BenM 0 Posted August 31, 2006 Hi all I have a 1990 1.8 16v that has a slight rattling coming from the front end of the engine. It is present at idle and is worst at around 1500rpm but then the resonance dies off as the revs increase. My immediate thought was that it's probably just something loose and rattling inside the timing belt cover and so far I haven't worried about it too much. But I've got a 400-mile round trip at the weekend and a mate suggested it might be the belt tensioner, which if it gave up could cause belt slip and a knackered engine. Does this sound likely? Are the tensioners on these engines prone to sudden failure? Engine is 107k old and to my knowledge the tensioner had never been replaced. Should I be worried? Cheers Ben Quote Share this post Link to post Share on other sites
bluester 0 Posted August 31, 2006 mine does the same replaced the water pump it cured it a bit but noticed there is a pulley (i think its a guide pulley) with a brass bearing that rattles about, maybe check that Quote Share this post Link to post Share on other sites
BenM 0 Posted August 31, 2006 I've had that problem - replaced the water pump pulley about a year ago. I'm pretty sure its just something loose but need some reassurance that its not gonna blow up on the motorway..... Quote Share this post Link to post Share on other sites
Supercharged 2 Posted August 31, 2006 just something loose and rattling inside the timing belt cover and so far I haven't worried about it too much You don't want anything loose in there mate - thats what the cover is there for! 16V's should have a belt change at 60k intervals and the tensioner should always be replaced at the same time, if it's not been done get it looked at straight away but i'd get the cover off first to check the bearing isn't breaking up - if it is you will see swarf all over the place and you will probably see its off centre - don't even start the engine! If it's not the above then yes probably the water pump. Quote Share this post Link to post Share on other sites
BenM 0 Posted September 1, 2006 Now I'm worried. I'll get it checked out.... Quote Share this post Link to post Share on other sites
davidwort 0 Posted September 1, 2006 I've had that problem - replaced the water pump pulley about a year ago. I'm pretty sure its just something loose but need some reassurance that its not gonna blow up on the motorway..... It could well be that again, they're a pile of poo and start to rattle as soon as the new one's on. Alternators and PS pumps can also make a fair bit of noise as they get old and worn, not to mention the water pump. Get a long screwdriver, preferably with a hard handle, press it against various parts of the engine and ancillairies with the engine running (mind the belts!), and listen to the top of the handle, you should be able to hear bearings, rattly pulleys etc quite clearly rather than the muddled mix of noise when you just lift the bonnet. David. Quote Share this post Link to post Share on other sites
BenM 0 Posted September 1, 2006 Right. I've had the front cover off and the back of the cam belt is very shiny and has crazed cracks all over it. There is also a pronounced rib down the middle of it like its been rubbing on something. I started the engine with the cover off and it looks like the rattling noise is the belt hitting the cover - the belt vibration changes with the revs and its resonating at 1500rpm and rattling off the cover. 2 questions: - I assume the back of the belt shouldn't be all shiney with surface cracks? This looks like a very bad thing. The belt is around 22k old. - Where is the tensioner? I couldn't see it when I had the cover off. Think I've had a lucky escape - hired a car for my weekend trip, car booked in for Wednesday to get looked at. Cheers Ben Quote Share this post Link to post Share on other sites
colinstubbs 0 Posted September 1, 2006 - Where is the tensioner? I couldn't see it when I had the cover off. :shock: Wooah, Scary!!! Lucky escape all right. Quote Share this post Link to post Share on other sites
FTM1975 0 Posted September 2, 2006 i had a similar problem, thought it was the belt tensioner, turned out to be the water pump. Replaced it and problem solved! Quote Share this post Link to post Share on other sites
Supercharged 2 Posted September 5, 2006 I didn't want to worry you but I'm glad I did now!!! Quote Share this post Link to post Share on other sites
BenM 0 Posted September 5, 2006 Yeah, cheers for the advice - could have been a very expensive weekend! Quote Share this post Link to post Share on other sites
BenM 0 Posted September 7, 2006 Just picked the car up - the tensioner pulley had seized solid, so the belt was just rubbing over the tensioner and getting slowly eaten. There was about a rizla width of rubber left on the belt! I think the car knew its about to be sold - I'm finally in a position to buy a VR6! Those chains may have problems of their own but at least they're unlikely to snap! Quote Share this post Link to post Share on other sites