Belts too tight ?

[ktel]

I had recently my belts done and now I think my engine whines a bit...

I 've posted a video with my engine sound. Is this whine normal?

Should I recheck tention ?

Thank you!

Video

 

[Waylander]

sounds about right, but im no expert, my 68 sounds about the same

 

[RS2000CUSTOM]

I would not worry about a slight whine on start up

Mine whines and then goes quiet with only the slightest whine after a minute or 2

When I carried a lot of repairs including the belt changes I was initially worried and kept going back to the belt tension etc

At one stage I removed the guide wheel and the whine almost disappeared - the guide is the one that is not in constant contact with the belt and its as though it has to get up to speed to then go quiet

Hope this helps

 

[amrbose14]

I had a similar experience. After some further troubles which were only related in who had worked on the car, the belts were replaced again by Promax. After that the whining went away. Doesn't really help you, except that it seemed to indicate that it didn't have to whine.

So maybe there is a proper way to do it?

ORIGINAL: ktel

I had recently my belts done and now I think my engine whines a bit...

I 've posted a video with my engine sound. Is this whine normal?

Should I recheck tention ?

Thank you!

Video

 

[pauljmcnulty]

Should I recheck tention ?

Need to check it after 1000 miles, so worth asking then.

 

[George Elliott]

I agree the video sounds a bit belt whiney, there is a tendency to over tighten them. The correct tension is difficult to describe and can only really be guaged by feel, it is surprisingly loose to touch.

The issues with an over-tight belt are the tension is applied to the rollers / water pump, cam shaft / balance shaft bearings, and causes wear, and it also sounds like a Zanussi on wash cycle.

Good reasons to get it right in my book

George
944t

 

[pauljmcnulty]

The correct tension is difficult to describe and can only really be guaged by feel

Or, there are two Porsche belt tensioners free to borrow for Club members... []

 

[Steviebear]

How do we get access to these please Paul?

 

[George Elliott]

Or, there are two Porsche belt tensioners free to borrow for Club members...

Paul, you'd be surprised how many different tensions they can produce depending on operator.......

I know I know, if used correctly []

George
944t

 

[pauljmcnulty]

ORIGINAL: Steviebear

How do we get access to these please Paul?

Call Club office. Paul Grainger normally deals with them, but anyone should be able to help.

You need to stick a deposit on a card, and I'd recommend registered post, but it's a great benefit.

I'd appreciate any ideas for tools we could buy in and use. Electronics seem to be deemed too fragile, but expensive specialist tools we can club together to buy, and then borrow?

 

[blade7]

ORIGINAL: pauljmcnulty

The correct tension is difficult to describe and can only really be guaged by feel

Or, there are two Porsche belt tensioners free to borrow for Club members... []

Or, you use the waterpump twist method that takes into account expansion of the block/head and doesn't knock out serviceable water pump bearings prematurely.

 

[pauljmcnulty]

Or, you use the waterpump twist method that takes into account expansion of the block/head and doesn't knock out serviceable water pump bearings prematurely.

Which doesn't sound at all technical to us non-experts! []

I use an indie, but if you want to DIY then the free (plus postage) loan of the gauge is there as an option.

 

[blade7]

ORIGINAL: pauljmcnulty

Or, you use the waterpump twist method that takes into account expansion of the block/head and doesn't knock out serviceable water pump bearings prematurely.

Which doesn't sound at all technical to us non-experts! []

I use an indie, but if you want to DIY then the free (plus postage) loan of the gauge is there as an option.

It's a while since I did it but from memory you set the cambelt tension using the auto tensioner and then back it off slightly so you can just turn the water pump pulley against the belt by hand, when the block/ head expand the belt gets tighter without loading the water pump bearing therefor extending it's life.

 

[RS2000CUSTOM]

Dont get too mixed up with cambelt tensions and balance belt tension

IMHO it is the balance belt and pulleys in most cases that produce the whine

 

[blade7]

ORIGINAL: RS2000CUSTOM

Dont get too mixed up with cambelt tensions and balance belt tension

IMHO it is the balance belt and pulleys in most cases that produce the whine

It's normal for a new balancer belt to whine slightly until up to temp, if the cambelt whines something is wrong.

 

[WXW611]

Belts fitted and adjusted by OPC still whines, I'd love to stop it. feel like giving it a smack.

 

[George Elliott]

OPC probably the highest risk workshop to let a car into. My 944t had the belt tensioner reversed by the last fitter (an OPC) when I looked in the history. I understand they sometimes don't actually change the belt, they just charge and say they did [8|]

DIY for me or a trusted indie.

George
944t

 

[WXW611]

I can confirm the belts were changed, I checked. I took it in after 3 attempts by indie to get the balance shafts in the correct position. They changed the chain tensioner pad, rocker cover gaskets and got the balance shafts spot on. The only thing missed was the idler sprocket which was half a mile away from servicing any useful purpose. the costs were reasonable and after being cancelled by another indie twice I was pleased to be able to take the car in the following day and pick it up at the end of the day. Bolton OPC have a beautiful 924 Turbo in the showroom which they have restored.