Guys, Today I started to knock down my MRS3 to replace the timing belt tomorrow. I´ve got an english manual (funny, I´m German ;-)) and followed all instructions with removing the parts, so far no problem. Now I found that the crankshaft accessories pulley (what drives the alternator and the AC) has to be removed, clearly to get access to the timing belt. Now in the manual is envisaged that the crank pulley itself has to be replaced - sounds strange to me. Of course the fixing bolt has to, because it´s a streching bolt what has to be tightened with rotation angle. But the pulley itself? I don`t remember, the car is downstairs, if the pulley is an torsional damper or not, but just by removing and refitting it shouldn´t be damaged in any way. Or is it an precaution by Renault just on the Megane RS? If somebody is Renault mechanics or has considerably experiences, please tell me your thoughts. Thanks a lot.
The Pulley is a vibration damper, but i would say if the rubber isn't breaking out it will be good to go again, mine is on 115k miles and went back on. You need to remove the pulley to get the belt off and the new one on, there isn't enough room else. You should get a new bolt with the belt kit, so you might as well use it.
I change my belt just today, but I don´t replaced the pulley and bolt neither. It isn´t in the box kit in fact. Normally, in Dayco kits, the bolt is usually if it necessary to change.
Thanks for your quick response....I thought so as well, just looked around in the web about other info, some guys told about broken pulleys not only at the Megane, as well on Lagunas, the pulley is on all 2 Liters the same. Of course i use a new bolt and tighten it with rotation angle. Probably I order a new one from Metzger (well reputed in Germany for only 75 €) to get a clean conscience. My car has run now 85k, if it fails with 130k, it´s a mess as well….So I´m going to use Corona break to wait for the pulley after Easter….happy Holidays !
I would advice you to replace the bolt. Every rotation angle bolt has to be replaced after removing. There are a lot of torsional vibrations on it, don´t underestimate it. I´m engine engineer, I know about I tell...and tight it properly not with the impact driver, but rather with rotation angle as envisaged by Renault.
Do you want a German manual? Just send me your email over PN Where are you from? @manugtt it's a expansion screw. Visible at the "I" written down at the end so as I learn it at school it's really a must to renew it because if it's over his plastic expansion ratio it's too log (not meausure possible) and can't make his pressure / force it needs to make. But it doesn't need to break, it's just possible. The bolt holds the Pulley, the chain wheel behind and also the oil pump wheel, doesn't want to scary you but if it's too loose or will get it doesn't would be nice But great job! I was very scary at my first timing belt job at this car
Ok! I´ll order a new one. I undertand that you say, I´m not engineer but have over 20 years working on cars. In many cars the factorys or the belt companys warning you to replace the bolt, but not in others. Maybe I´m lucky, but I fit the same bolt many times and never had a problem. Anyway, I´ll replace mine, just in case!! Thanks for yours advices mans!!
Nice, you are much more experienced than me I think it would also hold but it's more for the conscience
Yes man, I´ll do same for same reason! Maybe I have any experience, but make mistakes too!! The good thing is to learn about these. The theory, like yours, is very important!
Guys, I´m close to Stuttgart. About the bolts: If you are torquing a bolt, it´s much more exakt to use Rotation angle rather than torque readings. If you tighten a bolt, 85-90% are applied for the friction to move the bolt within the thread. The rest of 10% are useful to get the bolt stretched what makes clamping force. If you usr torque readings, the envisaged clamping Forces are massivly depending on the friction figures of your threads and the friction of the head contact area of your bolt. So the clamping force is gamble. To overcome this Problem, in the late 80s engineers developped the rotation angle method. First you apply a small amount of torque what doesn´t make a big difference in fricton due to the low loads. TZhen you apply a rotation angle what is calculated to stretch the bolt. If you strech a steel part (not only a bolt), first it stays elastic and is like a spring, gets back to the lenght it had before once you release it. If you stretch it more, it starts to plasticate, it keeps it´s Distorsion. If you stretch steel more than elastic , further to plastificate it, the loads to elongate it is almost constant. That means that a bolt, what starts to stretch, keeps it´s clamping force constant within a very small range. For instance on cylinder heads, it´s a very nice method to get all clamings of 10 bolts (or nuts) very equal to reduce warping of the cylinders to an very small amount. If bolts are considered to use the rotation angle torqueing, after every release and retorquing the bolt should be measured the lenght. Soemtimes, it´s allowed to use bolts 3 times. But due to the fact that the measuring of bolts is a bit tricky, most OEMs are advising to scrap them and uns new ones due to the inexpensive costs. If you are involved in racing, probably you know ARP bolts, it´s possible to measure their length and judge after rebuilding if you can use them again or not. But on a bolt what Costs some cent, it´s not worth the expense. Don´t reuse them. Hoping that helps you to understand how rotation angles are making sense..... Furthermore, look at the Pictures to my vibration damper of my MRS3. I´m pretty sure that it was a good idea to replace it....
I can´t say if my crank pulley would cause a problem or not, I`m not able to look inside the rubber ring. But I was a bit worried about the appearence after 85k km. In thze internet, some guys had troubles with the pulleys, they are all the same for 2 Litre engines. If it brakes, some fractions will get into the timing belt what causes big engine failures. Usually, a crank pulley is a lifetime part and should make 250k kms…..disappointing. I admit that i ride my MRS sometimes hard and did some slaloms with going some 100 m touching the rev limiter. But compared to some Nürburgring guys it´s a ridiculous stress. Anyway, I would advice all pedal to the metal-guys to check their pulleys frequently. Some rumours said that the pulleys costs at Renault about 265 €, I didn´t ask as yet. In Germany, Metzger is a well reputed company what supplies for instance control arms, wheel bearings, steering parts, brakes, a lot of aftermarket parts however. very good quality. I´ve ordered the pulley from them, the charge is 75 €. Hope that it´s as I expect from them.
Nice lesson man! I appreciate, really. Today I´d looking for a new bolt in my garage, but don´t have lucky. I order new one to my usual parts provider. Thanks again!
