At idle the engine is totally normal, when revving it (hard or gentle) in neutral, it is totally normal.
But start to drive and put a bit of load on it and I get a ticking noise which seems related to engine speed.
It sounds like the noise you get on some older less well-maintained cars, but I don't think it's as loud.
My initial thought was a hole in the exhaust manifold, but I don't know whether it would make that type of noise.
It certainly sounds like it's some sort of escape of a small amount of gas or something similar. Could it be a loose spark plug??
The car is an Alfa 145 with a 1.6 Boxer engine.
Cheers
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If its worse when the engine is cold, it could be what is known as Piston slap. Where the pistons and bores have wear and the piston is slapping when moving up and down the cylinder, or it could be noisey injectors if any are fitted and it could be a small leak in the exhaust somewhere near the front of the system.
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Hello
Hydralic tappets.
--
(iam not a mechanic)
Martin Winters
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Cheers for the replies.
May I add that the noise only started after I had my clutch replaced (see previous thread www.honestjohn.co.uk/forum/post/index.htm?f=2&t=26...3 ), which makes me think it's something to do with the manifold connections.
What could they have done to it, to make it tick?
I don't want to take the car back to that garage, I've had enough bother with them already.
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It sounds as though it is not the engine but the Clutch/gear box. At 3000rpm your injectors are purring as are your tappets so I doubt it is that you can here. Even one duff injector would be humming at 25 hz i.e. 25 times per second mind you the clutch is revolving at 100 times /second. I would inspect all the drive belts very carefull incase one of them is nicked/ relaminated or what ever so it makes a noise as it rides over a pulley. Try and establish how fast the tick is. If you can record it on a dictaphone then slow it down. If that still does not allow you to count it, trnsfer the slowed recording to another recorder and repeat process then work back and find the repition rate, it might point to your problem. Regards Peter
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bob
The noise you describe certainly matches the symptons for a tiny exhaust manifold gasket leak, or perhaps a manifold to exhaust joint. How easy is it to nip up the maniold nuts on the Alfa?
JS
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I don't know John, but I need to get it on some ramps or over a pit and take a look.
One of my friends mentioned some 'studs' that could have been broken when the garage did the clutch. What are they??
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I suspect from the noise you have either a broken manifold gasket or a cracked manifold - which opens up with heat and speed.
Best test is to have the car over a pit ( or ramps but pit is far better), go underneath and with a hand carefully go round all the joints whilst the engine is being revved - beware of burning yourself. If you hear a ticking you will feel gases escape. Alternatively you could let it ll cool down, cover the joints in water, start up and look for bubbles before the watre evaporates.
It is likely the garage who worked on your car let it hang by the exhasut and strained the various joints.. if you can find where it has gone, go back to them and ask them to fix it. But on second thoughts they sound incompetent and could make it a LOT worse...
madf
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I'll take it to a pit that I have access to and have a good look at it.
If it's a cracked manifold, I'll be taking it further. If it's a loose clip, or loose manifold itself, I'll fix it myself.
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