Thread: The ongoing saga of the ML392

Gumby,
Might be an idea to check your bearings - mine didn't collapse like Bob's but just made a terrible grinding noise and although only one was stuffed I replaced both.
They are the bearings that go into the "idler sprocket" on the left side of the machine (the large sprocket with the smaller sprocket at the front.)
The bearings are the same as those used in skateboards, electric drills etc,

I think I posted some pics etc of them some time back (sept 04) when they 1st went

Thanks BP, will do.

Hi guys,
I've just been fiddling about with the machine and was checking as to why the chain would've come off and noticed that the grub screw on the right hand side drive roller sprocket was loose allowing the sprocket to slide in and out on the shaft very easliy. The left hand one is 'snice n tight' but the right one as loose as buggery. Might be worthwhile checking these too.

Other than that all else seems fine and aligned properly etc.

Thanks Bob & Pete - guess what I'll be doing this afternoon.

"loose as buggery" might be a bit of an exegeration for me but both the in and out feed roller grub screws neede to be snugged up. So worth a check guys.

Bob

Just checked mine & found the grub screw on the infeed sprocket was loose. BUT - when I ran it without the cover, it was obvious that the drive end of the infeed roller was bent. This may explain the 'demented mouse' sound the unit sometimes makes. I hate to think what it's doing to the bush it runs in, although there were no obvious metal filings or play.

However, it seems that there are a problems in this area, and even though it's a 'budget' unit, we should expect it to be up to scratch.

Would it be possible for all you ML392 users out there to check the drive area of your units. First, make sure the grub screws on the small sprockets on the end of the feed rollers are done up tightly. Then run it VERY CAREFULLY with the cover off. do not attempt to touch it while doing this. Watch for a side to side wobble on any of the sprockets. I notice on mine that the large friction drive wheel has a wobble too, but I don't think that's anything major.

If this is a common problem, perhaps we should consider a concerted approach to the company we bought them from for replacement of faulty parts at their expense, even if out of warranty. This should also include return to workshop at their expense if necessary.

Alex,
That was the roller that had the loose grub screw on mine as well - the outfeed drive roller was tight - I have checked alignment and at this stage all appears OK on mine.

Will check mine when I get it together again - one day.

Bob

Picked up the assembly with 2 new bearings fitted on Friday. Installed it back on the machine and gave it a manual checkout by turning the belt by hand. Noticed that the chain was still trying to climb off the large sprocket, but not making it. Decided to run with the motor on. After engaging the cutter blades everything ran well - sooooo quiet compared to before. Can only think that the bearings were gone before I took delivery of the machine. It had never ran this quiet. Then a click sound caused me to turn the ML392 off. Thought the large chain had broken. Not so. The chain was behind the tension roller. Found that the outfeed roller sprocket needed to be moved back towards the body of the machine a little as it was not lined up with everything else. I had not touched this previously other than to tighten the grub screw.

The smaller (rear) chain on my system appears to be very loose. Could remove a complete link. As other owners know, there is no tensioner or other adjustment here. If anyone still has their cover off, could you let me know if your small chain is really loose. I am starting to think that this could be the reason for the chain trying to climb off. Only wish I could move the large sprocket in towards the body.

Bob

Bob, I just had a look at mine and all seems to be OK. The grub screws are tight and all the sprockets seem to be in line. The large chain isn't trying to climb off at all so maybe your was cactus when you got it as you said. The small chain is quite loose though so that is probably normal.

Yep, small chain is loose, but doesn't seem to be doing anything untoward.

There's been so many posts on this machine that I haven't bothered to search back through them but I assume all you guys have a copy of the manual for the AW 106 which is the same machine. It's much better than the one which came with the ML392. If you don't have it, let me know and I'll email one to you. (it's about 2200kb)

All set for beautiful day in paradise. The ML392 - she agoes!

Still not real comfortable about how the small chain is picked up by the large sprocket as it is very close to the chain's outside edge. So what did I do since my last post. Much fiddleing with setup of the rear sprocket mechanism. To cut a long story short, it appears how much you tighten the screw holding the sprocket has a major effect on the setup. I have backed this off a little, then secured its position via the grub screw that is behind everything. I am no mechanical engineer, but I believe that the screw should be a solid shaft with a thread at one end so that the bearing are supported better. I suspect that the grub screw, which was loose, has allowed the screw to unwind thus putting an unacceptable load on the bearings. If this is the case the bearings had either gone before I took delivery or immediately after as I did not notice any change in noise during my use. However, as I mentioned in my last post, relatively speaking, the drive mechanism is much quiter following the installation of the new bearings.

Now to see how long it continues to run without a problem.

Gumby, whilst the Axminster manual is a much better user manual, it uses the same diagrams and doesn't help with information on faults/repairs. We also need a maintenance manual. But we work with what we have.

Bob

Originally Posted by BobR

Gumby, whilst the Axminster manual is a much better user manual, it uses the same diagrams and doesn't help with information on faults/repairs. We also need a maintenance manual. But we work with what we have.

Bob

It has nice picy's too.