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 Post subject: Crank Pulley - Alternator Drive
PostPosted: Fri Feb 03, 2017 1:59 pm 
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Afternoon all

By a process of elimination I have deduced I need a new crank pulley for the alternator drive belt. When the car is out in moderate to heavy rain (parked that is), on start up the crank obviously turns but the belt does not. Voltage stays at 12v, basically battery power, then after a few seconds you hear a screech as the slips minimises then it stops and normal operation resumes, showing 14v on dash. Same effect can be had by driving through large puddle. So basically my crank pulley is disintegrating, albeit slowly. When you take the belt off there are slithers of metal from the pulley stuck inside the grooves. This can sometimes make for unpleasant noises as you can imagine. I have ruled out the alternator pulley as have had several alternators and always been same. Have also replaced AC compressor so the pulley on that is not at fault. Plus it has to be the crank pulley anyway as this is where the drive is initiated.

Anyway, I see this connects to the balance belt drive via 4 allen head bolts. No dramas. Does this then slip over the PS pulley or does it need removed also? And if so is that the bolt at a million NM that is often discussed or does it simply hold on the PS pulley??

And to finish, OPC want £96 for a new pulley. Do any of you fine chaps have a new, or good serviceable item you could swing my way for beer tokens? Part no. 944 102 116 12

Edit to add: belt is not slack!!

Many thanks in advance

Stuart

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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Fri Feb 03, 2017 4:50 pm 
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There is a rubber sandwich between the inner and outer Stuart. If the pulley can be seen to wobble, the rubber is knackered. The big bolt in the front needs to come out to get the PS belt pulley off and then the ribbed belt pulley is removed after the 4 5mm Allen headed bolts are removed.


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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Fri Feb 03, 2017 7:27 pm 
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Cheers Al. There's a little wobble on the PS belt but that is OK. It seems to be the metal stripping off the alternator belt pulley that is my issue. So would like to replace that. Will change the rubber bit when I'm in. So to confirm the bolt for the PS pulley only holds the PS pulley? It doesn't secure anything else?

Cheers

Stuart

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'90 944 Turbo - Sunroof delete, Factory bridge spoiler, CS wheels, CS steering wheel, 1st MY90 turbo in UK

Promax L2 chips, SciVision MAF, Lindsey DPW, MBC, Forge recirc valve, 3 bar FPR, K&N panel, GAZ Gold, wideband AFR, Sytec Motorsport Fuel Pump.


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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Fri Feb 03, 2017 8:45 pm 
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Interesting. I have a wobbly pulley which I put down to it being clonked when the new motor was installed. Also had the occasional screech when wet. Fords do it all the time round here. Nice to see you posting again Alisdair :D

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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Sat Feb 04, 2017 9:42 am 
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There shouldn't be any metal shavings from the pulley so something is not right doen there. The PS pump pulley may be a bit out of round or not seated properly.


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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Sat Feb 04, 2017 1:38 pm 
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It's the alternator pulley though. PS belt and pulley seem fine although slight wobble.

I genuinely think the metal surface is stripping off the alternator pulley. It's very odd. I notice though the current part number ends 12. And that the original ends 10. 11 superseded that and then 12 has superseded 11 which leads me to think there is a reason why a new part has been commissioned twice?

Puzzler

Stuart

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'90 944 Turbo - Sunroof delete, Factory bridge spoiler, CS wheels, CS steering wheel, 1st MY90 turbo in UK

Promax L2 chips, SciVision MAF, Lindsey DPW, MBC, Forge recirc valve, 3 bar FPR, K&N panel, GAZ Gold, wideband AFR, Sytec Motorsport Fuel Pump.


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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Sat Feb 04, 2017 7:14 pm 
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Would really need to see it.


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 Post subject: Re: Crank Pulley - Alternator Drive
PostPosted: Sun Feb 05, 2017 11:27 am 
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No worries. I'll grab you when your free if that's OK.

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'90 944 Turbo - Sunroof delete, Factory bridge spoiler, CS wheels, CS steering wheel, 1st MY90 turbo in UK

Promax L2 chips, SciVision MAF, Lindsey DPW, MBC, Forge recirc valve, 3 bar FPR, K&N panel, GAZ Gold, wideband AFR, Sytec Motorsport Fuel Pump.


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