Additional advice on cambelt slippage

[Tkul88]

Had my cambelt slip a couple weeks back. Been researching everything since then.

Spoke to dan@sjm who was very helpful and mentioned most of the time the valves bend and a new head/engine required. Signs that the aux had frayed, catching in the crank pulley, resulting in the slip.

To cut a long story short, had a colleague come to look at the car. He's adamant the timing is out, but not enough to cause contact with the valves. We started it up and it does indeed run on 4 cylinders (previously thought 3) and rev cleanly. It was down on power when I pulled over after the breakdown though.


It doesn't sound that bad. Sounds similar to when the dephaser is knackered (as far as I can tell from a million YouTube videos).

My plan has been to start fault finding from cheapest to most expensive. My next job is getting tools and reseting the cambelt and possibly changing the dephaser, then if not, I'll remove head and potentially get a new head/engine fitted depending on the damage.

This is how the cams are sitting at TDC.

If someone can tell me that angle will definitely knacker the valves, then I'll skip straight to removing the head. Estimated at between 10-20 degrees out.

If not, I'm going to re-time with a new belt and crank it over (pending advice on below), if not I'll fit a new dephaser and see if it's any better. Probably compression test from here and move on to finally replacing head/engine.

My other question is, is it possible to 'break' the dephaser from the cambelt slippage?

Can I also run the car if timed correctly with a broken dephaser?

Cambelt kit, dephaser and aux were all changed last year.

I'm happy to crack on and do this because I've got nothing to lose at the moment and know the risks.

Also learnt a crap-load from this, feel so much more confident jumping in and troubleshooting myself now.

Sorry about the massive wall of text!

Thanks

 

[bloke]

bit of a rubbish photo but this was at tdc, took out all eight exhaust valves.

 

[Tkul88]

Has that gone backwards? Or almost gone round 360 degrees?

 

[Tkul88]

Actually ignore that, it's the belt assembly that slips right, not the cams.

Does that mean your crank would have gone round a fair bit further before the belt stopped slipping for it to be out 'backwards'? Hence the damage to all 8 valves?

 

[bloke]

came in as a job, was running rough, then cutting out and eventually wouldn't start and had no compression by the time it came in to me. slipped due to crank bolt not being tight, cams were tight, doubt they had even been touched. think the tensioner was out as well but can't remember. white paint marks everywhere gave a bit of a clue that it wasn't done properly.

 

[dajones]

Think the best bet is to get the head off and check if all the valves are sitting flush. I did that as a precaution when my belt slipped on the 1.2, found 6 bent valves.

 

[Tkul88]

Yeah I think this is the best bet. I'm borrowing a endoscope to check out the pistons. Least that will tell me how bad the damage is if the valves are knackered.

 

[bloke]

you need to get a vac test done on the head, stems can also double bend so the valve will shut fully but not actually seal.

 

[incy-spider]

If you say it's because the aux belt has wound into the cam belt and caused it to jump the timing then strip the timing belt off, remove all signs of debris, get a new gates kit and reset the timing like you say, you may be very lucky!! You only need to assemble it as far as getting the crank pulley back on to test the engine, don't go pulling the head of before you have tried it. Fingers crossed for you

 

[Tkul88]

Yeah belt first then I'll look at the valves.

Thanks! My mission this weekend.

Seem legit? http://www.ebay.co.uk/itm/RENAULT-CLIO-2-0-172-SPORT-CB1N-TIMING-BELT-KIT-GATES-/220406251927

 

[bloke]

bit dear