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Oh, hai!
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How to: Replace Auxillary Belts

Please read this guide in its entirety before picking up any spanners. Skipping ahead or rushing could cause you problems further down the line.
Please also note that this was carried out on a '95 1.8 Eunos. Items may differ on earlier 1.6s or later Mk2/2.5s and depending on trim level.
Where possible, I have commented on possible differences.

Good afternoon Nutzers. I've just been out and swapped my auxillary belts over and I took some pictures whilst doing the job. It's rather simple but I thought a tutorial might be handy for those who aren't all that mechanically minded who are looking to save some beer tokens by doing work themselves.

When do they need changing?
Aux belts are quite hardy things and generally don't need replacing all that often. I'd suggest changing them whenever they have to be removed to do another job or once every year or so. Just keep an eye on them to see how they're fairing.

If your belts look like this...


...they're ok and won't need replacing for a good few thousand miles. Keep an eye on them though, they can deteriorate quickly and squealing indicates they're becoming slack and will only speed up their deterioration.

Also note that early 1.6 engines use a plain alternator/water pump belt rather than the poly-V ribbed belt shown above. (Thanks Niggle for the additional info)

If they look like this however...


...they're utterly fucked and need replacing ASAP!

What you will need
Replacement belts (MX5parts.co.uk are about the cheapest, although it would pay to check your local motor factors)
12mm socket/spanners
14mm socket/spanners
Ratchet
Socket extension bar
Phillips head screwdriver
Pliers

What to do

Yuki is a 1.8 Eunos with power steering and aircon, so that belt has to come off first. Some earlier cars or those of a lower spec might not have the 1st belt which will make the job easier. But anyway, you should be greeted by something like this...



Now, unless you have a small Japanese man spare who can fold his arms into origami swans to get past the crossover pipe, you'll have to take it off.

Mk1 1.6 owners should note that the crossover pipe is virtually impossible to remove without removing the radiator top hose first. You will probably have to struggle with the crossover pipe in place but disconnect it from the inlet manifold and MAF to allow it to move around a little for a little bit more access to the alternator pivot bolts. Either way it is best to cross-match a couple of units of blood first, to replace that lost from your knuckles whilst doing the job. (Again, thanks for the info Niggle)

I have an aftermarket airfilter, but everything up to the screw band marked should be the same on yours, even if you're still running a stock airbox.




Once unscrewed, the airfilter/airbox should just pull off the pipe. There's no need to unbolt if from the car or disconnect the airflow meter, but you can if you feel inclined to do so.

Next, undo an identical screw on the otherside of the crossover pipe which connects it to the throttle body...



You will also need to disconnect the vacuum pipe (left arrow) using a pair of pliers on the spring clip, and the rocker breather pipe (right arrow) by pulling it off.



Once disconnected, the crossover pipe should just pull out of the engine bay, leaving...



And the belts... (Ignore the rusty stains, Yuki has been leaking which is why the belts were coming off)



To remove the belt, you first need to slacken the tension. On top of the power steering pump (top most pulley/pump) you will find the adjustment mechanism...

(Excuse the crossover pipe being in place, the picture I took with it off was out of focus and I didn't realise until I'd finished the job)


#1 is the retaining nut. #2 is the adjusment nut. Undo #1, then undo #2 all the way. It doesn't matter too much if the bolt comes out, it's easy enough to put back together. There is also a second retaining nut that will need to be undone. It has to be accessed through the holes in the pulley. To get the power steering pulley lined up to access the nut, put the car in 5th gear and push it forwards/backwards. (Thanks to Indykid for the tip)




Once all three are undone, the pump should drop down (it might need some gentle pursuasion
) and the belt will be slack enough to remove it from all three pulleys. For those with only power steering, this will be slightly different due to only have one pump to contend with. It's also important to make sure you order the right belt as the non-aircon power steering ones are significantly shorter than those with aircon.

Once the first belt is off, it's time to work on the alternator. This has an identical adjustment setup to the other pump...



Again, #1 is the retainer, #2 is the adjustor. Undo both. There isn't a second retainer bolt on the alternator (at least, I didn't see one!) so you will need something to use as leverage to move the alternator enough to get the belt off. It will probably have to go as far in as possible to get the new one on.

EDIT:- There is a third retaining bolt, it's at the rear of the alternator. It's a bit tricky to reach, but behind the alternator and at the bottom, engine side, there's the nut. You can get it from the front with a 14mm spanner if you reach under and up behind it. But if you've never loosened it before, you may well find you can't get enough leverage that way to crack it loose. In that case you can take the manifold support strut off (3 bolts) to get a socket onto it. (Thanks to Martin Y for the information.)

Once you have the new belt on the alternator, water pump and crank pulley, do up the adjustor on the alternator until the belt is tight enough. It should not be possible to twist the belt more than 1/4 turn across it's longest span, which is between the alternator and the crank pulley. Once it has been adjusted and you're happy, do up the retaining nut. The same applies to the second auxillary belt if you have it fitted, remembering to do up the 2nd retaining nut through the pulley once correctly adjusted. Again, 1/4 turn across it's longest stretch.

Once done, it should be something like this...



Fin.
 

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Rollin' on 15's, baby!
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Nice one!


Mk1 1.6 owners should note that the crossover pipe is virtually impossible to remove without removing the radiator top hose first. You will probably have to struggle with the crossover pipe in place but disconnect it from the inlet manifold and MAF to allow it to move around a little for a little bit more access to the alternator pivot bolts. Either way it is best to cross-match a couple of units of blood first, to replace that lost from your knuckles whilst doing the job.

Also note that early 1.6 engines use a plain alternator/water pump belt rather than the poly-V ribbed belt shown above.
 

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Any colour, as long as its black.
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Urgh, this reminds me I need to do mine. Its squeaking like a deranged mouse right now
How long did it take you?
 

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Oh, hai!
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Discussion Starter · #5 ·
Urgh, this reminds me I need to do mine. Its squeaking like a deranged mouse right now
How long did it take you?
Took me about an hour or so in total, although that was figuring out what bolts to undo as I wasn't following a Haynes manual, and also taking pictures at each step.
 

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Happily expanding the To Do list since 1997
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Very nice work.

The only thing I'd add is that the alternator is a lot easier to move if you loosen the nut on the long bolt it pivots on. Kinda tricky to reach, but behind the alternator and at the bottom, engine side, there's the nut. You can get it from the front with a 14mm spanner if you reach under and up behind it. But if you've never loosened it before, you may well find you can't get enough leverage that way to crack it loose. In that case you can take the manifold support strut off (3 bolts) to get a socket onto it.
 

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Really great stuff, I have been meaning to ask about this


Now feel like it should be no problem to do.

Cheers
 

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Oh, hai!
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Discussion Starter · #8 ·
Really great stuff, I have been meaning to ask about this
Now feel like it should be no problem to do.Cheers
No worries. And that's the idea of the FAQ. Not everyone had the knowledge/confidence to attempt maintenance on their cars. It doesn't really slow me down much taking photos and if doing that and taking some time to write a guide helps a few people save some beer tokens/get their hands dirty then it's all worthwhile.
 
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