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Quick crankshaft pulley question

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31 Oct 2024 10:44 #258115 by Rogerzilla
I don't want to DIY for various reasons - the garage is worried because Autodata or whatever they use says a special tool is required to remove the pulley.

1. Is this just a locking tool to stop it turning while the bolt is being unscrewed, in which case there are various standard techniques like an air gun, a sprag through one of the slots, etc?

2. Does the pulley come off easily by hand once the bolt is out?

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31 Oct 2024 13:17 #258117 by Busta
Yes the special tool is just a long bar with a couple of holes in it to hold the pulley. A proper impact driver will undo the nut, or there are other methods that don't require any special tools. Once the bolt is out the pulley comes off very easily.

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31 Oct 2024 19:55 - 31 Oct 2024 21:06 #258121 by Rogerzilla
Thanks, so an impact driver on its own should Just Work and, if not, jam the pulley with something?  Should be standard garage techniques, then.

There is the starter motor technique endorsed by Scotty Kilmer et al but AIUI there is a small risk of stripping the ring gear teeth or the starter pinion.

Also, it's an auto - what position should the transmission be in?  P or N?  I imagine P could break the parking pawl?
Last edit: 31 Oct 2024 21:06 by Rogerzilla.

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31 Oct 2024 21:39 #258122 by Busta
Yes a decent size impact driver will do it. I've always done them with the starter motor. An 18" breaker bar rests nicely against the NS inner wing to hold the bolt, then a quick flick of the key does the magic.
It doesn't matter what position the auto box is in, the torque converter will prevent you from turning the transmission. Manual transmissions are best in a high gear, 4wd with someone pressing the brakes, but I've found the clutch slips before the bolt will come loose.

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01 Nov 2024 00:04 - 01 Nov 2024 00:06 #258123 by facade
With an auto they will need to make a locking bar to tighten it up again.

I made one from a piece of old desk I had knocking around, I can't remember the hole centres, around 75mm I think (but they can measure off the new one, the bolts are standard metric threads, probably M8), my bar needed notching so it goes round the PAS bracket.

Nothing on Earth would undo the bolt on mine, it was rusted solid, so after a couple of evenings of futility with rattle guns and scaffold poles, I simply sliced the flange off in pieces with a grinder (the crank nose is about 3mm short of the pulley) and undid it with my fingers!

Just let the garage worry about it.



 

If it suddenly breaks, go back to the last thing that you did before it broke and start looking there :)
Last edit: 01 Nov 2024 00:06 by facade.

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01 Nov 2024 07:23 #258126 by Rogerzilla
That was my idea (let the garage worry about it) but the last two garages that have worked on it have been hopeless, leaving it with slipping belts and coolant leaks, and it's hard to find a proper mechanic.  I don't think many have the nous to work around a problem if they don't have a special tool.  The Suzuki tool, which has dogs to engage the four pulley slots, seems to be unobtainium anyway.

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01 Nov 2024 07:55 #258127 by yakuza
 
Cant make miracles happen, but it is very good.

Norway 2005 Jimny M16A VVT, 235 BFG MT, 2" Trailmaster, ARB rear lck, 17%/87% high/low gears.

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01 Nov 2024 09:40 - 01 Nov 2024 09:42 #258128 by DrRobin
I made a special tool similar to the one Facade made, you can see it in action here.

www.bigjimny.com/index.php/forum/6-jimny...ust-fell-off?start=0

The tool is about 400mm long, made from 4mm sheet steel and was an old antenna bracket I designed for work.

 

When I first loosened the bolt I had to use a longer breaker bar, 1m long but the bolt came out.

Robin

2020 blue SZ5 (one of the last to be registered in the UK)
Ex 2011 Blue Jimny SZ4
Northumberland Jimny Blog

Last edit: 01 Nov 2024 09:42 by DrRobin.
The following user(s) said Thank You: gv42

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01 Nov 2024 09:44 #258129 by facade

That was my idea (let the garage worry about it) but the last two garages that have worked on it have been hopeless, leaving it with slipping belts and coolant leaks, and it's hard to find a proper mechanic.  I don't think many have the nous to work around a problem if they don't have a special tool.  The Suzuki tool, which has dogs to engage the four pulley slots, seems to be unobtainium anyway.
 
I thought the tool clamped flat against the pulley inner rim using the two threaded holes like the one I knocked up, then it relies on friction between the surfaces rather than the bending of the bolts.

   

Everyone else here had no trouble either bumping the bolt undone with the starter, or rattle-gunning it off, it was just mine that was so badly corroded.
I tried all the Magic Fluids I had, diesel, GT-85 WD-40, Plus-gas, and even got the torch to it and made it glow red- so I ended up replacing the seal too, as I thought it might have melted. I spent the best part of a week on it with leaving the Magic Fluids to soak in and re-applying.

Tbh, if the garage can't do straight forward jobs properly, I'd stop using them.






 

If it suddenly breaks, go back to the last thing that you did before it broke and start looking there :)

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01 Nov 2024 12:20 #258131 by mlines
I had to do what Facade did. Grind off the flange faces around the bolt to reduce the area that was corroded together so the bolt can be undone.

A further point to note. The pulley is stopped from rotating on the shaft by a Woodruff key. This sits in a keyway on the crankshaft and is shared between the pulley and the timing chain sprocket. I have had a number of customers destroy the Woodruff key (not particularly a disaster) or more seriously damage the crankshaff key and sprocket.

Martin

2003 M13 early KAP build.
3" Trailmaster lift with 1.5 Spacers on front
Customised winch bumper and roll cage
235/85R16 Maxxis Bighorns on 16" Rims, 4:1 Rocklobster, Rear ARB locker and on-board air
Corrected arms all-round, rear disks, Recaro seats and harnesses

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01 Nov 2024 16:18 #258133 by facade

 <snip>

A further point to note. The pulley is stopped from rotating on the shaft by a Woodruff key. This sits in a keyway on the crankshaft and is shared between the pulley and the timing chain sprocket. I have had a number of customers destroy the Woodruff key (not particularly a disaster) or more seriously damage the crankshaff key and sprocket.
 
Was that through not fully tightening the pulley? - 150Nm, you need that locking tool to get that easily.



I can't imagine how else you could damage the key except by fretting because of a loose pulley.

If it suddenly breaks, go back to the last thing that you did before it broke and start looking there :)

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01 Nov 2024 16:52 - 01 Nov 2024 16:56 #258134 by DrRobin
The woodruff probably gets damaged using the 'starter motor' technique, as the rotational force is through the shaft (and key) to the bolt and it's probably the jolt or repeated jolt which damages the key.

At least using a tool like the one you and me made the force is applied direct to the pulley, so if the bolt is stuck on the pulley it's more direct and less likely to bend anything.

When I did mine a few years ago we had a lot more force than 150nm on it, we had a 1m breaker bar (3/4" drive), with a short extension and a 80Kg bloke on the end, that's probably nearer 800nm.

Robin

2020 blue SZ5 (one of the last to be registered in the UK)
Ex 2011 Blue Jimny SZ4
Northumberland Jimny Blog

Last edit: 01 Nov 2024 16:56 by DrRobin.

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