looking back I did fit a new tensioner to this machine about eighteen months ago.

Do you have any thoughts?

Thanks

Kevin

[Mick]

.And the top half of the upper pulley does not move on the splines, I am assuming it is fixed and that only the bottom half should move?

Correct, just the lower half of the top pulley moves.  If you look between them you can see the ramps which the top half rides up on, hence why it has to be fitted the right way up so the rotation is in the right direction.

If the belts are worn I would change them for sure, it's surprising how worn and thin they can get, normally quite noticeable when you compare old and new. 
 

[Kevin]

Hi Mick,

The pulley was a bit sticky on the ramps. I think water must have got in some how. I gave it all a good wire brush and then checked the pulley half climbed the ramps.

I have fitted new belts and it works as it should do.

Thanks for all your advice.

Kevin

[Mick]

Good job, glad it worked out.  These machines are so reliant on belt size to keep them tight, so the slightest wear on the sides of the belts results in them going loose.  A bit like the older Hayter system with the variable speed, they are terrible.