Worrying Engine Rattle - Help Please
Discussion
Hi everyone....I'm pretty sure the answer to this post is to take the Cerb to a TVR specialist but I wondered/hoped someone may be able to point me in a rough direction for an easy fix (wishful thinking maybe but worth a try)....
Firstly the cerb is a '99 4.2, about 30k on the clock and up to date on major service. The other month I started the car, drove out of the drive and changed into 2nd. As I started to accelerate (slowly, what with the engine still waking up) there was a bit of a clattering and then a rattling sound developed....sounding more like a loose / rattling exhaust than anything else, still I crawled back 1/2mile to home and parked her up.
In the cold light of day today I restarted her and it most definitely sounds like a rather worrying engine rattle, down low on the drivers side.....obviously I don't want to run the engine for fear of making matters worse but not running the engine makes the problem harder to diagnose....just wondered if anyone knew of some basic checks I can do / things to look for before the pound notes start to flow.
Thanks,
Mike
Firstly the cerb is a '99 4.2, about 30k on the clock and up to date on major service. The other month I started the car, drove out of the drive and changed into 2nd. As I started to accelerate (slowly, what with the engine still waking up) there was a bit of a clattering and then a rattling sound developed....sounding more like a loose / rattling exhaust than anything else, still I crawled back 1/2mile to home and parked her up.
In the cold light of day today I restarted her and it most definitely sounds like a rather worrying engine rattle, down low on the drivers side.....obviously I don't want to run the engine for fear of making matters worse but not running the engine makes the problem harder to diagnose....just wondered if anyone knew of some basic checks I can do / things to look for before the pound notes start to flow.
Thanks,
Mike
Edited by Mike_Cerb99 on Wednesday 7th July 21:11
I've been through all this "rattle diagnosis" business with my Cerb. It's just a case of eliminating things one at a time. It's unusual for a rattle to come from nowhere though, are you sure it hasn't been creeping up on you?
Obviously check all of the obvious sources first - exhausts, heat shields, etc. It's also worth pulling the vacuum pipe off the servo as I understand that when the valve on the servo starts to fail then it causes a ticking noise. Take each of the belts off, AC and alternator, I once had a noise that I traced to a bit of grit in a drive belt that made a noise every time it hit the pulley, that took some finding...
On my car I eventually traced the noise to failing gudgeon pins (!), it was a top endy type of noise, but load related - louder when no load. You can check this out by just pulling the spark plug leads one at a time and see if that stops it. If none of that sorts it, then you can check the valve clearances just to be sure. What's the oil pressure like? A big end noise is quite distinctive if you know what to listen for, however, you'd usually expect a bit of a drop in oil pressure if it's really gone.
If you still can't find it, then you've got to make your mind up as to whether to put up with it and see how it develops or pull the engine to look in greater depth. I ended up doing the latter - and am very relieved that I did. Keep us posted.
Obviously check all of the obvious sources first - exhausts, heat shields, etc. It's also worth pulling the vacuum pipe off the servo as I understand that when the valve on the servo starts to fail then it causes a ticking noise. Take each of the belts off, AC and alternator, I once had a noise that I traced to a bit of grit in a drive belt that made a noise every time it hit the pulley, that took some finding...
On my car I eventually traced the noise to failing gudgeon pins (!), it was a top endy type of noise, but load related - louder when no load. You can check this out by just pulling the spark plug leads one at a time and see if that stops it. If none of that sorts it, then you can check the valve clearances just to be sure. What's the oil pressure like? A big end noise is quite distinctive if you know what to listen for, however, you'd usually expect a bit of a drop in oil pressure if it's really gone.
If you still can't find it, then you've got to make your mind up as to whether to put up with it and see how it develops or pull the engine to look in greater depth. I ended up doing the latter - and am very relieved that I did. Keep us posted.
Not diagnosing per sa, but offering a little hope perhaps - as I had something similar, which, when we got her lifted, turned out to be the metal 'spacer' bracket on the exhaust underneath having come broken free - made a suprising noise when at particular revs, either on the way up, or more spectacularly on the way down under engine breaking...
A rather handy chap fashioned a new one which is considerably better quality, and the problem is fixed.
Thought I'd mention it by way of a possible cheap fix, and keep my fingers crossed for you.
A rather handy chap fashioned a new one which is considerably better quality, and the problem is fixed.
Thought I'd mention it by way of a possible cheap fix, and keep my fingers crossed for you.
With limited knowledge, I doubt I can add anything useful on this - however - does your car have aircon?
My Cerbera shook off it's aircon belt (and shredded it beyound recognition
). Horrible noises! When I investigated, it also appeared that the large 'wheel' at the bottom of the engine (more to the drivers side, sits just behind the chassis rail) had come loose - the nut was still on the end fortunately. Because this was loose it was causing all sorts of noises and rattles and clonks as it moved around 
.
Worth a quick look perhaps?
Good luck!
My Cerbera shook off it's aircon belt (and shredded it beyound recognition
). Horrible noises! When I investigated, it also appeared that the large 'wheel' at the bottom of the engine (more to the drivers side, sits just behind the chassis rail) had come loose - the nut was still on the end fortunately. Because this was loose it was causing all sorts of noises and rattles and clonks as it moved around .Worth a quick look perhaps?
Good luck!
I trick to help locating strange knocking noises especially on an engine/gearbox is to use a jack handle or pole. I believe a piece of wood may also work but not as well!
Basically using it like a stethoscope.
Cup your hand over the end of the pole and up to your ear now press the other end up to the engine (obviously with engine running and also taking care not to get caught in any moving parts or touch anything hot!!) You will hear the sound of the engine pass up the pole and if there is a knock or rattle you can detect its location more easily by touching different areas on the engine.
It's not %100 accurate but can help a great deal in tracking certain noises
Basically using it like a stethoscope.
Cup your hand over the end of the pole and up to your ear now press the other end up to the engine (obviously with engine running and also taking care not to get caught in any moving parts or touch anything hot!!) You will hear the sound of the engine pass up the pole and if there is a knock or rattle you can detect its location more easily by touching different areas on the engine.
It's not %100 accurate but can help a great deal in tracking certain noises
ridds said:
Where abouts in West Sussex are you? If you're not too far away I can pop over and have a listen at the weekend?
Hi everyone, thanks for all of the suggestions - will hopefully get her up in the air for an initial look one evening this week.....I'm just outside Chichester so APM is looking fairly local/good if the worst comes to the worst.Mike_Cerb99 said:
ridds said:
Where abouts in West Sussex are you? If you're not too far away I can pop over and have a listen at the weekend?
Hi everyone, thanks for all of the suggestions - will hopefully get her up in the air for an initial look one evening this week.....I'm just outside Chichester so APM is looking fairly local/good if the worst comes to the worst.Low down on the drivers side is the oil pump/power steering pump/water pump which are all driven off the same jack shaft.
Don't want to curse you, but possibly a broken shaft! It's more common on early cars.
Was just an offer, I work in engine development by trade, just trying to save people a few quid keeping cars on the road.
Any damage that was going to have been done has been done on the way back from where-ever it first made the noise. If it was a jackshaft failure, I'm pretty sure it would have either lost oil pressure or overheated on the way back.
Any damage that was going to have been done has been done on the way back from where-ever it first made the noise. If it was a jackshaft failure, I'm pretty sure it would have either lost oil pressure or overheated on the way back.
ridds said:
Was just an offer, I work in engine development by trade, just trying to save people a few quid keeping cars on the road.
Any damage that was going to have been done has been done on the way back from where-ever it first made the noise. If it was a jackshaft failure, I'm pretty sure it would have either lost oil pressure or overheated on the way back.
Sorry Matt, did not mean to shout you down!!Any damage that was going to have been done has been done on the way back from where-ever it first made the noise. If it was a jackshaft failure, I'm pretty sure it would have either lost oil pressure or overheated on the way back.
Just worried that if the woodruff key has failed, it could be slipping and making the noise.
Hi all,
Just a quick post to say thanks for all of the suggestions and I thought I'd give some feedback - decided to jack the cerb up and pull every engine cover off that I could, checking tightness of nuts/bolts/pulleys/belts etc as I went......I could only find a 'loose' bracket about half way up the engine on the passenger side but that was it - after ensuring it didn't clash with anything, I thought I'd be brave (or foolish) and turn her over again to check oil pressure etc.
Anyhow, she started perfectly and although rattling at first, less so than previous with 50psi oil pressure.....keeping my fingers crossed I let her run and after a short time, the rattling decreased and she ran sweetly.....as she'd sat for a while I can only think the rattle was due to oil completely draining down from the top of the engine hence making her rattle.
A cerb that fixes herself - must be a first!....thanks again for all of the help....MoT on Friday now - Gulp!
Just a quick post to say thanks for all of the suggestions and I thought I'd give some feedback - decided to jack the cerb up and pull every engine cover off that I could, checking tightness of nuts/bolts/pulleys/belts etc as I went......I could only find a 'loose' bracket about half way up the engine on the passenger side but that was it - after ensuring it didn't clash with anything, I thought I'd be brave (or foolish) and turn her over again to check oil pressure etc.
Anyhow, she started perfectly and although rattling at first, less so than previous with 50psi oil pressure.....keeping my fingers crossed I let her run and after a short time, the rattling decreased and she ran sweetly.....as she'd sat for a while I can only think the rattle was due to oil completely draining down from the top of the engine hence making her rattle.
A cerb that fixes herself - must be a first!....thanks again for all of the help....MoT on Friday now - Gulp!
Aahhh Haaaa!!! Just re-reading your first post. I had assumed you had driven the car when it was hot!!
All Cerbs rattle when cold, some more than others but they all rattle. It's the nature of the beast. Don't thrash it in this time let it warm up and it will be fine!! Mind you in this weather it shouldn't rattle too much If your worried now you wait till the winter its a very worrying sound but is normal.
Having said that... I can only assume your rattle is the 'usual' rattle of a cold Cerb!! (thats my disclaimer in case your engine goes pop you can't blame me!! lol)
All Cerbs rattle when cold, some more than others but they all rattle. It's the nature of the beast. Don't thrash it in this time let it warm up and it will be fine!! Mind you in this weather it shouldn't rattle too much If your worried now you wait till the winter its a very worrying sound but is normal.
Having said that... I can only assume your rattle is the 'usual' rattle of a cold Cerb!! (thats my disclaimer in case your engine goes pop you can't blame me!! lol)
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