ok so starter the van the weekend to turn it around in the garage the new to me engine that I've just installed sounded like a bag of spanners the only thing that had changed since the first run was that i had tighten the fan belt as it was loose. the bully ring on the fan felt loose so i took of the fan and found this all the bolts were loose one had lost its nut and washer and the ring was moving in and out about 4/5mm i initially thought new nut and washer tighten it up away i go but after a bit of research it seams they are factory balanced, so my question is can they be rebalanced if so how or is it better to get another one but i won't know if that has been stripped apart and is out of balance ?
If you can not find any better solution: You would do best to replace all the nuts and bolts with identical new ones. As then they will not add any more imbalance.
Have a look on the rim they usually have crimped weights in , but I would think they are balanced as a complete unit I have a complete spare if it looks toast
Did you find the nut and washer? Put it back together like it was almost tight. Get a square like carpenters use, put the long bit right across the fan, short bit over edge of pully/fan. Try it in all directions, gradually nudge the pulley until the pully and fan are concentric. You can get it fairly accurately centralised like that.
I'd start again then, £25 0n ebay for the whole thing every time I look. I have a spare I got that way.
They are balanced as an assembly. You have three choices: 1. Fit new bolts, centre the pulley on the fan and hope it’s in balance – that’s what I would do/have done. Index the pulley so the balance weights are at least roughly in the right place. 2. Buy a used one and hope it hasn’t been tampered with and it’s in balance. 3. Fit new bolts, centre the pulley on the fan and have it balanced – probably the most expensive.
