Kubota W821-pro repair help

[hazza26]

Couple of problems.. I've managed to snag the top end of the mower deck control cable and it's snapped. Also the propulsion drive takes a bit forward movement before it kicks in, which I assume is a worn out belt.

This has happened at the worst time of year to get it professionally serviced so I'm trying to work out if I can replace these myself. Can't find a service manual online anywhere.

Anyone have any suggestions? I know these are essentially rebadged Kaaz / Denarm / Lawnflite / Honda mowers but I'm not sure of the equivalent model numbers.

I'm done oil change / air filter / blade service stuff but not sure if these are within the expertise level of a non-pro!

Any help much appreciated

[Mick]

Hi hazza26, and welcome to TGMF

I think you'll find it's shaft drive from engine to gearbox so no belt to change.  Sounds like the dog clutch in the gearbox isn't engaging until you help it forward.  This is ether worn dogs, badly adjusted or stiff clutch cable. or the cutch arm on the gearbox has cracked and slipped around on it's splines. Normally it would make a rattling noise while it tries to engage. 

The other thing which is quite common with these is the needle bearings on the gearbox output shaft can seize up making rollers jam. 

[hazza26]

Thank you Mick! Well all that stuff is way over my head so I think a long wait at the mower service shop is my only option 

[hazza26]

Hey Mick, hope you're still here and well! Just getting back onto this after my first mow of the year.

I replaced the blade cable and spoke to a service engineer about the drive last year.. he rightly pointed out the labour to do this is going to cost more than the value of the mower. So I'm feeling brave and up for giving it a crack myself. I found a gearbox repair video guide for what I think is a like-for-like machine:
https://youtu.be/an73-HJb7nc?si=RWtEPNMFkhdcxoG4

I just wanted to check what my diagnostic process should look like to ensure I'm fixing the correct bit. No rattling noise while it engages so can I rule out the clutch arm? So next stop try tightening the drive cable and check if that makes a difference? If that's ok how do I know whether it's the dog clutch or needle bearings? Is it just take it all apart and have a look? I think I can recognise worn dogs but what about seized up needle bearings?

My repair experience is only oil change / new blade / new blade cable so far, so if this is likely too complicated for a newbie like me then do say!

Any help much appreciated 

Many thanks
Harry

[Mick]

Hi Harry.

The labour cost isn't normally too bad to be honest, it's usually the cost of the parts that kills the job.  Providing it all comes apart without issue it's not a bad job to do.

You say there's no jumping or rattling when you engage the drive?  I would remove the plastic pto cover and check the drive shaft, and while in there take a look at the arm to make sure it's not cracked or slipped around on the selector shaft.  Make sure the rollers can freewheel when not in drive, if not then the two needle bearings are probably seized.

If the dogs are worn you'd normally get rattling or jumping when you engage the drive.
If needle bearings are seized it will make the rollers stiff to turn or not turn at all.

[hazza26]

Hey Mick, ok thanks, that's interesting. No there's definitely no rattling or jumping. I engage the drive, no noise, have to give it push for it to start moving, then it regularly stops and I have to push to get it moving again. Wouldn't say it feels hard to push without the drive on - well expected hard for something weighing 70kg. Btw it gets bogged down in the grass much more than on concrete.

Ok great I'll follow your instructions and have a dig next weekend. Thanks so much!

Cheers
Harry