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As you can see in the picture the pulley wheel has suffered a failure and I need to replace it, however it’s got me stumped.
The broken pulley with the red arrow, and the the pulley above it (green arrow) sit directly below the engine and are driven directly from it. The green arrow belt/pulley takes drive to the wheels via the yellow marked pulleys.
When I turn the red nut the broken pulley doesn’t rotate but the green does.
I (think) need to stop the green pulley from moving so I can actually undo the red bolt but I can’t do this, there’s no room to wedge anything in there and i can’t just hold the belt (to the yellow pulleys) as that will just damage it. I’m stuck.
Oh I’ve undone the blue ‘x’ nuts but that’s done sweet fa. It’s a big ride-on mower and I can only access these parts from underneath
Edit. I’m now off for 2 days so won’t attempt any suggestions until Saturday
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just to confuse things.... it's not left handed is it?
do the wheels turn when you turn the nut? if so you could try locking the wheels instead of the pulley
That looks like an oil filter in the top right corner of the image. Drop that off, run without oil. Should seize up tight enough to give some resistance to work against.
Possibly (there are others on this machine), but either way I turn it at the moment the green one still moves. No the wheels don’t move
Heh thanks dashed
I did a quick edit, if it drives the wheels try locking them instead of the pulkey
Sadly it doesn’t drive the wheels when switched off
The problem pulley is the main drive for the cutting deck, I’ve turned it all on, engaged the deck then switched off (leaving deck engaged) to see if that does the trick, which it doesn’t
Google "[mower model name] pulley removal," there will probably be a YouTube video on it.
More helpfully, can you engage the clutch / put it in gear to lock things up? Or engage the blades if it's drive for the blades not wheels.
Impact gun!
First thing I tried Cougar, unfortunately it’s quite a small Italian brand so there’s no ‘how to’s’ anywhere, not even for the simple stuff.... I’ve thought about actually doing some videos
I can call out the local service place to come and sort it, but I’d rather fix myself
Impact gun would probably jumpstart the engine 😂
Looks like a centrifugal clutch.
To get the red bolt undone either get you spanner on there and turn the engine over until you get compression the whack the other end of the spanner to shock it or jam something in by the green arrow to stop it turning and do the same.
The clutch will have an internal keyway on the clutch and shaft to lock the two together so you may need a 2 or 3 legged puller to get it off the shaft. Or if you're lucky you may just be able to put the bolt half back in the hole an give it a pisser while levering the clutch away from the base with a screwdriver.
I’ve tried wedging the green one, but there’s chuff all room and a flat blade screw driver doesn’t do anything/hold it
I’m working on my own at the moment, and the mower needs some sat on it to start up, plus I’m a bit nervous of being under that, I like my fingers.
I do think you’re right though Stu, but sounds like I’m best calling in the pros
I’ve ordered the part, you can’t just get the pulley (that’s broken) it’s basically everything you can see ..... And i have to wait for it to come from Italy
My first ever job was a mower mechanic.
Belt and pulley systems were always a pain in the ass.
Just remembered how i used to get centrifugal clutch off rideons the easy way.
Remove spark plug, screw in piston stop, turn drive shaft slowly until the piston contacts it and locks up. Then undo the bolt.
Not much use to you though if you've not got a piston stop.
Edit
I’ve ordered the part, you can’t just get the pulley (that’s broken) it’s basically everything you can see
You'd struggle to get a centrifugal clutch back together again off the machine. There's a chuffing great spring in the middle that'll try and take your eye out.😲
Shame you’ve got a busted shoulder or I’d be asking you to pop by and crawl underneath 😂 did you ever work on Grillo’s?
Yeah I think I’ve reached the limit of my mechanical capabilities
Edit for your edit. Yup, I’m definitely admitting defeat and getting the pros in
can you tie a ratchet strap across the upper drive belt to lock the green pulley (think across two sides of a triangle)? this might give you enough purchase to lean against the bolt to undo it.
personally I'd be getting an impact driver in there though.
Just like a chainsaw.
Pop out the spark plug, spin the pulley so the piston is at the bottom of the stroke. Look down the newly formed hole.
Drop in shoe lace, bit of starter cord and leave a tail out the hole.
Turn the pulley to jam the piston against the cord and voila makeshift piston stop.
Undo bolt and repair at your leisure then pull cord out.
Google “[Briggs & Stratton mower model name]
Now that I can do* Jamie
*maybe, I’ll have a look on Saturday
Honestly, you had me at 'bloody great spring,' I'd be getting someone else to do it. Springs are subtle and quick to anger.
Yup, seeing as it’s all at eye level when I’ve crawled under there I think it’s for the best
Jamie has it. Much safer then piston stops which can hole the piston top. With a chainsaw or other 2 stroke just be careful not to get a bit of rope wedged out the exhaust. 6 or 8mm static climbing/accessory cord is very good for this purpose.
To add wondered if you can get vicegrips locked onto the bust pulley and wedge against something to stop it turning?
is the nut stationary when started up (which it might be with a centrifugal clutch)? If so you could start it, whack a socket on a long extension bar onto the end, and give it some gas until the nut starts to turn (thus undoing itself)?
Whatever you do, I assume you've taken the plug lead off.