OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Scotty 45 Chain advice

Gday,

I've just stumbled on this site. I've got an old 'Scotty' that I assume is a 45. I've seen someone else has a 'blue' one also. The queries I've got :
1. as you'll see from the pics below the front chain has a lot of play in it, to the point it now jumps off. If I was to get a link removed it then wouldn't join up (from my judgement anyway) Is it simply easier to simply purchase a new chain and if so does someone with a manual have the part number I'd require ?
2. When the above chain jumped off, it then busted a link on chain behind it, see pics - top cog, chain is resting there. Can these links be repaired or easier for a new chain ? if repair then a part number would be great





and some pics of the whole unit





Thanks in advance for any advice
cheers
Leigh

Hi Leigh, the first thing you should try is to completely remove the damaged link,(drill it out if necessary) and buy a removable link to replace it; (the same as the one used to remove the chain) next to the broken one in your pic....Next,loosen the nut on the black plastic chain tensioner and slide it down as far as it will go in it's slot.
Replace the chain and it should join up correctly for you.
Retension it with the slider to retain about a half an inch of slack and re-tighten the nut.
Down the track, you really should buy a new chain as this one seems to have stretched quite a bit.

Thanks Deejay, I ended up puchasing new chains and some other parts while I was at it. I'd rather get it right the first time than buying a partial fix

cheers
Leigh

Stretched chains ruin sprockets - because they are out of pitch, they put all of the load on one sprocket tooth. You can usually see the wear by comparing how pointed the tips of the sprocket teeth are, alongside a new one. If your sprocket's teeth are very pointed, or have a long taper instead of widening rapidly from the tips, they are done for. Really terminal wear results in the tips of the teeth being undercut so far that they break off. Putting a new chain on a worn-out sprocket tends to ruin the new chain fairly quickly - it puts all of the load on one link instead of spreading it around the sprocket. If the sprockets are worn, it's much better to replace them simultaneously with the chain.

Meanwhile I hope you followed Darryl's instructions on tensioning your chain. The old front one looks rusty - keep your chains properly oiled if you want them to last. I like chainsaw bar oil for the job. Rusty chains have a very high wear rate (and then they ruin your sprockets too).

Hi grumpy, great advice there mate, I just went back and had a look at the engine drive sprocket in the pic....It's exactly as you describe, pointy teeth!!
That sprocket can be difficult to remove; I had cause to replace my engine drive shaft and bearing and I had to buy a gear puller to remove it. (Taper shaft and half-moon key)
The gear puller comes in handy when I have to remove the front sprocket for cylinder (reel) removal for sharpening.

As this thread has not been in use for some years, I will now close it.