Replacing the Fan Belt..

[Ian W]

..so on the way home from finally getting my Z! fixed, I started misfiring horribly and kangerooing down the road, temperature gauge sky-rocketed, so I pulled over. Lifted the bonnet to find a shredded fan/drive belt! Presumed I was in danger of severely hurting her by trying to limp home so I got the car transported back home (by the same guys who transported it to the garage a day before - perhaps I should buy shares! )

So, firstly were all these symptoms simply connected to the belt going or do I have several issues to deal with?

Secondly, any help you can give to a novice mechanic on replacing the belt on a Z1, I'd be grateful for? (For example, do I need to remove the bonnet; radiator, etc? gulp! )

Thanks

[F.Brossaud]

Hello Ian,

This belt is not only the fan belt BUT the waterpump belt, that's explaining why the engine overheated !

In order to change it, it is not that complicated. No need to remove bonnet nor radiator.

- Remove the airbox + flowmeter so you can easily reach the alternator (2 bolts in wheelarch, behind the shorck absorber spring)
- Remove fan with 32mm big wrench. Be careful, thread is opposite than usual, so you will have to turn right to unscrew
- Loose powersteering pump bolts and remove the belt going from damper to pump
- Loose alternator bolts (one main at the bottom + the one on the tensionning plate) and then you will be able to change the belt going from alternator pulley to waterpump pulley.

Have a look here, it will be helpful
https://classicbimmerbits.com/e30-how-t ... placement/

Take your time and you will make it

=> The most important / difficult in this process is to never put your weight on the wing to not stress it and generate cracks later

[Ian W]

Thanks so much for the reply, I'm working away for a week but will give it a go when back home. Cheers

[Jet]

Don't forget both undertrays need removing.....which means wheels off. If you have access to a ramp use it, much easier, or try and get all 4 wheels off the ground.

I followed a similar E30 guide recently to change PS fluid and all auxiliary belts, but some steps are different its not 100% identical to the Z1. Do check the toothed tension bars, there are 2, if shredded worth changing, they cost about £20, and change both belts not just one. In my case, the PS pump bolt kept spinning, to loosen the rear nut was surprisingly difficult to get a socket extension onto, as the pipes are in the way.

Maybe its different on an E30, as I didnt need to remove the fan....

[Ian W]

OK, thanks for the info Jet, much appreciated

[Ian W]

Tried to send a vid but failed due to size, so will try and explain.
I've loosened the alternator so that it moves to the full extent of its track, did the same with the power steering pump. However, I move the pump as far it will go, approx 10/15mm, basically until it hits the underside of the alternator, but that doesn't give me enough to remove the existing belt. I could try prying yhe belt off with a screwdriver but I'm worried I'm missing something. Do I, therefore, have to remove either alternator or power steering pump in order to get enough movement to release belt...and if so which is easier? (I'm doing this from above as don't have access to ramp.) Or have I missed something obvious

[Green Genie]

Hi Ian
I had exactly the same problem on my way to Silverstone in 2014, I’m sure Jet will remember as I arrived past the entry time for my car to be put on the BMWCC stand. Jet made some arrangements for me with the organisers and the car went on display albeit past the entry time

My car did the same as yours and the temperature gauge was about to enter the red zone, but i pulled over in time so no damage done just the fan belt shredded. Im not overly handy with the spanner’s or had a tool kit with me so i called out the RAC.

The RAC guy arrived and saw the shredded belt and went off to get another, he also advised to replace the power steering belt at the same time. I don’t think either of the belts were Z1 specific, either way they are still on the car today! I’ll probably get them changed on this years service.

Jet is more knowledgeable and hands on than me on these cars but… the RAC man fixed mine at the roadside without taking off the undertrays or wheels, everything was done from under the bonnet. The whole repair (once he’d got the belts) took about 45 minutes from what I remember.

If you’re in the RAC/AA and you have home start why not give them a call? all it cost me as a member was the cost of the belts I did however give the guy a tip in cash

[Jet]

Hello Genie, how are you fella?

RAC man is right, it can be done from above, I opted for below to replace PS fluid, belts and avoid leaning on panels.

[TJS]

Couple of things to consider when replacing a fan belt

Make sure you have the correct belt. As pointed out there are two and one is slightly smaller and is not going to fit if you get them the wrong way round. You need the larger 9.5 x 965 belt not the smaller 9.5 x 900 power steering drive belt.

There is a toothed ratchet type adjuster for the alternator which will strip the cogs in the bracket if over tightened and prevent any adjustment when it comes to belt tension. I usually replace this bracket every second cambelt change along with the fan belt.

Realoem. “Altenator mounting parts”. Adjusting bar 12317677914 and the toothed nut “Idler”. 12317677914.

Replacement is doable from above the car, but easier from below if you have a ramp and the undertray fitting are in good condition and come off easily. If you have not replaced the front wheel arch liners yet they are likely to be very fragile and easily broken when removing and fitting the attached under tray. If so leave well alone and tackle the belt from above

[Ian W]

Thank you all so much for the time in replying to my various woes. My issue was indeed having too small a belt - what threw me is I'd ordered the right size and that's why I was stumped. I tried everything until as a last resort I measured the new belt and found it was a different size to what I'd ordered (and what was printed on it!) You can imagine the language emanating from my garage when I realised this! Anyhow, ordered another, checked it this time as soon as it arrived and what a surprise, it went on no problem at all

Once again thank you to all who offered their advice - much appreciated.

[TJS]

Good hear the issue is resolved. The confusion arises from BMW listing both belts as "Fan Belts" notwithstanding the slightly smaller belt is for the power steering pump.

Fan belt is 11 51 1 711 091 and the PAS belt is 32 42 1 711 067.



I replace both when the cam belt is changed and the ones that come off the car go into the spare wheel as emergency spares.