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Discussion Starter #1
Last weekend we had a bit of a disaster, both Lagunas down within 12 hours! Alternator on one (now sorted), the other (2.0L 8V, '97 estate) auxilliary drive belt bottom pulley (from crankshaft) fell apart. Have replaced the pulley (no other obvious damage) but now it wont start. The motor spins, has compression in right hand cyl, a spark there too, and the camshaft spins (visible through oil filler).
Is there some kind of sensor which may have been affected by the belt not running, and if so how could it be reset?:confused:
I'm now stuck!!!
Won.
 

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Hi there, it could be possible that the cam belt was damaged when the pulley fell apart Or the tdc is not set up properly, hopefully none of the valves has been damaged but I would wait until one of the tech guys gives you more advice.
Regards Leroy
 

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Discussion Starter #3
Thanks for the quick reply Leroy,
The cambelt looks ok to me, there did not appear to be any damage inside the plastic enclosure.
Where is the TDC sensor and how does it work? I understand what it is (top dead centre location) but how would it be affected?
 

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Sounds to me as though the cambelt could indeed have jumped a few teeth....

I'd take the plastic cover off and have a good look at the timing marks.

I can't think of any other reason for the car not starting......:eek:

Just to doubly make sure,the remote central locking still works,I guess?.
 

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I don't think there is a sensor as such on the 8 Valve lag, there are timing marks on the front of cam shaft sprocket which should line up with a little mark or be lined up vertically
at the highest point, there should be a O degree mark on the transmission bellhousing which should be lined up with the mark on the flywheel. If I remember correctly you have to rotate the crankshaft by hand using a spanner or socket until the marks at both ends of the engine are in line, I'm sorry I can't be more helpful but I'ts a bit tricky without a manual or pics
Regards Leroy
PS If after turning the crankshaft and checking the timing marks and you can't get them to line up properly, then you will need a locking tool and the Haynes Manual, Good Luck
 

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Discussion Starter #6
Thanks Guys,
I've just come back in from the pouring rain and I really dont want to have to strip too much out in this weather.
According to Haynes there is a crank locking position using a dowel, but I have taken off the cambelt top cover and the belt is in excellent condition (Only changed last summer).
Any more thoughts?
Won.
 

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Laguna Cambelt

Yeh the weather is foul at present - know how you feel. Whilst the belt may appear in good condition it doesn't mean it hasn't jumped a few teeth. Your next step is to check the timing marks - you dont need a dowel to do this. Have you rotated the belt and checked if any teeth are missing - also is it tensioned correctly. Just hope you haven't bent any valves as the cost of repair could be greater than the value of the car. You have all my sympathies and good luck:)
 

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Discussion Starter #8
Update

Well sorry for the late update, but i've been away with work commitments. It does indeed appear to be the cambelt slipping, quite a few teeth too by the looks of things.
I took off the cylinder head cover and not all the valves have come back up with the cam lobes, is this normal or should they all follow the lobes to the top of their stroke?
I have been told that it is bent valves and it would cost £700 to fix. As that is near to the cars value I will have to have a go myself. The way I see it is that I have little to lose. I am not a complete beginner to home mechanics but I am a bit apprehensive about this one, it is quite an involved job......
The worst part of all this is I cannot get around as much as the wife needs the other car for work.
Anyway, we shall see how it goes.
Won.
 

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If there is a large gap between the cam follower/valve bucket and the bottom of the cam lobe,then the valves bent.:(

The 8 valve engines are straight foward to work on,so I'm sure you'll be OK.New valves are around the £10-£20 mark,depending on where you get them from, a gasket set should be around £60-£80,a set of new head bolts around the £30 mark and a new cambelt should be around £20.Remember to lap the new valves in,get the head face lightly skimmed to make sure it's straight and true(usually around £20 from a specialist engineering company,but worth the extra expense),and the job should be easy enough.

If you can find a decent second hand head with the valves already in it,then thats even better!.All it is then is a case of swapping them over.

Good luck and let us know how you get on.

Edit;Just one thing,the new valves will need the valve clearance gaps re-shimming.If your in any doubt about how to do this,then get back to us,or get an engineering company to do it for you at the same time you have the head skimmed.:)
 

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Discussion Starter #10
update

Well, I did it. Got her running tonight after charging the battery.:d
Managed to get a secondhand head from a scrapper for 50 quid, condition very good, just needed a good clean. Gaskets, belts, head bolts and a few other bits for £150.
The inlet valves were all bent and the piston crowns were marked slightly but nothing serious there.
I took my time and made sure I did a good job, at least the sun was shining!
Only problem to appear is the thing runs a bit too fast, so any thoughts would be appreciated on that.
Now for an MoT test and Tax, nearly there.
Thanks for all the help guys, I'll try and get a pic of the bent valves to post for interest.
Won.:cool:
 

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Well done Wonsterwon!:)

Not sure about the fast running,apart from check the amount of slack on the throttle cable.

I would be interesting to see some pics of the valves.:):)
 

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Just a suggestion some of the 8 valve engines have a throttle control valve which can get kinda grimey - try a clean or replace it.:)
 

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Discussion Starter #13
Sorted the fast running thing now; somehow I had managed to lose the rubber bung from a pipe on the side of the inlet manifold (next to the pipe that goes to the fuel pressure regulator on the fuel rail). This was allowing too much air in and causing the fast running (Checked against the other car).
Now I just have to wait a week for my MoT, I suppose it gives me plenty of time to check everything else out.:)
 
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