[rossb2]

Hi, I’ve got a megane alize 1.6, S reg. On the motorway the battery warning light came on so I assumed the alternator belt had gone so headed to nearest service station. As i got into the service station I got a nice bang and the engine cut out. Looking inside the alternator belt had gone. On later inspection the cam belt is pretty ripped up - it's still there but almost split through. I'm thinking that the alternator belt went but was lodged inside, then managed to damage the cam belt (luckily only when i got to the service station - the engine cut just as i was reversing, possibly this moved the damaged alternator belt?).

A few questions - How did the alternator belt damage the cam belt as the cam belt cover wasn't damaged?

What to do now? I assume the valves could be pretty bent up? So the cam belt would need changing and possibly valves?

I’ve put the car in gear and rolled it forward - the cam belt is there enough to move and I couldn't hear any noise from the engine.

I'm also assuming the cam belt has slipped a bit?

So, the main question is, what to do now?

My biggest problem is that the car is at a relatives - about a 100 miles from home.

Presently, I'm thinking of scrapping it, but it’s only done 40,000 miles so it seems a waste. If I could get it towed back to my house I was thinking of trying to sort this out myself. I know it’s a lot of work, but I don't want to spend cash on paying someone to fix this, but think it could be a good way to learn, and, if it goes wrong all I’ve lost is the cost of the tow (which could be covered by the scrap cost anyway..)

The other kicker is that it was only serviced and MOT'd 4 weeks ago, and the cam belt was changed about 5000 miles ago. I only took ownership of the car a few months back but it’s been in the family since new before then.

Thoughts and opinions are greatly appreciated. Thanks.

 

[Recycled Scenic]

Hello and welcome to the forum

Sorry to hear the reason you've arrived here

The best thing to do is get the car home and check the engine timing first before removing the cylinder head.

The auxiliary belt and timing belt are both driven by the crank shaft so run side by side at that point so its not unusual when the auxiliary belt fails or starts to shred itself up for debris to get into the timing belt area to cause the timing belt to jump and the engine timing to get lost.

You might be very lucky but I doubt it ! that none of the valves have got bent? You say the timing belt I still in tact? So firstly I would check to see how far out the timing is. Remove the 2 blanking plugs from the end of the cylinder head and set the engine to TDC you will need a setting pin that’s 70mm long . With the crank at TDC the setting slots in the end of the cam shafts should be parallel. At this stage I wouldn’t worry to much about using a cam shaft locking tool,.just visually check Yours probably wont be parallel if they are only slightly out you might just get away with a new timing belt though a full kit is best.

The valve stems in theses engine are very weak so usually just get bent out of the way and allow the engine to carry on turning over.

I have just taken the cylinder head off a 1.4 K4J with a snapped timing belt the cylinder head gasket, cylinder head bolts, and full set of valves is going to cost me £89 + P&P from http://www.trechii.com/ and is exactly the same as for your 1.6 K4M they also do timing belt kits for just under £50 + P&P. I have used them several times as they are local to me and I can collect.

 

[rossb2]

Thanks for such a quick reply. In answer to your questions, firstly, no, I don't know if valves are bent, I'm only assuming no 'major' damage (i.e. engine not seized solid) as when I rolled the car forward in gear I couldn't hear any horrendous noises - I'm not sure if this is a valid assumption or not?

As for the state of the timing belt - The is about a 5mm rip right across the belt, its held together with only a couple of strands of rubber in the middle - but it was enough to hold it together to see it moving round when rolling the car forward in gear.

I'm going to go and 'visit' the car this weekend and do some investigatory work before deciding whether or not to get it brought back to my home.

Are there any other specific tools I'm going to be needing? I've pretty much only got a set of spanners right now... I guess a good socket set with a set Torx bits?

With regards to the engine - I thought it was a K7M 702, but you think it could be K4M?

 

[Recycled Scenic]

Sorry my mistake I have jumped the gun I missed read what you said. No your engine won't be a 1.6 K4M so wont be a 16 valve engine so disregard what I said about setting the engine.

As you said your engine will be the earlier 1.6 8 valve K7M sorry I don't know anything about those engines. But I'm sure some one else here on the forum will.

 

[rossb2]

Hi, no problem - thanks for your time, it's appreciated.

 

[Scenic 11]

Noticed that the cambelt was renewed 5000 miles ago surely it should be under warranty and also the alternator belt should have been changed at the same time as a matter of course so was it fitted by Renault or other if so have a word with them.

 

[marvintheandroid]

As a general principle, if the engine spins over on the starter faster than normal, this is a good indicator that there is no compression. This can then be confirmed with a compresion tester.

If you get zero compression on all 4 cylinders, valve damage is usually indicated.

Marv

 

[marvintheandroid]

The other kicker is that it was only serviced and MOT'd 4 weeks ago, and the cam belt was changed about 5000 miles ago. I only took ownership of the car a few months back but it’s been in the family since new before then.

Thoughts and opinions are greatly appreciated. Thanks.

Were the recent service and the cambelt change done by the same garage ? If so, definitely take the problem back to them. Of course it may not have been faulty parts or workmanship that caused the problem.

If they were done by different garages then your case against the guys who did the service is weak at best, unless you can show that they disturbed something or did a poor job.

Take a look at the receipt from the garage who did the cambelt - you didn't say how long ago it was - and see what sort of warranty they give. At least, you may be able to agree a parts only no labour arrangement with them.

Marv

 

[VelSatisfied]

A point worth mentioning, is that if the previous owner just chose to get the cambelt replaced, and the belt has failed due to consequential damage - then the warranty on the cambelt won't cover that aspect.

Also, how long (in time) has it been since the cambelt was changed? 5,000 miles is around half a year's motoring for most people, but for someone retired (for example) that could easily be 2-3 years ago.

HTH

Paul

 

[rossb2]

Sorry for a delay in response. All work has been done at different garages and the cam belt change was nearly 5 years ago, and more like 15000 miles not 5000 (even so, a low mileage over 5 years), apologies about the bad info. Anyway, I decided to get in there and I have removed the head - yesterday was an interesting day. It looks as if every valve hit, there are 2 marks on the top of each cylinder but they don’t look badly damaged. 4 valves are bent and now don’t sit properly. My aim is now to replace the valves. I have the Haynes manual (which i followed to get everything out). However, at this point any tips and advice are appreciated. I've got a basic understanding of the tool i need to remove valves and the concept of having to grind the new ones in. Is there any advice on the best place to get the new set from? Thanks again.