Idler Belt pulley for alternator

Have been trying to remove the belt tensioner to replace the belts but the nut doesn't seem to want to budge.
I would like to replace both belts it's AC version.
What I want to know is do they often prove hard to remove. Being a 14mm nut as far as I'm aware. So I'm going to get a spare one incase I have to use brute force.
Lastly what i want to ask is, do the bearings ware out and would it be heard if they are ready to be replaced.
Might try to replace just the bearing if that's possible.
I am changing my timing belt, water pump, and alternator/ac belts including all pre tensioners. As my engine is diesel it a different set up, however the process is similar in that you best warm up the engine before you start the heat will help with the bolts attached into the engine, also make sure you have 6 pointed impact sockets and knuckle adaptor if needed. approach the Job with the correct tools or you could create a nightmare for your self. dont rush and use plenty of pentration oil to hand.:unsure: lasty all bearings wear out but stick to german or swedish made bearings and you will not go wrong.
The way it's designed cannot get a socket on. I do have some crows foot adapters that I may try. Also another I was going to try was a longer wrench.
And yes I was attempting on cold engine last time.
With spanners that are not 6 point I used to have a great selection and now I'm using modern rubbish.
And yes I had a near escape with cheap parts but decided I would wait to see what is left of the ones I have first.
I'm looking forward to trying out the new tool as well when it arrives even if it only gets used for the wheel removal and a few other things.
I would have just done without but since trying the copy makita impact I decided it was time to get something with actual heavy duty torque.
With regard to the tensioner bolt though I have a few options 1 being those crows foot that are closed end almost fully but clearence may be issue.
Option 2 use the crows foot and tap with something.
Option 3 try get a removal socket on and use bigger wrench.
Option 4 just tap at the nut with the cold chisels and hope it breaks free then replace.
I'm guessing if I warm the car up it will be okay tho with regular.
After looking at what causes this problem for me tho I think I found its a good idea to just try different wrenches and see what fits best because sometimes is alot of play even with new ones.
If only it were simple as put the 6 sided socket on that would be nice.
Hard to access areas are a real problem, I crushed a finger many years ago using crap tools and decided to stay clear of cheap tools better to wait than cause injury or ruin the job at hand, I have my front bumper and headlights removed to make access easier, as the Micra is laid up for winter now. but be VERY careful with the air con unit's pipe if they present a problem find a tool or device that can access the area without disturbing them.
They are not cheap tools just they don't have 6 point closed end I have two different sets. The multipoint spanners seem to be most popular here in UK and are fine most of the time.
If it's possible to remove from above I will give that a try also although I'm not sure if that is possible.
I will be taking as much time as I can with this and to wear gloves that are padded to avoid injuries.
The tool that I felt would help me the most are the crows foot flare wrench ideal for moving the position of the ratchet or breaker bar back away from the area roughly 1 inch at most.
The pulley head can be replaced quite easily, this includes a new bearing pressed into the pulley wheel, as this part takes the most load and movement, this should be ok to renew for now, the auto tensioner is quite sturdy and designed for long service, when you remove the pully head spray some lubricant onto the spring loaded part of the tensioner.Any bolts that are removed I measure and replace with either 10.9 or 12.9 tensile strengh bolts preferable zinc coated from an Industrial supplier, then apply a little copper grease to the threads before assembly.:)
Tried a few goes and it rounded off so I had a go with a bolt removal tool they are not working.
Then tried the nut splitter can't get it on properly.
Had a go with a cold chisel and still unable to loosen it off.
Only other option is to heat it up as a last resort.
For now tho I've put the wheel back on because I've had enough for today.
The other side looks like it might loosen off easy.
So I'm going to just have to buy a new one and go with heating it up and that was something I did not really want to do as heating it up will definitely ruin the bearing.
The heat might work but ain't much left of the bolt to hold onto now after hours of trying every different method I could think might loosen it off.
I did warm the car up well before starting also.

Next time I'm going to use electric heat gun and cover the surrounding area the just heat at the nut and see if it works.
In the mean time I will find a suitable replacement part.
Pretty annoyed that the car always seems to win with the same old story.
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Check the direction of the pulley as if the direction is anti-clockwise then it may be the bolt is a left hand thread! ( so the bolt tends to keep tight when under rotational stress) similar concept to one of the pedals on a push bike which is left hand thread. Also a heat gun is too broad a heat band, you really need a oxy acetylene torch (narrow heat point). I have had stubborn bolts and have ended up having to drill the head off the bolt, remove the pulley mechanism and then you will have access to the remaining bolt thread. You will get problems to overcome frequently in life, but will power and determination to succeed will prevail.:unsure:
After watching other remove this on a nissan note and one on micra it was anti clockwise turn.
I was trying that way because that is the usual when a bolt is facing towards me sometimes they are reversed tho for certain items that require this.

I'm going to use the cut off tool. and just cut down the bolt. Until it cuts through the nut. Should this cut in easy it will cut right through. Then if not it will make the nut easy to remove.
I have not tested this before but is a good method that requires little effort.
I think I can get in and do this because I have a flexible extention for the cut off wheel.
Saftey goggles are the ready.
This is what I will use I've had some before by silverline and they shatter these look more robust like a grinder disc they are 38mm so that may be a slight problem for clearence although as long as it cuts doesn't matter if it's central or just to the bolt.
They look stronger but are alot more expensive in my opinion. They will cut through bolts tho for sure.
Its that or the gas torch.


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That should help you, lots of times its easier to chop off the heads of bolts etc than trying to deal with corroded nuts and bolts. good luck with your project.(y)
Once removed, I shall measure them and although the other side looks fine I will replace that nut.
Since they seem to be made of a really soft metal that does not help with removal.
Some thing I noticed when working on this after looking at a few guide some were saying 13mm and others 14mm it definitely was 14mm on mine tho.

So I need to check belt direction to determine the direction of the bolt thread.
Possibly this is reversed if someone mistakes the non air con for the air con version of the pulley as that is the only difference.
To be honest I didn't check that but had seen one person marked the belt direction because he was only replacing the pulley and not the belt.
That was so the belt could be replace in the same direction.
While waiting on the pulley to arrive still.
The speed click has arrived they are great but might be hard to get in.
Found this recently and have some metal cutting discs for angle grinder that are new.
This will work very well.
Image is of cut off shattering biscuits not reccomended, angle grinder discs home made these are custom to the size needed and won't shatter or fail on use.
Then at the far side the easy speed click things they cost 15 quid vs the 6 for angle grinder discs that I'm able to make 8 of from one disc for alot less. the speed clicks that are around 6 quids for 5.
Plus the custom ones can be made to any size that I can cut with diamond circular cutting hole saw on drill.
This might be useful if you need a cutting device that is of the smaller size.
I probably won't even use or open the dremel ones.
The home made ones will work very well and only down side is a few are slightly off round but can be ground down to make them better shape.
The dremel ones might come in handy when items visible or that are not getting perminently removed are worked on.


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I use these adaptors for my flexi windi driver when I cannot get in to tight places with the angle grinder with a cutting disc, they also fit well into a portable router motor and chuck also a fast electric drill. but be careful as there is no safety guard to protect you.dremmels have not got the strength for most work on the car.:)
Have been cutting into the nut it's nearly all the way through but now the rotary tool isn't spinning up properly.
Probably burned out the bushings or something.
I think it's almost down to the washer part.
Its not a real dremel so not that bothered about it.
The tensioner part was easy to break loose apart from its awkward to get at.
I will revert to cutting with the drill tomorrow as it takes ages.
The nut on the new part says 10 and adjuster is 8.8.

Was going to get compressor but decided it was not something I have space for as they are quite large.
The gearing is slipping when pressure is applied on rotary tool.
Just need to keep trying really thought it would be easy belt replacement 🤣
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Yes that would be ideal and I'm familiar with that brand from routers for woodworking.
I can at least say for now the idler pulley is of great quality.
Metal construction not plastic.
Came from auto doc have not had parts from them before.

The rotary tool I have atm looks like the mini katsu.
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Yes that would be ideal and I'm familiar with that brand from routers for woodworking.
I can at least say for now the idler pulley is of great quality.
Metal construction not plastic.
Came from auto doc have not had parts from them before.

Will have a look at the tool.
The trouble with the air compressors also is they have tiny motors on the ones I was looking at.
I passed on them after reading that they do not have the power for spraying etc.
Took all the discs to cut through then it took another couple hours to complete the job.
The bearing was fine and the belt seemed in pretty good condition.
I've left the short belt for now for another day.
Glad to be finished and working again.
This is what was left when I finished cutting it up with the drill.

If I could see the thing better it was cutting through the bolt and that is one tough bit o metal.
The bearing spins as well as the new one. 🤣
The new one was slightly wider tho only visual difference not painted and slightly wider.
I had to re use the back washer as that's not included the front cover washer is toasted as you can see.
Definitely need to invest in something with more cutting power in the future.
After the work completed I gave the belt a final tightening up to what seem as close to the previous belt.
I will check its tension in a week or so and it did run surprisingly quiet and smooth.
The cause is the wheel arch is rusty this is where the engine mount has been welded not sure how bad it actually is but it does not look good.
I can only say its beyond me to repair the inner wheel arch ? but the rest is probably okay if seen to soon.
Should take a picture of it. I think it's rotted but didn't touch it yet as first thought is to wire wheel the area.
To see if it's worth saving.
By inner wheel arch I mean directly below the headlight in the wheel arch.
Not the wing.
Have not yet inspected below the headlight and maybe that would be a good idea. It's not see through tho atm.


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