56 pro quickly got slow after new drive belt

[Lmcc22]

Hi all,

I've an old 2006 56 Pro.
The drive was terrible so I left it to get serviced, believe it got a new belt as well as engine service.
On return it drove real well, like a fast paced walk and as fast as it ever was, brilliant mower for near 20 year old.
I've a large garden and after an hour of cutting it has slowed to a half paced walk.
Is this normal?
And if not how would I go about quickening it up again?

Thanks in advance

[Mick]

Hi Lmcc22, and welcome to TGMF.

I'm assuming the engine is still running at the same speed as it was when it was driving normally?

What's the exact model number of your machine on the silver sticker o the top of the deck.  Should be three number and a letter (Example 566G). Or if that's missing just attach a photo of the machine to a reply here.  Just so we know what we're looking at. 

[Lmcc22]

Hi Mick, apologies for the delay I missed your reply and thanks in advance.

It looks to be a 2008 model, 561F, attached a photo of the sticker on the deck.

Since first posting the drive has got slower again. So when the belt was first changed it was a fast paced walk, 2 cuts later (about 5 hours cutting) it's a slow pace walk, about half the original speed.

Engine is running at the same speed, it has a manual throttle, so that's full throttle to avoid confusion.

I'm wondering has the new belt just stretched a little and should it need it adjusted under the deck, is this a thing?

Can't find any maintenance manuals online for this model, given its age more than likely. The mower cuts like new and drives brilliant straight after that new belt.

Any help much appreciated.
With thanks

[Lmcc22]

Attached

[Mick]

Thanks for the info.  Did you change both belts, or just  one of them?  Also I would suspect that the Variator pulley between the two belts is not doing it's job properly which is quite common on these machines.

Inside the Variator pulley there is a couple of tin rings which have little tabs on them to cover the plastic ramps which push the pulley halves together and keep the belts tight.  These little tabs tend to break off. Quite often when the spinning the Variator by hand with the belts removed these broken tabs fall out.

Variator pulley Part number 411001 (I will warn you though, they are not cheap).

All this is assuming you've changed both belts, and that the gearbox is good and clutch inside it isn't slipping.

[Lmcc22]

Both belts I believe Mick.

Would a faulty variator account for the drive being good when the belts were first changed?

The variable speed drive adjustment on the left handlebar doesn't work by the way, never has in the time I've gotten it, but again when it come back with the fresh belts it was moving fast.

Also how would I know the drive clutch/gearbox you mention was the cause of it moving fast with new belts but then slowed up a few hours later?

Just so I've a best guess here before throwing money at parts.
Really appreciate your help here!

Thanks for the info.  Did you change both belts, or just  one of them?  Also I would suspect that the Variator pulley between the two belts is not doing it's job properly which is quite common on these machines.

Inside the Variator pulley there is a couple of tin rings which have little tabs on them to cover the plastic ramps which push the pulley halves together and keep the belts tight.  These little tabs tend to break off. Quite often when the spinning the Variator by hand with the belts removed these broken tabs fall out.

Variator pulley Part number 411001 (I will warn you though, they are not cheap).

All this is assuming you've changed both belts, and that the gearbox is good and clutch inside it isn't slipping.