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Discussion Starter #1
I did the cam belt and tensioner a few months ago but was never happy with a kind of whining noise coming from the belts area. Some people told me these engines had a tendency to whine after a new belt so I left it for a while to see if it died down. But it didn't. At first I thought it might have been the auxiliary belt, but when I removed it, there was still a definite whine. So off with the covers and the balance belt - sure enough, the whine was gone.

I took some care in refitting the balance belt, lining up the white marks on the belt with the marks on the pulleys etc (though I can't for the life of me think why that might be useful unless for some timing light action). Also, and this is probably where I went wrong last time, I was precise in getting the two balance pulleys lined up properly. I don't remember taking all that much care when I originally put the balance belt on, so I guessed this was my issue.

Sure enough, the engine is now running like a clock, whine gone. It seems that if the balance shafts are not exactly where they need to be when No 1 piston is at TDC the engine doesn't like it.

Anyhow, the top tip. I was really struggling to properly tension the balance belt tensioner pulley. I've got the right tools etc, it's just that you need to be an acrobat to hold the tool on, rotate it, check the dot on the tensioner is exactly in the middle of its travel and then tighten the 10mm nut behind. After an hour I was chucking spanners around the drive.

The solution is to support the engine on a jack, and remove the major obstruction, which is the drivers side engine mount. Three RIBE bolts and a 19mm bolt into the wing mount and off it came. After that it took literally three minutes to tension the balance belt properly. The mount isn't difficult to remove or replace and it makes the whole job so much easier.

Anyway, thought I'd mention it in case it helps someone.
 

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Thanks, My own tip: Don't. Just leave the balance belt off. Too many stories of the belt failing and taking the timing belt with it. I inspected the timing belt on my GTV not long after I bought it as it had a new timing belt and found the brand new balance belt snapped under the cover. The bearings can wear which is an engine out job to replace and not touching them can introduce a knocking noise.

Not all 2.0tsparks can get away with this but the vast majority of them can be removed without ill effect.
 

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The white marks on the belt and the pulley marks have to be matched other wise it'll be an anti-balance system.

The belt whine would have been because you had the tension too high - it can be a bit awkward to set as you say.
 

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Discussion Starter #4
The white marks on the belt and the pulley marks have to be matched other wise it'll be an anti-balance system.

The belt whine would have been because you had the tension too high - it can be a bit awkward to set as you say.
I don't understand why having the belt positioned at a certain point on a pulley would make a difference to the balance. Surely the belt is the same weight all the way around so positioning it won't make a difference. but lining the marks up with the notches on the pulley would make it very easy to check timing with a lamp, I'm guessing? Assuming of course the balance belt was fitted at TDC on the bursting stroke, with the balance pulleys all in the correct position. I think that the positioning of the pulleys is the key element in all of this, so that the balance shafts are turning in precise coordination with the crankshaft. Maybe the white marks are intended to enable precise alignment with the guide marks on the engine behind the pulleys.


Anyhow, big improvement in the sound of it now.
 

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The belt itself has no effect on the balance, it's just there to turn the 2 eccentrically weighted balance shafts which counter the engines natural imbalance. To do this the shafts need to be timed perfectly to the crank, hence the marks on belt and pulleys.
 
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