Cambelt fitting

[stu]

Anyone help
Just had a new cambelt fitted by my local garage,now i'm getting a noise like an alternator bearing or waterpump bearing going @ over 2000 revs
at tickover no prob's and the timings ok....

Any ideas......

[rip]

I have a car stethoscope in my toolkit (which has never been used), and do not live very far from some parts of Northants. If you want to meet up for a beer, PM me and maybe we can meet up and try to find the noise?

[Doug]

my Elan made a belt noise whir for about the first 1000miles after the change -- just an FYI. Still worth checking to be sure all else is okay and the belt is not too tight though.

[Monty]

When i put my cylinder head back together i got a whining noise from the cambelt and had to adjust the belt again, it`s quite difficult to get the right tension on the belt. BTW my noise was at idle

If it was me i`d go back to the garage

[John_W]

Stu,
If the car wasn't making the noise before the belt change, it sounds like the belt's too tight.
John

[Oliver]

I have just replaced my timing belt, water pump, idler and tensioner and am becoming a bit frustrated with regard to getting the tension correct. I`ve only done one timing belt before, on my MGF, which was easy because the tensioner has a built in tension gauge, so i got it right first time (beginners luck maybe).

Because i lack experience of changing many belts, i can`t satisfy myself that the tension is correct. It seems a bit loose (10mm) at TDC, correct (7-8mm), at about 60 ATDC, but with the cover still off, i`m getting a whine when i blip the throttle. As i said, the cover is still off and the belt system is silent at idle,
and it isn`t particularly loud when revved. Basically, i don`t know if the belt noise is acceptable. Presumably the belt and rotating parts will make some mechanical noise ?

I don`t want to re-assemble the car without being sure. Any advice / opinions received from person(s) with cambelt experience greatly appreciated !

Oliver

[Dico]

Oliver, I know Monty struggled/struggles like hell to get his tension right. It seems its a bit hit and miss. Perhaps run it for a week and recheck?

[Oliver]

Thanks Dico,

I`m not the only one then. I think i may be being over cautious. I`ll take your advice.

Oliver

[Sy V]

Post No 11111 in this area - beat that!

[Monty]

Thanks Dico,

I'm not the only one then. I think i may be being over cautious. I'll take your advice.

Oliver

Oliver,

Dico is correct, i found it very difficult to get the right tention right must of adjusted it 20 times
When i went to stoneleigh last year i left the belt cover off and asked Pinky Dave to have a check and he thought it was a bit slack. So went through it all again, i`m still not happy as i get a whining noise but can`t seem to get it right BTW I`m on a used belt but if you`ve got a new belt then it may find it`ll stretch slightly with time and the noise may go

Another thing i noticed when trying to get the timing belt on and timing marks lined up as soon as you start to adjust the tentioner the timing marks are out so you have to off set the timing to get them to line up

[RayD]

One of these might help to determine if the whine is tension related...

[Oliver]

Hi Monty , Ray, Dico,

I `ve now run the thing up three times till hot, and let it cool, each time checking the tension. I`ll do it again tonight ! Then i may get bored and put the thing back together and drive it before winter sets in !!!

Oh just one other thing, surely i have fitted the tensioner the right way up ?! The hex adjuster hole is below the mounting bolt. (In other words i am turning the adjuster anti clockwise to tighten) - see picture.

Thanks chaps

Oliver

[RayD]

Oliver,

It does say anti-clockwise to tighten... in the manual.

Just a few thoughts…

Reading the above… the whining seems to be related to new belts, particularly in Monty’s case. There’s no other reason springs to mind why a belt that’s had that much attention paid to it should be any noisier than all the other belts that have done 1000’s of miles.

You could assume it’s a bearing making the noise due to overloading, but the people with new belts have usually got new bearings.

It’s unlikely the toothed side of a belt that’s nearly right would cause it.

One good possibility is the plain side of the belt on the tension pulley – particularly if it sounds anything like a fan belt slipping.

If you can get it to whine at will, try spraying some water on the pulley and see if it stops, or changes tune.

Ray

[Monty]

Oh just one other thing, surely i have fitted the tensioner the right way up ?! The hex adjuster hole is below the mounting bolt. (In other words i am turning the adjuster anti clockwise to tighten) - see picture.

Thanks chaps

Oliver

mmmmmm just trying to remember but i`m sure the hole for the allen key was round about 10 oclock and i`m sure to add tention it was clockwise as i remeber when tighting up the tentioner it would tighten the belt further
maybe i`ve got mine on wrong

Wounder if someone else can confirm this? Mr Pinky?

[RayD]

It was this bit I read Jay...

[WayneP]

There were some conflicting posts on the direction to turn the tensioner. I convinced myself (at the second attempt) that the right way to do it is turn the tensioner clockwise against the spring tension, fit the belt and then turn the tensioner counter-clockwise to tension the belt (as stated in the manual). This means that the spring loading tensions the belt before the tensioner pulley bolt is tightened. The manual says: "For a used belt , the spring tension alone should be sufficient to meet the tension specification. For a new belt, a higher tension is called for, and it is necessary to to provide additional tension whilst the pulley clamp bolt is tightened."

My belt whines a bit also but I'm pretty sure it's not too tight. I've done a few hundred miles since fitting it now so I'll probably take the cover off, have a look at it and recheck the tension.

[dapinky]

I remember having this sort of quandry when i did mine - but i can't remember what the final result was

I know that it wasn't easy to get at the tensioner to put the spring in as my hands are bigger than those of an action man,and it took a while to get the tension correct, but i can't remember which way it turned to increase the tension ~ the first time it went in, it was the wrong way round, hence the problems with replacing the spring after it was fitted, but i can only assume that i would have persevered to do it as per the manual, otherwise it would have been left as it was

I just sort of 'guessed' the tension as i didn't have access to a proper gauge, or a 10Kg weight, but it didnt snap or screech, so must have been okay. ('Guess' is probably not really a good expression - it was a considered process with firm finger pressure and a ruler, and i've done a few on other cars over the years, but never before on an elan!)

As Monty says, i did have a gander at his at Stoneleigh, and it looked a bit slacker than mine was, but i don't believe it has caused him any problems.

I think that if you have new bearings and water pump, then a belt which is too tight will be okay in the short term as the other components will be good for the extra strain on them, but with older rollers and pump, they could easily fail. A new belt will stretch in the first thousand or so miles to give a 'working length', hence the different tension flexing on a new belt to a re-used one.

All in all, it is worth checking (or having checked) the tension with a proper gauge to avoid the posibility of belt, bearing, tensioner, pump or cam bearing failure in the future.

Sorry i can't really remember how i did it (probably a fair bit of luck and good fortune):roll:


P.S.

Ray - good tip about using the wallpaper joint roller to see how the noise changes with tension whilst the whole lot is in motion - i've often thought about how such a thing could be achieved, and all the time the answer is in the garage cupboard!!!

[RayD]

Thanks Dave,

An easy way to remember which way it turns…

All tensioners tighten in the direction of the belt travel – it’s so they can be automatic, power assisted, failsafe, and so on.

So in this case it definitely turns anti clockwise to tighten.

Ray

[dans]

I had/have problems with a "whine" that I've never cured, see here

After changing the cambelt and all associated components it was never cured.

I think it may be CAS related a suggested at the bottom of the link above, but have never got around to investigating all the way.

Dan

[Oliver]

There are some interesting ideas here - the point about the tensioner applying pressure in the direction of travel is a good one, that makes sense to me. I`m putting it back together Friday eve, i want to have a (gentle) cruise down to Dungeness on Saturday afternoon, i don`t want to miss the sunshine. Is the `90 degree twist` check applicable on the top belt run between the cam pulleys ? I`m still getting 10mm movement at TDC, 7mm at 60 ATDC. I`m not sure why the difference ? Surely the belt can`t be unevenly stretched already ? Or is there some science here i don`t understand ??

Thanks to you all.

Oliver