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Old 8th December 2016, 18:25   #1
wildie1972
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Having had a few issues since buying my first ZT 1.8 turbo I'm beggining to wonder if I've made the right decision in buying one.

Ive replaced the turbo and inlet manifold gasket, found the power that was missing by retiming the cam shafts, sorted the cold spot in the heater matrix and replaced the turbo to tee piece cooling pipe all thanks to advice on this great forum.

The car has now developed an awful noise at 2500 revs at around 25 mph, it sound like a metallic rattle either from the engine or gearbox. I can also hear it at higher speeds when I'm driving it a bit harder and ease off to change gear. When i'm stationary the revs are a little erratic fluctuating between 800 and 1000 RPM and when I park it up and turn the engine off their is a popping noise coming from the exhaust it almost sounds like water going down a plug hole. All this has developed in the last couple of weeks.

I was an Alfa Rmoeo driver for a number of years and they can be problamatic but the ZT is pushing me to the end of my tether.

Last edited by Greeners; 30th January 2017 at 13:08..
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Old 8th December 2016, 18:28   #2
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Get yourself over to BigRuss for a T4 session & sound advice mate He's in Liversedge, I think? unless he's moved
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Old 8th December 2016, 18:53   #3
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Forgot to mention that when I'm sat in traffic the oil light flickers as well.
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Old 8th December 2016, 20:35   #4
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It sounds as though it could be a rattle from the big ends.

You say you have low oil pressure. This could be because of the revs going up and down at idle. Or worn big ends.

If you can rev the engine with the bonnet up and listen to the engine. Where does the noise, if any, seem to come from ??

This will give you an idea as to whether it's the engine or box.

One other thing that can give this sort of noise is a loose heat shield on the exhaust system.
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Old 8th December 2016, 22:12   #5
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Thanks for the replys Ill check the heat shields as I'm under it tomorrow to fit new rubbers to the exhaust. If the big ends are going wouldn't it make the noise all the time?
I'll lift the bonnet and give it a rev in the morning if the big ends are going I'm affraid the car is too as I've never done them before and dont fancy doing them on the drive.
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Old 9th December 2016, 09:48   #6
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Well the weather is pants so wont be doing much investigating today but I have checked my oil and water levels and found mayo starting to appear on the dipstick.

Surley the head gasket cant be going the previous owner had it done at the beggining of the year

Last edited by wildie1972; 9th December 2016 at 09:49.. Reason: spelling error
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Old 9th December 2016, 13:02   #7
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Quote:
Originally Posted by wildie1972 View Post
Surley the head gasket cant be going the previous owner had it done at the beggining of the year
It depends whether or not it was done properly!

Perhaps you've read about checking the liner heights, checking the head surface with a straight edge and careful selection of either the elastomer or MLS gaskets.

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Old 9th December 2016, 13:33   #8
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Hi.
It begs the question as to whether the oil was changed when the gasket was replaced? Also if the liners and ladder were supported when the head was off and the crankshaft was turned could make the main bearings rotate resulting in wear and loss of oil pressure? The fact you have had to reset the valve timing makes me think the job wasn't done by a reputable mechanic.

If the oil pressure is so low at tick over (3-5psi) so it puts the light on then to me there must be considerable wear or a weak oil pump.
Big end noise is a classic sound but not many these days will be able to diagnose it correctly, it takes more than just a rev.
Big ends that are worn make less noise when cold due to the fact the oil is more viscous and can take up a little more slack in the bearings, once hot the rattle usually get louder when you lift your foot slightly off the throttle, this is due to less loading on the big ends at this point, under acceleration or load and also with your foot off the accelerator the loading is higher (Engine accelerating = load, conversely engine braking = load)
Revving the engine then backing off with give you a quick burst of a rattle as will holding the the revs in neutral.
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Last edited by murphyv310; 9th December 2016 at 13:51.. Reason: Added sentence
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Old 9th December 2016, 15:23   #9
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So basically the engine may need a rebuild ? Head gasket head skimming and bottom end doing? Think it's going to be time to get rid and have the wife ferry me about.
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Old 9th December 2016, 16:06   #10
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Quote:
Originally Posted by suzublu View Post
Get yourself over to BigRuss for a T4 session & sound advice mate He's in Liversedge, I think? unless he's moved
Very sound advice.

An expert ear might find things are not as serious as you think.



Besides if your wife drives like mine then having her drive you about will be a fate worse than death.--

Quote:
Originally Posted by murphyv310 View Post
Hi.
It begs the question as to whether the oil was changed when the gasket was replaced? Also if the liners and ladder were supported when the head was off and the crankshaft was turned could make the main bearings rotate resulting in wear and loss of oil pressure? The fact you have had to reset the valve timing makes me think the job wasn't done by a reputable mechanic.

If the oil pressure is so low at tick over (3-5psi) so it puts the light on then to me there must be considerable wear or a weak oil pump.
Big end noise is a classic sound but not many these days will be able to diagnose it correctly, it takes more than just a rev.
Big ends that are worn make less noise when cold due to the fact the oil is more viscous and can take up a little more slack in the bearings, once hot the rattle usually get louder when you lift your foot slightly off the throttle, this is due to less loading on the big ends at this point, under acceleration or load and also with your foot off the accelerator the loading is higher (Engine accelerating = load, conversely engine braking = load)
Revving the engine then backing off with give you a quick burst of a rattle as will holding the the revs in neutral.
Hi Trevor.

I don't think the OP mentioned Head Gaskets.




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Last edited by Dragrad; 14th December 2016 at 01:39.. Reason: Consecutive posts, please use the edit or multi-quote options ;-)
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