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Hello all,

I have a noise coming from the front harmonic balancer...looks like it is rubbing.

The clutch (pulse)vibrates as I am taking off...

Is it possible I have bent my crank?

Or have I a faulty harmonic balancer?

New harmonic balancer fitted 12 months ago.

Cheers

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yes it could be a bent crank. if you put the car on stands and start it you would be able to to see the balancer move - even 1mm is bad news. or to be more accurate, pull the balancer off and check the run out with a dial gauge.

we had a 33 with a bent crank, the nose of the crank was only moving by .1mm or something like that but it still flogged the bearings out.

why did you fit a new balancer? And are you certain the balancer bolt is tight?

Thanks for the reply,

I had front seal problems when I first got the car.

Had the seals changed 3 times until I suspected the oil pump.

Sure enough after the pump was changed no more problem.

The balancer came off and then put back on a few times.....causing the key to break

and cause my balancer to chip.

We replaced the Balancer last year this time....everything is still tight.

My workshop has not pulled it out yet to see what the problem is...but am suspecting the worst.

How did you fix the problem?

you really don't want to know ;) full rebuild, new crank and probably new block as well because it really flogs out the bearings and tunnel.

given that you have had seals, balancers etc damaged, it really does look like you had a bent crank all along. get the workshop to check with a dial gauge, but they really should have checked it already given the number of problems you have had

  • 2 weeks later...
what exacly was wrong with the old oil pump?

The pump had been punished by the slightly bent crank all along.

Might have worn the side walls near the seal.

.

Anyway...thats ok now...cause engine re-build time ;)

Was knowing it would come to this...just not knowing how soon.

Crank bent, .7mm out ..tried a second hand harmonic balancer to make sure.

Hope I don't need a new block.......would love to use mine.

block should be OK but will need to be checked out. It might require a tunnel bore to be straight again

Underway as we speak.

But am going 86.5mm Pistons so bore and hone.

Thanks all for your input. :nyaanyaa:

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