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Oh no ... knocking....HELP ME


ManwithSupra

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Got a strange loud knocking sound coming from the front of the engine, it is speed related and it seems to be coming from the top of the engine where the cam sprockets are, i have taken the cover off and listened while i revved the engine which the noise starts to dissapear when the revs get higher, when i come off the throttle the noise reappeared as normal

 

I have not had any dip in power as far as i can tell and the sound seems to sound like a plastic cover being nocked but when i checked i could not see any problems or anything in the way of the cambelt, which leads me to belive its something on the inside of the engine however when i plac my ear over the oil filling hole you cant hear any sound resonating from there, however you can feel the knocking on the top of the engine and you can hear it in the car, also when the car in Drive (its an auto) and stationary the noise is even louder ??? So i really dont know what to think can anyone help

 

Video added - Sorry not a very good quality one - will post a better one soon.

 

http://www.youtube.com/watch?v=eHrRLo3B2nw

 

This is while it is idling (as this is the only time the sound is present) and close up to the cam sprocket which is where the sound seems to be coming from- please note there is no missfire either and the sound is "plasticy" i.e it does not sound like a metal sound.

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dosent sound good,check for obvious, belts/pulleys running aligned etc, crank pulley also, cam belt as youve mentioned,maybe the cam belt tensioner? although you said it sounds like its coming from the top its worth stripping the covers off to check else you could be looking at more dosh,maybe a vid clip or something may help but i wouldnt drive it till youve had a good chance to look.

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I had simiolar problems? Turned out to be cam belt tensioner / bearing inside.

It does sound like the same problem. Take the belt off and run for a few seconds. If the sound goes away, bingo!!!!

 

You mean the accessory belt I hope - engine isn't going to run too well with the cambelt off!

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Do you mean the cambelt tensioner or the aux belt tensioner

 

He meant aux belt tensioner...

 

The 'harmonic balancer' *or 'crank pulley' as some prefer* is at the bottom of the engine as you look at it from the front...

The aux belt runs around it... a good visual inspection should tell you if its in trouble or not.

 

If that looks in good order, then as above, you could remove the aux belt and start the engine and see if the noise has gone (dont run it for too long or you will flatten the battery)

 

If the noise is still there and seems to be coming from the timing belt cover...

 

You may need to replace the cambelt auto tensioner assembly.

the cam belt tensioner is hydraulic and cannot be tightened further but iirc the idler gear could be the culprit.

 

Either way, new cambelt and tensioner assembly and also new drivebelt and drivebelt tensioner...not a cheap set of parts but well worth doing both at the same time because 'if' one has failed, the other may not be far behind

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He meant aux belt tensioner...

 

The 'harmonic balancer' *or 'crank pulley' as some prefer* is at the bottom of the engine as you look at it from the front...

The aux belt runs around it... a good visual inspection should tell you if its in trouble or not.

 

If that looks in good order, then as above, you could remove the aux belt and start the engine and see if the noise has gone (dont run it for too long or you will flatten the battery)

 

If the noise is still there and seems to be coming from the timing belt cover...

 

You may need to replace the cambelt auto tensioner assembly.

the cam belt tensioner is hydraulic and cannot be tightened further but iirc the idler gear could be the culprit.

 

Either way, new cambelt and tensioner assembly and also new drivebelt and drivebelt tensioner...not a cheap set of parts but well worth doing both at the same time because 'if' one has failed, the other may not be far behind

 

Thanks for this, its typical something like this happens just as i was going to order a nice set of ikeya supension arms for me supe....looks like that will need to go on hold for now...:(

 

From what you have heard from the video clip does it sound more like the tensioner then a internal issue like big ends :(

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Thanks for this, its typical something like this happens just as i was going to order a nice set of ikeya supension arms for me supe....looks like that will need to go on hold for now...:(

 

From what you have heard from the video clip does it sound more like the tensioner then a internal issue like big ends :(

 

To be honest Im struggling to make much out at all from that video :search:

 

Can you outline the history of the noise?

eg/ when did it start

how did it start (eg/ where you revving/driving hard etc)

 

Does the noise rise in line with revs?

eg/ the noise starts at idle and by 3krpm it has gone, for example

 

Have you got a local forum member who knows their Supes?

maybe a friendly forum member could pop over and take a look for you?

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To be honest Im struggling to make much out at all from that video :search:

 

Can you outline the history of the noise?

eg/ when did it start

how did it start (eg/ where you revving/driving hard etc)

 

Does the noise rise in line with revs?

eg/ the noise starts at idle and by 3krpm it has gone, for example

 

Have you got a local forum member who knows their Supes?

maybe a friendly forum member could pop over and take a look for you?

 

 

This noise only started recently, however up to this point i have been getting a knocking noise while the car has been in Drive and stationary for a few months i posted this issue a while back where the general comments were that the exhuast was more than likley knocking on the tranmission tunnel or gearbox as there is a common thing apparantly so put it down to that - again no loss in performance or random noises or blips/misfires from the engine.

 

Over the last couple of days i have not really been driving it hard at all. I only noticed the noise when i was at traffic lights and ended up switching the stereo off .. then i heard a knocking noise when the car was in N, i then put it in Drive while stationary and it got alot louder, so not sure if these two noises are linked or just this new one is making the other one seem louder.

 

The noise is engine speed realated but only happens at idle, when you rev to 1k it gets faster about (im guessing as i did not see the rev counter) 2.5 -3k it goes away compleatly, then when you let off it comes back at idle.

 

Your right the video is not great but to be honest the sound is exactly the same, but whats being filmed is the intake cam sprocket (as this seems to be where the noise is coming from or that area anyway) i will see if i can do another video tonight or during the day in friday.

 

I have done lots of searches on the forum for noises etc, some of which i have found that some knocking is due to the Torque converter on the way out, however this is accompanied by slipping of the autobox and odd behaviour and i cant see why if it is the TC why it sounds like it coming from the front of the engine so have dismissed that as an issue.

 

I will try to do the Aux belt check (taking it off etc) and seeing if the noise is still there, if it is then i will take all the covers off the timing belt area and see if i can look at this Cambelt tensioner and see if the noise is coming from that if it is i will get the parts and replace all the tensioners and all belts etc.

 

If i still get the noise and cant locate it i will book it into a garage and see what they can do.

 

Anyone reccomend Toyoda Tech in Southampton at all??

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This noise only started recently, however up to this point i have been getting a knocking noise while the car has been in Drive and stationary for a few months i posted this issue a while back where the general comments were that the exhuast was more than likley knocking on the tranmission tunnel or gearbox as there is a common thing apparantly so put it down to that - again no loss in performance or random noises or blips/misfires from the engine.

 

Over the last couple of days i have not really been driving it hard at all. I only noticed the noise when i was at traffic lights and ended up switching the stereo off .. then i heard a knocking noise when the car was in N, i then put it in Drive while stationary and it got alot louder, so not sure if these two noises are linked or just this new one is making the other one seem louder.

 

The noise is engine speed realated but only happens at idle, when you rev to 1k it gets faster about (im guessing as i did not see the rev counter) 2.5 -3k it goes away compleatly, then when you let off it comes back at idle.

 

Your right the video is not great but to be honest the sound is exactly the same, but whats being filmed is the intake cam sprocket (as this seems to be where the noise is coming from or that area anyway) i will see if i can do another video tonight or during the day in friday.

 

I have done lots of searches on the forum for noises etc, some of which i have found that some knocking is due to the Torque converter on the way out, however this is accompanied by slipping of the autobox and odd behaviour and i cant see why if it is the TC why it sounds like it coming from the front of the engine so have dismissed that as an issue.

 

I will try to do the Aux belt check (taking it off etc) and seeing if the noise is still there, if it is then i will take all the covers off the timing belt area and see if i can look at this Cambelt tensioner and see if the noise is coming from that if it is i will get the parts and replace all the tensioners and all belts etc.

 

If i still get the noise and cant locate it i will book it into a garage and see what they can do.

 

Anyone reccomend Toyoda Tech in Southampton at all??

 

lol at small bongo player :D

 

Im not aware of Toyota tech but I have met the guys at Toyota GT in Hampshire and can heartily recommend them..

 

Youve had the noise for a few months??

 

I think doing the tests suggested in the first instance is a good idea.

 

Then post back your findings...or alternatively take it to Toyota GT asap!

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I had this with a car where the harmonic damper was loose. It had chewed up the key way in the crank and worn the crank nose, because the owner left it hoping the noise would fix itself :) I'd have a good look in that area, and check the torque on the crank pulley bolt. If it's loose re torquing is NOT a satisfactory fix!

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I had this with a car where the harmonic damper was loose. It had chewed up the key way in the crank and worn the crank nose, because the owner left it hoping the noise would fix itself :) I'd have a good look in that area, and check the torque on the crank pulley bolt. If it's loose re torquing is NOT a satisfactory fix!

 

Ouch!

Did he go with a new/used engine Chris or did you rebuild his current one with a new crank and a bottom end rebuild?

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Guest DaveWilko

My Celica Carlos Sainz had a similar though not as loud knocking which was also only at certain rpms and turned out to be a loose crank pulley. I was lucky, it had just chewed halfway through the woodruff key. The theory was that the imbecile who replaced the cambelt had the wheel off and didn't clean the crank nose before refitting the pulley wheel.

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I had this with a car where the harmonic damper was loose. It had chewed up the key way in the crank and worn the crank nose, because the owner left it hoping the noise would fix itself :) I'd have a good look in that area, and check the torque on the crank pulley bolt. If it's loose re torquing is NOT a satisfactory fix!

 

if this the case is a new crank pully in order or would there be more parts to check?

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if this the case is a new crank pully in order or would there be more parts to check?

 

It depends on the reasons that it came loose (if indeed it is lose!!), and also what damage has been done by driving around on it - have you been able to check yet? it should be pretty obvious, if you grab hold of the damper and see if there is any play, and also watch it when the engine runs and see if it wobbles..

 

in all likelihood if it is the harmonic damper/balancer, and the woodruff keyway is shot, it could point to a thrust bearing issue iirc that due to excessive vibrations has caused it to come loose..amongst other possibilities of course.

 

but, no,if its that, this far down the line, a new pulley wont fix it IMO. It will be new crank and engine rebuild time.

Or a new engine :blink: Im afraid to say.

 

But still, you havent checked it yet by the sound of it?? so nothing is certain until the problem is identified

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