- My model of MX-5 is: __NB 2.5 Arctic 1.8
- I’m based near: __Tenbury Wells
- I’m looking for technical help or recommendations on: __squealy fix
I’m teaching myself car maintenance by doing things to my rusty old NB……. 
Completed basic service, oil change, air filter, new plugs and seems to have gone OK.
Now I want to address squealy belt on start up, my guess is alternator belt as it seems worse when there is electrical load. They will definitely need doing as previous owner did few miles but also minimal maintenance so I am going to want to change them.
So I need to whip off air intake pipe, remove power steering and alternator belt (so might as well change this too) and then access alternator belt via . I plan to do on my drive - I don’t need access to underneath do I? Haynes describes the job as “fairly difficult”, I guess because of awkward access.
I don’t own a belt tension measurer so was planning to do by ‘eye’ …
Any helpful tips or thoughts on whether OEM have any advantage over non-OEM belts …. ? Was planning to get them online from MX5parts.
Cheers big-ears!
C
You may want to get under the car, or at least remove the offside front wheel to get better purchase on the alternator pivot bolt. It’s awkward to reach, especially if it’s very tight and you need to get a ‘good’ angle on it. Removing the inlet manifold brace can help with access too.
I don’t know anyone that does own a belt tension gauge. Do it by feel. If it’s a flat belt (rather than a Vee belt) you should just be able to twist it through 90° by hand in the middle of the longest run . Check the tension of the existing one to get a feel. If it’s squealing, it isn’t tight enough, anyway.
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Thanks for the advice - I do have access to a pit so, instead of being lazy, I might go there just in case
C
I did this on mine not too long ago. You don’t need a tension tool of any type. When tightening the belts the key thing to remember is that when you take the belt between your index finger and thumb you should not be able to “twist” the belt more than 90 degrees(IE: stand it on edge but no more) between the pulleys. The alternator belt you will need to get under the car to be able to loosen the locking nut on the back/bottom. The other belt you can get from the top. This is not a difficult task by any means….but since getting under the car is required, make sure you have jack stands under it, its way too easy to knock a car off a jack by accident.
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I always approach the alternator pivot bolt from above, use a decent length 14mm combination spanner, use the ring end with the shaft of the spanner angled towards the front of the car and pull up. There is a plastic splash shield on the chassis leg that can be removed to improve access. The bolt will be tight (read seized), loosen off the adjuster first and then as you pull the pivot bolt up the alternator will move inwards increasing access further.
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Thanks for the helpful advice everyone, I went online and bought the Gates Micro-V belts as my friend Grok recommended them
I’ll have the pit available but hoping i’ll be able to get a ratchet spanner or something on alternator bolts from upstairs
C
The problem is that the lower alternator bolt locks from the back…not the front, the bolt head is on front, lock nut on back(at least on my US-spec NB). It’s possible to get to it from above…but not worth the effort when you can take 2 minutes to get a jack under the front subframe.
On the OPs engine, the head of the bolt will be at the back. There will be no nut, the aluminium alternator casing is threaded where the bolt goes in. Steel bolt, aluminium casing, they seize in…
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OK, I bit the bullet and did the job today, took me a couple of hours but I was taking it slowly. Thankjs everyone for the advice
The existing belts I removed weren’t actually in bad condition but were of uncertain age, the alternator one did have slight cracking starting on the inside rubber. On a cold start it was squealing a lot, especially with any load on the alternator.
The job went OK except accessing the rear alternator bolt everyone warned me about, it was tight but I managed to shift it with a ratchet spanner, did some minor damage to my forearms, not as bad as the oil filter though, that sliced up my forearms quite badly.
Hopefully the squealies will be gone now, I can always re-tension if needed!
Next jobs
- Squeaky clutch
- Fuel filter
- Cam belt, water pump etc
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