Stilo
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Post by Stilo on Dec 22, 2012 20:25:15 GMT 1
Afternoon all. This one could turn out to be a Christmas horror story. A neighbour has a 2003 Laguna II 1.6 petrol. It shredded its alternator belt just as she was about to head off to her parents house 100 miles away, and then to fly on to the UK tonight with them to be with her sister for Christmas. We got her on her way by train and recovered her car back to her driveway. From what she said about what happened, there's a possibility that shredded belt might have become entangled around the crank pulley and derailed the timing belt. I've looked at it and the alternator belt is in so many pieces that I can't tell till daylight exactly what has happened or how bad it is though. One question I do have it slackening off the alternator belt tensioner. Obviously a spanner around the centre bolt will release the tension, but do these tensioners have a pin to lock them in the "slack" position, or can you pin them in place with something a drill bit? Or must they be held slack with good old brute force...? Thanks chaps and a very Happy Christmas to you all ;D
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french crap fanatic
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french car specialist based in dagenham east london
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Post by french crap fanatic on Dec 22, 2012 20:32:50 GMT 1
yes there is a hole which lines up and you put a pin/broken drill bit in to hold it. thats the least of the problems. the shredded belt bits do get into the crank pulley and make the timing belt jump. its a fully floating crank,altho most of the time the pulley is rusted onto crankshaft. reno dealers do a aux belt for around 30 quid here for 2 tentioners and new belt. good luck!!!
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Stilo
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Post by Stilo on Dec 22, 2012 20:45:00 GMT 1
Thanks for the heads up. I won't be going near this till the middle of next week. Even if the timing belt is ok, I'm wondering what caused it to shred. Obviously one of the guide pulleys, PAS pump or alternator itself might be goosed. Anyway, there's a fat man in a red suit that needs taking care of first....
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Stilo
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Post by Stilo on Dec 27, 2012 2:19:03 GMT 1
yes there is a hole which lines up and you put a pin/broken drill bit in to hold it. thats the least of the problems. the shredded belt bits do get into the crank pulley and make the timing belt jump. its a fully floating crank,altho most of the time the pulley is rusted onto crankshaft. reno dealers do a aux belt for around 30 quid here for 2 tentioners and new belt. good luck!!! Update on this and no, it isn't looking good. It took ages to extract all of the shredded aux belt bits that had entangled themselves in and around the PAS, alternator and tensioner pulleys. No debris was visible behind or around the crank pulley and the timing belt was still in place. Once the aux belt shreddies were removed, it was clear that the alternator initiated the failure because it was very rough to turn, and closer examination showed that the shaft bearing had failed which allowed the alternator's pulley to machine its way into the face of the alternator. There was swarf everywhere. We then tried to start it. It ran very rough, sounded like it lacked compression on cranking, and when it did fire, the whole thing sounded like a machine gun and was misfiring. Fault code P0314 (Single Cylinder Misfire -Cylinder not Specified) is also logged. I didn't progress any further but I'd wager that it did jump a tooth or two and has done some rockers and valves. In light of the cars age, it may not be worth fixing. Are there any other checks I can do that won't entail mass dismantling?
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Post by Monkey on Dec 27, 2012 22:35:40 GMT 1
Ah the good old K4M... The belts fall off left, right and anyway it wants!
Remove the air filter housing and pop the black camshaft plugs out. Fit timing pin in block and turn over with a ratchet/bar/spanner until it stops. Using timing tool, see if it fits or at the very least check camshaft cut outs are aligned.
That way you'll know if the timing has moved. Or just do a compression test or best of all, a cylinder leakdown test.
It will have bent some exhaust valves but good news is they very rarely damage bottom end. £3 valve a on ebay, head set, cambelt kit water pump and accessory belt kit and shes away!
Either that its a coincidence and a coilpack has given up. There crap too!
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Stilo
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Post by Stilo on Dec 28, 2012 13:16:54 GMT 1
Thanks for that - tis good advice . I don't have a timing pin but what I will do instead is to bring No1 up to TDC and see how the timing marks look on the rear of the cams. I reckon this will be the smoking gun alright
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Deleted
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Post by Deleted on Dec 28, 2012 20:56:41 GMT 1
Not sure if these time on tdc , sounds like its a
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Stilo
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Post by Stilo on Dec 29, 2012 19:56:36 GMT 1
Not sure if these time on tdc , sounds like its a I think you're right Mac. Got to look at this again today. There seems to be a slight difference between the slots in the cams alright. One looks slightly off-horizontal than the other but not massively. I can't tell exactly because I don't have the proper locking tools. Is it possible that these can break a rocker without doing a valve? If so, can the rocker be replaced with removing the cams. Or is valve bending absolutely guaranteed with these things? It's a shame because it's a clean car and the owner liked it a lot. If it needs major surgery, the owner said she won't go ahead with it because its uneconomic because of its age.
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Post by Rhubarb on Dec 29, 2012 21:07:35 GMT 1
Not sure if these time on tdc , sounds like its a I think you're right Mac. Got to look at this again today. There seems to be a slight difference between the slots in the cams alright. One looks slightly off-horizontal than the other but not massively. I can't tell exactly because I don't have the proper locking tools. Is it possible that these can break a rocker without doing a valve? If so, can the rocker be replaced with removing the cams. Or is valve bending absolutely guaranteed with these things? It's a shame because it's a clean car and the owner liked it a lot. If it needs major surgery, the owner said she won't go ahead with it because its uneconomic because of its age. As soon as you remove the rocker cover the cams pop out.. The caps are built into the rocker cover. If they cam lines don't match up perfectly then it's skipped a tooth.
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Post by Monkey on Dec 29, 2012 21:19:24 GMT 1
I worked for a Renault dealer for a while and 99% of the time when this happened we usually bolted a new head on as it equaled repairing the damaged head.
Every one i took apart had bent some valves, rocker assembly doesnt get damaged.
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french crap fanatic
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french car specialist based in dagenham east london
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Post by french crap fanatic on Dec 29, 2012 21:31:19 GMT 1
they time up on tdc. the flat sections of cams NEVER ever line up,as long as they are roughly equel its fine. cos the cams are held in with rocker cover what i do is put an airline down 1 or 4 or 2or3,if valves are good then engine spins over!!!! this way you assertin wether you have a broken rocker or bent valve. btw ive never had a broken rocker on these!!! are you sure plugs and coils are good? could be that simple!! esp if someone has been messing before you got the car. oh ive had injectors go open circuit on these cars before,not common tho!!!
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Stilo
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Post by Stilo on Dec 30, 2012 12:05:43 GMT 1
they time up on tdc. [glow=red,2,300] the flat sections of cams NEVER ever line up,as long as they are roughly equel its fine.[/glow] cos the cams are held in with rocker cover what i do is put an airline down 1 or 4 or 2or3,if valves are good then engine spins over!!!! this way you assertin wether you have a broken rocker or bent valve. btw ive never had a broken rocker on these!!! are you sure plugs and coils are good? could be that simple!! esp if someone has been messing before you got the car. oh ive had injectors go open circuit on these cars before,not common tho!!! I'm gonna look at this again. The cams line up roughly equal as you say. When I got it started, it half run all lumpy and sounded like a machine gun. I think it might be the battery which is all but dead now because the alternator was goosed. These have the credit card key, and I'm wondering if the machine gun noises weren't bent valves or rockers, but the starter solenoid not disengaging properly because the electronics are awry due to the battery being weak. Mad theory I know, but worth a second look at...
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french crap fanatic
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french car specialist based in dagenham east london
Posts: 3,355
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Post by french crap fanatic on Dec 30, 2012 14:47:24 GMT 1
def worth recharging battery or fitting a new one just to prove a point. reno cars use digital electronic to start and run the car and they dont like low voltages!!!
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Deleted
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Post by Deleted on Dec 30, 2012 16:45:56 GMT 1
Not sure if these time on tdc , sounds like its a I think you're right Mac. Got to look at this again today. There seems to be a slight difference between the slots in the cams alright. One looks slightly off-horizontal than the other but not massively. I can't tell exactly because I don't have the proper locking tools. Is it possible that these can break a rocker without doing a valve? If so, can the rocker be replaced with removing the cams. Or is valve bending absolutely guaranteed with these things? It's a shame because it's a clean car and the owner liked it a lot. If it needs major surgery, the owner said she won't go ahead with it because its uneconomic because of its age. Yes sorry TDC firing stroke end cyl next to cam slots ,top of the slots should line up with the lower edge of head flange face, if the belt is ok and cam sprockets set correctly on cams they should line up pretty much perfect when turning engine to setting position , have done a few of these and found the DIY bodge tippex marks on the cam sprockets and head and when set properlt with the tools they are often out of line slightly , in fact they are a git to do because of the crank sprocket and often when using a new bolt the sprocket moves,,or is it just me ;D
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Post by Karl on Dec 30, 2012 17:48:32 GMT 1
I think you're right Mac. Got to look at this again today. There seems to be a slight difference between the slots in the cams alright. One looks slightly off-horizontal than the other but not massively. I can't tell exactly because I don't have the proper locking tools. Is it possible that these can break a rocker without doing a valve? If so, can the rocker be replaced with removing the cams. Or is valve bending absolutely guaranteed with these things? It's a shame because it's a clean car and the owner liked it a lot. If it needs major surgery, the owner said she won't go ahead with it because its uneconomic because of its age. Yes sorry TDC firing stroke end cyl next to cam slots ,top of the slots should line up with the lower edge of head flange face, if the belt is ok and cam sprockets set correctly on cams they should line up pretty much perfect when turning engine to setting position , have done a few of these and found the DIY bodge tippex marks on the cam sprockets and head and when set properlt with the tools they are often out of line slightly , in fact they are a git to do because of the crank sprocket and often when using a new bolt the sprocket moves,,or is it just me ;D the crank sprocket and often when using a new bolt the sprocket moves,,or is it just me ;D[/quote] I don't know on this engine? Does it have a free floating crank pulley? On ford keyless pulleys always use a new bolt and always lubricate the back of the bolt head with a light film of motor oil, so preventing the bolt from " gripping " the pulley face too early while applying the torq angle
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