Go to manuals library and download the Masport " Rotary Mowers Service Manual "
Lots of nice detailed pictures of servicing the various self propelled .
OK
I am a Victa Specialist and the shop up the road is a Masport dealer so I don't see very many of them.
I will have a poke around and see what I can find.
However I will need some more information
What engine does it have and what is the model number on the tag at the rear. normally in front of the catcher flap
Is it single speed, variable speed or gears and is it front or rear wheel drive
Thank you so much. Really appreciate that. I will send some photos as well. It is self propelled. It has a Honda 160 engine. Rear wheel drive. That much I know. It is 550 ST Series 19. I will try and up load photos later. Thank you so much. Sarah.
The single speed rear drive should have an idler pulley that is mounted in a slot that you slide in& out to tension the belt.
The variable pulley has a spring but some times the sliding member sticks so the belt falls off when you try to increase the speed.
The swiveling gearbox style also has a tension spring
This is what I have. A swivel gear box and this belt system attached to it. There seems no way of adjusting the tension here. There are to springs put the pulley does not move backwards or at all so I cannot see how the belt can be tension here. ???
There should be a slot on the side of the mower where the bearing housings is bolted on.
That is where the belt on the internally clutched box you have would be tensioned.
You should have loosened them to put the new belt on
If you just slipped the new belt on then it is too long.
This assumes the drive cable joins the lever in the same hole as the larger spring.
None of those numbers do me any good on the Masport dealers portal
So back to square 1
is it a single ( fixed speed ) or a variable speed transmission
Roughly how old is it ?
The adjusting slot is on the GEARBOX mount either under the mower or behind the left wheel.
Otherwise there is some adjustment on the cable which moves to box to tighten the belt.
Take the spark plug out and stand the mower up on its front wheels so you can see the entire transmission.
There has to be something there to prevent the transmission rotating when you engage the drive otherwise the transmission will cant forward enough to throw the belt off .
According to what I can find it is either an anchor plate on the left side of the gearbox which has a slot in it to adjust the the position of the gearbox and thus the tension in the belt.
Another system is a stud that passes through the bearing retainer and sits in a slot
The third is the bearing retainers themselves being able to pivot on a mounting bolt.
To get at the last two you have to remove the left wheel because you can not see them while the backing plate is in position.
I have gone back through all of the available material from 2000 till now and the above are the only systems Masport used on domestic mowers
Commercials have a single tension pulley which is mounted in a slot through the top of the mower or a set of double pulleys making a tension clutch .
The variable speed transmissions use the actual cable as the anchor for the transmission because the cable rotates the entire transmission in order to vary the tension in the belt and thus change the speed.
Commercial vari speeds used a variable pitch pulley
