- My model of MX-5 is: __
- I’m based near: __
- I’m looking for technical help or recommendations on: __my Harvard drive belt off of the starter motor had perished, I’ve sold two now but both too big, can anyone advise on the correct size / part number please
Do you mean the Alternator? No drive belt on a starter motor
Start again with this.
Alternator belt = crank pulley - waterpump pulley - alternator pulley = 885mm 4 x ribbed belt standard.
I suspect the belt you are after is the 4 x ribbed power steering - crank pulley. I guess your car has power steering but no aircon so to cut to the chase an 860mm belt required. I think you probably bought the 885mm standard alternator belt by mistake? Given that the other one has perished, may be worth fitting one of those new alternator belts at the same time.
Autolink have good listings on their website for all these belts.
sorry yes, the alternator
thank you so much
These alternators are a right fiddle-di-dee to loosen off and belt tight.
You are permitted lots of tea, maybe a scone, and copious amounts of mouthed but unheard sweary stuff. 
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Brilliant lol, but I think my neighbors may be used to a few choice words. Thanks for the heads up though
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What I do is remove such part from Mx5, drive down to the local Motor Factors, slap such part on the counter and say I want one of these. John has a rummage around the store and eventually comes back and slaps a part down on the counter and says this is want you want. Sometimes Johns rummaging around a bit too long, so I switch on the kettle and make us a cup of tea for which he is most appreciative and if I’m lucky he’ll break out a pack of biscuits and we’ll have a little chat about our recent automotive projects which often results in myself buying tools and other parts I didn’t really need, clever salesman is John.
This is a much more pleasant way of buying parts for my car than going on a forum and asking for a part number that could be wrong.
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Given the nature of this enquiry and perhaps the chance that the belt is still in one piece, albeit broken, not bad advice at all:-)
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Alternator belt… Multi groove 4PK 885mm - Every 2 years /inbetween a Visual and tension check is recommend at service time
Power steering belt without A/C… Multi groove 4PK 860mm - Every 2 years / inbetween a Visual and tension check is recommend at service time
A/C without power steering… Multi groove 4PK 860mm - Every 2 years /inbetween a Visual and tension check is recommend at service time
Power steering and A/C … Multi groove 4PK 948/950 - Every 2 years / a Visual and tension check is recommend and service time
Timing belt… Length: 45.67 (in), 1160.00 (mm); Width: 0.87 (in), 22.00 (mm); Number of Teeth: 145 changed every 6 years or 60,000 miles which ever arrives first with the water pump also
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The power steering belt/A/C belt? needs to be removed first then the alternator belt, the hinge bolt on the 1.8 and all NB’s can give issues because it is directed from the back to the front and is tightened up into the front threaded arm of the alternator which is exposed and fuses together , simply slacking the locking block and turning the adjuster/tensioner bolt right right out and pulling upwards on the belt should pull the alternator in to be able to remove the belt, there should be no need of the internet stress knowledge of getting her on axle stands, removing the under tray ,snapping bolts and nuts as you go to slacken the hinge bolt with a spanner and jack from, although we highly recommend swapping it out for a MK 1 1,6 version nut and bolt fed from the front and will never give you any hassle again, simple satisfying conversion to do ,to make service time just that little easier for good …Shout if we can be of help…
http://www.mazdamenders.net/forum/viewtopic.php?f=125&t=6872
M-m
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I would say from my experience an auxiliary belt should last 6 - 10 years.
Certainly the life of these belts is considerably less, down here in sunny south Devon than in my previous abode in Coventry. Once set up properly a belt should be fine until it needs replacing. At the stage a belt reaches the age where it needs adjustment or shows demonstrable signs of perishing/damage, replace it.
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Every two year , they are pennies to change and do.
M-m
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