How to fit new drive belt to Suffolk Punch Electric mower

[brissle]

Can anyone please advise?
The toothed drive belt has broken on my Suffolk Punch Classic Electric 30 mower. this is not the easily replaced outside drive belt but the one which motor drive to the main drive shaft which operates the cutting cylinder.
i cannot see how to dismantle the upper shaft enough to enable me to slip the new belt into place. I would appreciate any advice. I have attached 3 photos to show the location of the belt.
Many thanks

 

[HERTS P&D]

By the looks of it, you would need to strip it down from the outside, removing the large nut and pully, then screws, hoping that it would pull out giving you room to slip on the drive belt on the other side.

Anyway John will be along soon.

Andy

 

[brissle]

I've tried that - the shaft won't pull through the hole, so i would have to remove the entire outer housing.
Maybe that's what I have to do, but It seems a hassle and a big dismantle just to replace the drive belt.

 

[Burnerman]

Allow me to scratch the brain cell, but if you look at the aluminium large gear you can see that the boss has flats on so you can hold it with a spanner while you undo the large pulley nut.
The vee belt is easily slipped off beforehand.
This should allow the black plastic piece behind to come off and I think you can get the belt in then.....I’m thinking of a similar machine to this one though.
John

 

[brissle]

Yes John, I've gone as far as you are describing, but even when I removed the black piece there is a flange on the shaft which prevents it pulling through the hole.
My brain cells are hurting!

 

[brissle]

I've sent emails to a couple of places to see if there's a service handbook for this mower. The basic operating manual doesn't help with maintenance or belt replacement.....

 

[Burnerman]

Unfortunately this one seems anything but obvious and it may be necessary to shift, or at least loosen, the steel cover behind the rubber belt.
As you have removed the top vee pulley and the plastic retainer you should see a bearing - the other side of which is held in a similar retainer on the inboard side of the machine and two screws hold this in place.
The geared large pulley is held onto it's shaft with a roll pin, and the other end of this shaft sits into a housing held by more screws. This assembly is held to the main deck by screws too but I don't think you'll be able to access both of them.
I'm probably talking nonsense here but this seems crazy just to replace a toothed belt but if you slacken all of the screws, maybe there is just enough give
in the assembly for a belt sized gap to appear - maybe with subtle careful leverage?
John

 

[brissle]

Thank you everyone for the suggestions.
In the end it was Burnerman who gave me the clue - all I needed was a gap big enough to slide the belt through.
I achieved that by removing the mounting screws for the entire motor housing and bending it back far enough for a gap to appear at the inner end of the shaft.
Job done and it works fine.
phew! And thanks again.

 

[Burnerman]

We use the same technique when fitting car timing belts.....ignoring the instructions 'under no circumstances twist this belt' of course
Pleased you got things sorted.
John