13 replies to this topic

[MrRussells]

Hi all

I have looked through the forum and I am wondering if there is a guide to changing the fanbelt. The old one snapped, I have seen a video where you feed it over the fan but that isn't making sense to me.

Any tips on doing this?

I feel silly and frustrated for not being able to fix it.

[MatthewsDad]

Hi you just need to loosen the alternator bracket and allow the alternator to droop, thereby creating slack in the belt. Then it's a case of unhooking the belt from the alternator, fan and crank pulleys, and gently weaving the belt gradually around each blade on the fan. A bit tricky but you can work the belt between the fan and radiator this way.

Edited by MatthewsDad, 14 April 2020 - 07:02 PM.

[dmandan]

I had to remove all the bolts from my alternator, the rotate it so brackets cleared the block gave me an extra few MM of clearance to get the belt on.... it's a bit fiddly but you can work the belt between the fan and the cowling

[MrRussells]

OK so I have the belt on, its over the fan and I have it around the waterpump and crank pullie but its about half a cm too short to go around the alternator. This is pivoted as much as it can towards the engine. I was able to get the old one off this way.

The belt is the same size 825.

Is there something I am missing short of removing the alternator completely?

Thanks for you help on this. Noob mini owner

[MatthewsDad]

If you still have the old belt line it up with new one on a flat surface to check they are identical lengths. Even a small difference can cause problems.

[humph]

Is that this belt then?

 

http://www.minispare...|Back to search

 

Perhaps you may be better off with this one, that extra 13mm will make a big difference.

 

http://www.minispare...c/GCB10838.aspx

[sonscar]

If it will start to go onto the pulley hold it and guide it on whilst turning the fan,sometimes it works and then you can marvel at how slack it now is.Good luck,Steve..

[dmandan]

Be very careful when it's back together and tensioned that the cooling fan blades behind the alternator pulley (probably not what they are really called) dont hit the grill panel like mine did, makes a right mess !

[MrRussells]

Hi all

Thanks for your help. It turns out even though I have an 1994/5 SPI the fanbelt length is 838 rather than 825.

Lot of time wasted but now I know.

One ordered so thats given me something to do Tuesday evening :)

[[email protected]]

I've seen cases where an older belt (and somewhat stretched because of age) was used as a "quick fix to prep for sale", which allowed it to fit where only a longer length factory-fresh belt would have.

 

If you have a log book, I recommend noting the size you'll eventually settle on as the right fitment for future reference.

 

We shouldn't leave this post without some recommendations so the OP can get the belt tension correct!

 

I've seen where some folks recommend stop lifting the alternator just when you get a certain amount of deviation across a certain span (different deviation measurements between alternator-to-water pump span OR alternator-to-main pulley span since those two lengths of belt differ); while others recommend where you can just twist the longest span 90 degrees along its length by "twirling it" between your fingers (imagine rotating a pencil a quarter turn between your fingers like you are rolling a log).

 

But I'll leave it to the more experienced folks in the forum to post some more solid recommendations on judging tension or to post links to previous posts that explain it better than I could from my phone.

 

I'll just warn that too loose and you can prematurely glaze the new belt and not get good charging. You'll know it's too loose if you can easily spin the fan with a single finger's pressure (when the engine is NOT running, obviously! - see example video where an old belt had been stretching over time here).  Also if you hear a squealing noise when you turn on all your lighting with the engine running - that is the belt slipping - some recommend squirting some water in the belt when running to "highlight" any slippage).

 

More importantly, too tight and you'll ruin your water pump bearing or seal and you'll have a much bigger job on your hands! (Hence my feeling the need to comment about getting the right tension because that had happened to me!)

 

Good luck!

 

PS: how are folks getting at the lower locking/positioning bolt on the alternator without first removing the grill? I don't see any mention in the post re: removing the grill first... but I always have to take mine off in order to get into that fitting...?

Edited by [email protected], 19 April 2020 - 06:38 PM.

[brivinci]

I always have to take mine off as well. Its just very tight. 

 

Has anyone tried any sort of emergency-type belt before? I do not always carry tools OR always want to be doing roadside work on the car. Would be awesome to be able to use something temporarily to get you home to to somewhere where its safe to work on the car.

[MrRussells]

All back up and running. Thanks for all your help. That is one fiddly job.

[[email protected]]

I had never heard of the "emergency" fan belt before Brivinci!

But I think I found what you are talking about here...

https://www.royalsup...6112-p91817.htm

This site seems to have some photos of the assembly mechanism and it looks like you need to turn the tab end 90 degrees to fit it through the other end:

https://www.amazon.c...B6G/ref=sr_1_28

...so it certainly seems like it might allow one to avoid having to squeeze past the fan blades & the radiator face...

...but I suspect that...

A) you'd want to "pre-size" it when it first arrives (because looking for your severed fan belt over the last quarter-mile of road after it snapped in two to get the right length wouldn't be all that much fun!)

and

B) unless there is some amount of elasticity to it, it looks like it would be difficult to fit the "locking tab" in place - under the right amount of tension - because of the need to turn one end 90 degrees while you are trying to have the emergency belt stay fitted in all three pulleys...

So it seems like it would be just as impossible to pull a right-sized emergency belt over the lip of the final pulley once the belt is assembled to the correct length as a regular belt is without freeing up and dropping the alternator...

It doesn't seem like fitting the master link on a bike chain where you could actually do it while the chain is already on the sprockets...

So I'm thinking that if you are going to have to get in there to loosen the adjusting fitting below the alternator anyway, then the process of slipping the belt past the fan/radiator feels like the least time consuming part of putting either an emergency belt (which only skips that part) versus putting a proper belt in.

Does that make sense seeing how this brand of emergency belt is constructed, or am I missing a trick here?

This seems more a useful "spare part" tool for a road service mechanic who comes upon a variety of cars and doesn't want to stock a hundred different length belts in his kit.

Edited by [email protected], 24 May 2020 - 02:34 PM.

[brivinci]

The reason I asked is really due the fact that I am running a Cooper S, 2-piece dampener now. They are taller and there is barely any clearance between it and the bottom of the timing cover breather. In order to get a belt on, you basically have to remove the pulley! Not ideal. Got me thinking about what would happen if the belt snapped out in the middle of nowhere. 

 

I agree with you on all questions. It would have to be pre-sized and I can not see it working without adding tension by adjusting the alt...but if you can do that, you can just replace the belt with a correct one. 

 

As my motor is currently out, I decided to finally modify my timing cover breather and lop off a bit at the bottom to allow for a bit more clearance so now a belt and get around it. Its still not a job I'd love to have to do on the side of the road but at least now its doable.