Pulley bearing?

[Samblers]

Anyone care to watch this 10s video and confirm my suspicions of a pulley bearing problem? Comes across as an intermittent *tick* sound in the video... its more pronounced in real life.

IMG 2410 - YouTube (https://youtu.be/H-W5mzcaORY)

Done some water crossings recently. Sounds to me like a catching, dry bearing?

Theres a few pulleys and bearings down there, any way of finding out which is the culprit?

Cheers, Sam
(2010 2.4 Puma)

[Robmacca]

I'm not real sure but that doesn't sound like it a bearing problem

[Xtreme]

I'm can't tell from the video either but once you've got the fan and belt off it's not too hard to check all of the idler pulleys.
I've even prised the little plastic bits off each side of the bearings, washed them out, regreased them and refitted. Still going OK 45k kms later.
Probably worth doing just to eliminate one possibility.

[Samblers]

Ok thanks, I might do that. The noise is definitely coming from some belt (or fan?) related component…

Years ago I had an intermittently binding CV joint that sounded very similar

[carpdvl]

Ok thanks, I might do that. The noise is definitely coming from some belt (or fan?) related component…

Years ago I had an intermittently binding CV joint that sounded very similarCan't be of much help diagnosing but doesn't sound like a bearing - my tensioner pulley bearing disintegrated a couple of months ago and that sounds more akin to a burst intake hose (a whooshing sound almost). My belt had also moved across and was rubbing the block due to the broken bearing

You'd be hearing it more frequently than an odd knock given those bearings spin at such high RPMs

Can you see what the tensioners doing? Maybe pull the cowling off, the AC cover etc and run it. As above mentioned just detension the belt and have a spin of all the pulleys. Hold a long screwdriver to your ear and touch it on the different components (AC compressor, diff pulleys) carefully and might be able to zero in on the noise

[Samblers]

Thanks, input appreciated. I'll have a go at that and report back.

Cheers, Sam

[carpdvl]

Thanks, input appreciated. I'll have a go at that and report back.

Cheers, Sam

Just had another listen... it almost sounds like something could be clipping the viscous fan under the cowling?... Like something flicking into it periodically as the wind picks it up although buckley's as to what that could be... Just an idea which will be quickly and easily identified by just undoing those six screw clips and pulling the cowling off if so

[roverrescue]

It’s not the silly turbo heat shield at all is it ?
Loose nut / broken mount allowing intermittent tapping against the mounts ?


I agree with above that it doesn’t sound like a pulley
But if your game the quickest way to check the pulleys is to slip the belt off on a cold engine and turn it over … won’t kill the engine with the water pump not turning for 10 seconds


Steve

[Samblers]

Thanks both, great suggestions, I’ll get onto it this weekend

Cheers, Sam

[FisherX]

I had that kind of noise in our FL2. Does the noise go away when it heats up?

It ended up being the alternator pulley clutch in my instance. (I'm not sure if a Defender has the clutch).

[Samblers]

I’ve taken the cowl off and had a listen. It’s coming from the left side of the engine as I look at it (so the tensioner/ alternator side). The fan isn’t touching anything.

I’m think i’ll need to run the engine with no fan on, is this OK?

Can I run the engine with no belt (for a very short period), or just turn it over by hand?

Cheers, Sam

[Samblers]

It’s a tapping noise… though it could almost be a sparking type noise too, given alternator is involved.

[POD]

I’ve taken the cowl off and had a listen. It’s coming from the left side of the engine as I look at it (so the tensioner/ alternator side). The fan isn’t touching anything.

I’m think i’ll need to run the engine with no fan on, is this OK?

Can I run the engine with no belt (for a very short period), or just turn it over by hand?

Cheers, Sam

You won't do any harm running without the belt for the 30 seconds or so that it will take to determine if the noise goes away. Especially if you do it with the engine cold (assuming the noise is present when cold?).

[Samblers]

Yep i'll do that. Noise is there from cold, yes.

Difficult to say wether it disappears when driving, obviously the engine noise drowns out all else

[Samblers]

Took my fan off and ran it... looks like my tensioner is jumping around.

Slo-mo vid here (had to slow it down to capture):

IMG 2467 - YouTube (https://youtu.be/zPFrZnM6eJw)

The pulley above it (idler of some kind) has a bearing that is a little loose, so I guess i'll replace both these components

[Samblers]

Done a little bit of reading on this now and sense I might be disappearing down a worm hole...

- should the belt tensioner being jumping up and down at idle like this? some say yes, some say no (I'm saying no)

- what would make it jump up and down like this? presume some cyclical tension on/off or low/high in the belt... but from what?

- some say to check harmonic balancer... how? it spins fine... in fact all pulleys feel like they are spinning ok, with no rough bearings

Cheers, Sam

[carpdvl]

Done a little bit of reading on this now and sense I might be disappearing down a worm hole...

- should the belt tensioner being jumping up and down at idle like this? some say yes, some say no (I'm saying no)

- what would make it jump up and down like this? presume some cyclical tension on/off or low/high in the belt... but from what?

- some say to check harmonic balancer... how? it spins fine... in fact all pulleys feel like they are spinning ok, with no rough bearings

Cheers, SamMine jumps like that still (far worse when the bearing in it had gone) but I don't think it's a major issue. May also be cyclical loading/unloading of the engine itself ticking over not 100% sure.

Either way don't think that is what is going to hurt it.

Take the belt off, run it cold. If you get no ticking you know it's related to one of the accessories and can start running through those.

Do the pulleys on the alternator and AC compressor wiggle at all etc.

Turbo heatshield above was also a good suggestion, though when mine cracked it made a rattling noise pretty consistently so I just got rid of it.

[Samblers]

Mine jumps like that still

Hmm.

Run with the belt off there's no noise. None of the accessory pulleys have grumbling bearings, though have a little end-play. Don't know if thats normal.

To be honest, the tapping/ clacking sound i'm hearing could well be a pulley in/out/endplay sort of a sound... if something were causing the belt to flap/move.

I guess tensioner is the first thing I'll change out, to rule it out.

[DiscoMick]

On our D1 back a few years there was a ticking sound which turned out to be a faulty pulley affecting a belt. Replacing the pulley stopped the ticking.

[POD]

I think your noise sounded more like something coming loose than a bad bearing. Have you checked all the bolts on things like the alternator, a/c compressor etc?
What does the belt look like?
BTW, you can replace the bearing in the belt tensioner, it has to be done carefully to not warp the pressed-metal pulley. Replacing the fan bearing is a pain of a job, the big plate across the front of the engine has to be removed. LR don't offer the bearing as a separate part- they want to sell you the whole front casting, around $700 several years ago when I did mine. The dual-row roller bearing is about $50

I wasn't aware these engines had a harmonic balancer; if that is the case, does the bottom pulley run true when you idle the engine?

[Samblers]

Yeah I was wrong about harmonic balancer, sorry about that (don’t believe everything you read)

Belt is new (8k km ago) and I can’t see anything loose. I’ve ordered a tensioner and a couple of pulleys and will report back when these have been fitted.

Really appreciate all the help thus far

[Samblers]

New tensioner and idler pulley made no difference, so scrub that.

The noise seems to be coming from the alternator, though cannot be felt if components are touched during running.

A longer video: IMG 2476 - YouTube (https://youtu.be/6ebaDMiLMGw)

I wonder if the alternator rotating components are hitting something inside (gravel?). It sounds a little like a sparking/ shorting noise but as you can see in the video I turned lights off and could see no sparks during running.

So take alternator out???

[carpdvl]

New tensioner and idler pulley made no difference, so scrub that.

The noise seems to be coming from the alternator, though cannot be felt if components are touched during running.

A longer video: IMG 2476 - YouTube (https://youtu.be/6ebaDMiLMGw)

I wonder if the alternator rotating components are hitting something inside (gravel?). It sounds a little like a sparking/ shorting noise but as you can see in the video I turned lights off and could see no sparks during running.

So take alternator out???

Sounds you are on the right track. You must be an expert at taking that belt on and off now!

I think that'd be my next port of call. Pull the alternator, check it for debris and check for play in the rotor - could be the rotor shaft bearing has **** the bed but would've thought it'd sound different. Or maybe some a rocks gotten in there and damaged the windings...

No way to tell till you get it out but given you've basically isolated it to the alternator it seems the ends in sight.

If anything an opportunity to give it a clean if you've taken it through any mud historically.

[Samblers]

Thanks, yeah that’s what I’ll do. Done some water crossings recently.

My Dads money is on a tight bearing in the alternator starting to bind … will report back

Cheers, Sam

[Samblers]

Pull the alternator, check it for debris and check for play in the rotor - could be the rotor shaft bearing has **** the bed but would've thought it'd sound different. Or maybe some a rocks gotten in there and damaged the windings...


I have the alternator on the bench. Nothing inside rattles or sounds loose.

The bearing at the front that holds the pulley on seems very dry though, its squeaks and clicks a little in the reverse direction, though doesn't bind.

Its a Bosch unit. Can these be disassembled for servicing? Can the front pulley bearing be changed out?

[carpdvl]

I have the alternator on the bench. Nothing inside rattles or sounds loose.

The bearing at the front that holds the pulley on seems very dry though, its squeaks and clicks a little in the reverse direction, though doesn't bind.

Its a Bosch unit. Can these be disassembled for servicing? Can the front pulley bearing be changed out?


Can't say I've disassembled mine but yeah they all should do.

That being said, just had a quick search and this sounds eerily familiar: DEFENDER2.NET - View topic - Puma Alternator Pulley. (https://www.defender2.net/forum/post652706.html)

Makes sense - its an overrunning alternator pulley which allows the alternator to decouple from the fan belt due to the variations in the belt. Google for more info. The free-wheel mechanism in yours may be stuffed.

There's links in that other thread and part numbers, but looks like need a puller and the bearing. Still should be cheaper than a new alternator.

[Samblers]

That being said, just had a quick search and this sounds eerily familiar: DEFENDER2.NET - View topic - Puma Alternator Pulley. (https://www.defender2.net/forum/post652706.html)


Amazing. Thanks so much.

[FisherX]

They are easy to change, but you need the tool kit to do the job.


Dayco Overrunning Alternator Pulley for Land Rover Defender 130 2.4L 244DT | eBay (https://www.ebay.com.au/itm/113699149480)

13Pcs Alternator Pulley Tool Kit Garage Automotive Freewheel Removal Socket Set | eBay (https://www.ebay.com.au/itm/373273077163?chn=ps&norover=1&mkevt=1&mkrid=705-139619-5960-0&mkcid=2&itemid=373273077163&targetid=1280421174239&device=c&mktype=pla&googleloc=1000652&poi=&campaignid=10101784988&mkgroupid=128008448292&rlsatarget=pla-1280421174239&abcId=9300367&merchantid=7364522&gclid=CjwKCAjwgISIBhBfEiwALE19ScT8yoQV_a9VmePVbLma 9BtJtPW1PKvRvWRNrBNRMLApVvxLGztQ3RoCrcgQAvD_BwE)

[Samblers]

Thanks, i'm onto it now and think this is my problem.

Really appreciate all the help [thumbsupbig]

[carpdvl]

Thanks, i'm onto it now and think this is my problem.

Really appreciate all the help [thumbsupbig]

Chuck some details and pics up of how you go / once it's fixed - the more info out there the better for us battlers!

[Samblers]

Will do. Always helpful when others do this and i'm searching for info years down the line :)

Picking up pulley and tools this morning

[Samblers]

Well, that seems to have fixed it.

The issue, as far as I can tell, is caused by the tensioner 'bounce' at idle, which is normal from what others have said, but causes the upstream pulley (the alternator one) cyclic under-rotation, i.e. repeated on/off engagement of the over-run mechanism, and which goes away when engine revved. Noise might appear to be caused by tensioner bouncing but is actually a fault in the alt. pulley overrun mechanism - mine was clicky in reverse.

Might've lasted a fair bit longer... but why risk it.

No pics (I was in too much of a rage trying to get the alternator back on anyway [bigwhistle]), but some tips for other novices like myself:

- you dont have to take the alternator off to remove the pulley (I wish I'd left mine on)
- you need the tool - M10 inner spline and 33T outer spline for Bosch alt. on my Puma.
- You hold the inner spline steady (its the alt. spindle), and undo the outer one... not the other way around, as I only found out from this video: 7052 | Alternator Pulley Tool Kit - YouTube (https://www.youtube.com/watch?v=dNsfMLf8xpg)
- its a regular right-handed thread; the one in the video above is reverse-threaded

I replaced the tensioner (un-necessary) and one of the idler pulleys (which i accidentally damaged) discovering the problem... a treat for the Defender.

Hope this helps,

Sam