crank pulley damper and lockwasher

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cyrus
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crank pulley damper and lockwasher

Post by cyrus »

Hi I have got a crankshaft damper pulley off an A+ series which I want to fit to my late saloon. Drilled the rivets off and removed the timing ring. I want to keep the starter dog, can I use the standard lockwasher on this pulley?
Also on the subject of fanbelts I have had a new fanbelt on the standard pulley for a few months now and it never seems to stop stretching, I am continually adjusting the thing. It is the serrated type, I kept the old solid belt as a spare but am thinking of swapping back as the old belt was stable and rarely needed adjustment. Is this a known issue with some modern replacement belts?
philthehill
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Re: crank pulley damper and lockwasher

Post by philthehill »

You can use the standard crankshaft pulley lock washer. You just have to knock one part of the washer down into the indent in the front face of the damper pulley. The other as you will know already goes up against the flat of the starter dog.
Crankshaft damper 1.jpg
Crankshaft damper 1.jpg (48.88 KiB) Viewed 492 times
I am not aware of any problems with the serrated type of fan belt. Perhaps others may have a different experience.

simmitc
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Re: crank pulley damper and lockwasher

Post by simmitc »

Re the belt stretching - is it the belt, have you measured it? It could also be a pulley opening out or simply the generator closing up due to ineffective tightening of the clamp (not suggesting that you've done it wrong, rather that the components might be worn).
cyrus
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Re: crank pulley damper and lockwasher

Post by cyrus »

Thanks for that Phil thought it best to check. Yes that is exactly the damper I have. Looking forward to seeing what effect the damper pulley will have.

simmitc - the nuts and bolts are all tight and never had this problem before with any other Minor - will check the pulleys. The old "solid" belt was completely stable for long periods on the same car. Haven't measured the belt will probably swap the pulley over and look at pulleys and belt then.
many thanks
Tinasminor
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Re: crank pulley damper and lockwasher

Post by Tinasminor »

What is the advantage of fitting a damper pulley?
Cheers Steve.
philthehill
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Re: crank pulley damper and lockwasher

Post by philthehill »

Fitting the damper pulley to the 1098cc engine helps remove any harmonic imbalances in the engine, The 1098cc engine is not so smooth as the 948cc engine. Fitting the damper to any 'A' Series is a good move,

Tinasminor
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Re: crank pulley damper and lockwasher

Post by Tinasminor »

Blimey, you learn something new every day.
Cheers.
philthehill
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Re: crank pulley damper and lockwasher

Post by philthehill »

There are at least five different dampers that can be fitted to the 'A' Series.
The dampers should ideally be tuned to the harmonic imbalance range. The 1275cc Cooper 'S has a totally different harmonic damper which is produced in two pieces and is of a size and dimension to suit the harmonic imbalance of the 1275cc engine.
The harmonic damper can be tuned to suit the harmonic imbalance of a particular engine which usually involves reducing the weight of the damper.
The harmonic damper was introduced by BMC/BL to improve crankshaft longevity. At one time BMC/BL crankshafts went through a period of unreliability with the cracking and breaking of the crankshaft where the web met the journal especially after introducing the rolled fillet.
Rolled fillet 2.jpg
Rolled fillet 2.jpg (44.2 KiB) Viewed 398 times
Rolled fillet.jpg
Rolled fillet.jpg (32.88 KiB) Viewed 398 times

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