Replacing Crank Pulley

[Daverb]

I'd like to fit a light weight pulley.

From searching it sounds it can be accessed from the wheel arch and removed with a air gun.

Timing shouldn't be affected as the belt is sitting on a sprocket on the other side of the crank pulley.

Is it easy enough to do up to the correct torque again? Can the engine just be left in gear or does the flywheel need locked?

 

[Chrisgti6]

I believe you can't just undo the pulley as the sprocket behind isn't keyed so is only held in place by the torque of the bolt. Ideally the timing needs locking into position first with the timing tools.

i could be wrong, I'm sure someone will be along to say

 

[Stephenvenning]

The clio 197 cam sprocket is keyed, you'll have to loosen off the tensioner, take the belt off and then undo the wheel. I'd just change the aux belt while your at it.

 

[Kazumz]

Mark the Cam by taking off the cam cover, undo the pulley, check the timing on the fly and cam position, readjust if moved, your fly is already marked. No need to take entire belt off, just undo tensioner.

Not hard.

 

[Daverb]

Not sure i really understand this. Sure its not that hard and its just that i havent seen it but if the belt is tight and under tension i cant see how the timing is going to move. The belt will be tight on the cog underneath the pulley and can't move / jump a tooth.

 

[Stephenvenning]

Not sure i really understand this. Sure its not that hard and its just that i havent seen it but if the belt is tight and under tension i cant see how the timing is going to move. The belt will be tight on the cog underneath the pulley and can't move / jump a tooth.

What happens is if the AUX belt fails it usually falls off the crank pulley and goes inboard on the timing belt causing that to slip of jam.

 

[Raptor6767]

 

[Foxspeed]

that all assumes the crank sprocket doesn't move with the cam sprockets once the pulley is removed....

 

[strell]

Bump. I have the crank pulley.

Do I just need to undo it and do it back up. Or is it as complex as some have said?

 

[RSRowe]

Yep. Remove belt, undo pulley, fit your new pulley, put belt back on.

You’re meant to use a new bolt as they’re a stretch bolt, but I never bothered when I did my cam belt.

 

[RSRowe]

Don’t forget to tighten to 40nm + 110 degrees too.
Don’t under/over do it

 

[strell]

Thanks. Will have to guess the angle somewhat

 

[RSRowe]

Mark the flat on the bolt, then go 2 flats tighter…. That’s 120 degrees

There’s a 10 degree +/- tolerance on the specs

 

[strell]

Mark the flat on the bolt, then go 2 flats tighter…. That’s 120 degrees

There’s a 10 degree +/- tolerance on the specs

Quick maths. I like it.

Can stop just short of the 2 and be golden.

As a side question I have never quite understood why some bolts are X torques then X degrees. Does anyone know why? And why they can’t just be Y torques?

 

[RSRowe]

It’s just a different way of torquing things. Completely normal.

Torquing to a degree is generally more accurate as it takes out any frictional interference which you get when you tighten just on load.

 

[strell]

I must be being stupid. How do you stop it from spinning when you try and undo it?

 

[RSRowe]

Put the car in gear (and hold the brakes if it’s jacked up with the wheels off)

 

[strell]

Put the car in gear (and hold the brakes if it’s jacked up with the wheels off)

I did have it in gear and it was still spinning.

Maybe I needed it in reverse or is the LSD going to be the issue?

On my own at the minute. Getting someone to hold the brakes isn’t an option.

 

[RSRowe]

I don’t know what else to say to you.

You need it in gear with the brakes applied. That’s the simplest way of doing it, unless you happen to have the Renault crank locking tool or can access the flywheel

 

[strell]

I don’t know what else to say to you.

You need it in gear with the brakes applied. That’s the simplest way of doing it, unless you happen to have the Renault crank locking tool or can access the flywheel

Fair enough. I’ll see if I can get a stick of something to press the brake.

Or I can put a screwdriver in the disc veins to stop it spinning