You are correct the smoking is happening because the belt is slipping on the pulley
Slip the belt off and have a look at the shinny polished region where the belt is running
It should only be the sides , if the root of the V is polished then that pulley is worn out
I can not find an IPL for your exact mower but being that old you will have substantial wear in the deck mounting system
The big springs that pull the deck back are the ones that control the tension on the deck pulleys
They are a bugger to remove and do tend to cut groves into mounting holes over time so loose some more tension there
All this assumes that without the deck belt on the blades spin freely .
Thank you for your reply and sorry for the delay in responding... got busy with life so didnt get round to sorting the mower as quickly as i would have liked. Anyway luck has been on my side with this mower. i bought a new belt and tension spring got them fitted... finally i now have a fully functioning yardman yay!
For removing the old and placing the new spring i got a length of wire made a loop in both ends, put one end around the hook on the spring to the rear of the mower and attached the other loop to a ratchet strap attatched to my quad bike.
Tightened the ratchet until i could gentley move the spring hook from the belt then released the tension on the ratchet strap.
putting the new spring on was the reverse... us girls have to use our brains as our strength isnt our strong point.
All in all i'm happy to say what started off as a potential nightmare buy from a farm auction has actually turned into a frustrating but nice little purchase, yes it was a massive gamble and fantastic learning curve .i have learned so much from you all on here, and i cannot thank the ones who responded to all my stupid questions enough for taking the time to give thoughtful and informative responses. (only had one negative response of buy at an auction what d ya expect!)
I am sure as time goes by i will be back for more advice.
However right feeling pretty proud of myself for being able to sort it all out and loved learning new things in the process.
thanks again guys and never stop doing what you are doing the knowledge you guys have is teaching future generations to keep the fix rather than throw mentality.
all the best.
LuggyNuts