megane 225 cambelt

[Moggy]

anyone ever done one?


got all the tools and stuff to do ours - god it looks horrible!

anyway

renault say you have to change the nuts on the cam pulleys as you have to release them to tension the belt up??????:confused:

anyone ever done that, or do you just do it like the clio f4r engine and lock it down, change the belt, roller and tensioner, rotate, check the tension and go home?

cheers

ME

[D4WNO]

Oi Moggy, your membershp has run out....sort it aaaarrrrrt :p

[Andrew Cooke]

I think you're supposed to replace the bolts on the F4R too, but whatever...:laugh:

[James5]

I think you're supposed to replace the bolts on the F4R too, but whatever...:laugh:


Only if they have stretched otherwise re-use them.

[Andrew Cooke]

Only if they have stretched otherwise re-use them.

how do you tell if a stretch bolt has been stretched?

[Matt Cole]

how do you tell if a stretch bolt has been stretched?

I would have thought applying the max torque to the bolts would have indeed 'stretched' them?

[Spooky]

I thought the bolts would stretch if they were over tightened, too much torque ?

[James5]

how do you tell if a stretch bolt has been stretched?


If a stretch bolt has already been used once it has already been stretched to the correct setting for it's application as a stretch bolt is designed to be stretched this re-using would more than likely over stretch it thus it will not hold the same torque (tension) it will stretch more looseing tension and possibly fracture ??? Just guessing here LOL


Prob a stretch gauge available to measure??

[Spooky]

You can measure stretched bolts with a vernier and you will find a difference.

If the bolt is out of spec, replace it.

Did it a few times at Honda.

The torque for a bolt is specified to ensure the part/bolt/nut is within operating range and will not affect the quality and operation of the parts involved.

With the cams on the VTEC engine, I've replaced them everytime...and that was on engines that were hours old.

[Spooky]

All this talk of stretching is getting me excited...I actually know the physics behind it...can I explain what happens to the metal in maths...? :D :ashamed:

[Sparkie]

All this talk of stretching is getting me excited...I actually know the physics behind it...can I explain what happens to the metal in maths...? :D :ashamed:

is it that the crystals/grains of the metal are being deformed? ;)

[Andrew Cooke]

ok,

so no need to replace the bolt unless it's stretched

if you've used it it will have stretched, so you'll need to replace it :laugh:

[Moggy]

ok ok ok so If they have grown up and dropped! ;) I have to change them

so has anyone done one?

[Ashy]

I thought the bolts would stretch if they were over tightened, too much torque ?

Normaly stretch bolts will have a torque setting + angle. So it'll be 60nm + 90 degrees etc.