Repairs toro gear issue

Hi please can anyone assist, bear with me on my description I hope it makes sense
I own a Toro 212-5sb s/n 32-12B501?..10439?
It has been running perfectly up until last night when I removed serviced and replaced the drive pulleys underneath, I also removed and serviced the brake on the gearbox
Now I find that when the engine is running and I select a gear (slips into gear smooth)? will drive for a meter or two ?.stop to select another gear ?but it has stuck in that gear , it will not let me select any gear ?the only way I can release the gears is by switching off the engine ?this happens in all gears no matter which I select first forward or reverse ?..now I see there are wires leading from my gearbox ,,,this seems to be a safety device that only allows me to start the engine in neutral (is that correct)?lso is there a balance in setting up the break / clutch ?..have I done anything by my servicing ?
Please any ideas ?..p.s what does the SB part of the serial number mean
Neil
:smile:

Check to see if you have routed the belt correctly. Sounds like the belts may be on the outside of a belt guide or the wrong side of the idler pulley.

Cheers Rivets for replying,
I was fortunate to find a maintenance guide today , but one thing i did realize form the diagrams was that i have put the belt guide from the fixed pulley (the one by the engine) on the wrong side ...i noticed that i have put mine on the chassis side not on the inboard side , as i in work at the moment i cannot try to rectify it , i will do when i get home .......but would something that simple upset the balance of the drive ,
neil
:smile:

Big time, hate to say it, but it is the most common mistake when replacing belts.

Cheers Rivets,
I hope it is that simple ............to be continued...lol........i will post on how i get on later
:smile:

Hi , it was as simple as a belt guide fitted the worng way around

Thanks for all your help
Neil:biggrin:

Glad to be of assistance.