help - aux belt tension

[rd070707]

I changed my crank pulley today for a solid replacement and got it all changed okay and new belt on etc but now the belts to loose slightly and it flutters at idle. looking down on the top tensioner, it moves back and forward a bit...

can someone explain to me how the tensioning works or is my tensioner just shot?

cheers

[Poodle]

Definitely get the right length belt? Also, theres a manual tensioner to adjust below the auto-tensioner.

That said, if your auto-tensioner is wobbling its probably shot, loosen off the belt again and check the tensioner by hand, if theres play or graunchy bearings then sack it off for a new one.

[rd070707]

okay cheers mate. see it didnt do that with the old belt and i would be surprised if we done anything to break it, but yeah the manual tensioner, i slackened it off first because i thought it was the one to use, then i slacked the bolt on the auto tensioner and my mate slipped the belt off and we did the reverse for refitting. i think this manual one needs adjusting but im not sure how.

the belt was the right length for aircon yes and matched the old one

[Toms306]

I think the auto-tensioner should move a bit!? I've got a brand new one that moves at idle, the old one didnt move back and forth at all...it just pushed the belt off lol, I assumed it was to damp the engine vibrations so the pumps get a smoother 'pull' but I could be wrong...

[rd070707]

yeah see the problem is the slack though, at idle you can see the looseness between the crank and air con. i think its something to do with the second, eccentric tensioner but im not sure how to set that up right to increase tension

[Toms306]

Im sure you just put an allen key in and turn it towards to belt? I've never touched the manual though so could be wrong!

[rd070707]

il have another poke tomorrow, its not that bad but it is loose. just getting my head around what way to turn it to tighten, either that or my auto tensioner has had it

[Toms306]

It cant be hard, you'll see if it tightens or loosens lol.

I wouldn' think your auto's knackered, as said mines brand new and moves. Well it did when I first fitted it...may have settled now I guess, haven't looked!

[rd070707]

it doesnt seem visually loose though its only slight, but yes im sure il get it sorted tomorrows a new day lol. glad to have my new bottom pulley on though its a lot smoother

[Oil-burner]

Yeah the manual tensioner is on a cam, turn the Allen key and it will tighten.
There's 3 marks on your auto tensioner that indicate belt wear but you'll have to see Haynes to find which one it should be on.

[rd070707]

thanks mate, i tried loosening the allen key bolt, then tightening the square one, and then tightening up the allen key bolt again earlier but each time i started the car it was still flapping slightly

[Oil-burner]

I can't 100% remember how it goes tbh, been a while since I did one I know it was fiddley as f*ck to tension it tho.
You'll see when it has gone to its full extension, as I said there is a wear indicator on the auto adjuster so you'll see if its tight enough.
Iirc I got someone else to take the strain of the auto tensioner while I set the manual one in place, makes things a bit easier.

[rd070707]

right right i see now if someone slackened the auto one while i was doing it. and i know the lines you are talking about, il try look up find out which ones should line up

[Oil-burner]

Iirc it's the furthest line away from you as you look from the front of the car.

[Poodle]

Slacken the auto tensioner, you can use a couple of big cable ties to hold the spanner back if you're doing it by yourself or get a small allen key in the slot to lock it out. Then undo the allen bolt on the manual tensioner, rotate it on the cam so it's taking up all the slack on the aux belt. Retighten the allen bolt while holding the manual tensioner in place, then release the auto-tensioner. Job done.

[rd070707]

spot on mate will do it in the morning, we were trying to adjust the manual one with the auto one released. cheers

[Poodle]

No worries, glad to help.

[rd070707]

tried it this morning, slackened the top auto tensioner and set the manual one its its tightest position, ie furthest away from the direction the belt is coming from, then i released the top one but no change. think the auto tensioner is shot

[Poodle]

Just whip the belt off amd check all your pulleys by hand, can soon tell which is the culprit.

[rd070707]

Yeah they all moved free when I had it off yesterday, I'd say this top tensioner isn't holding the tension. Because I had the bottom one set up so the square side of the eccentic pulley was to the bottom which I assume is the tightest it goes

[Poodle]

Try it and see i guess, seems a good bet from what you've said.

[rd070707]

if i had a diagram it would be easier to explain but basically the eccentric one cant take anymore slack so it must be the top ones spring

[Poodle]

What you're saying makes sense, just seems odd the problem should show up now you've fitted a new bottom pulley. Are you sure it's not just where the new solid pulley doesn't have any damping?

[rd070707]

all seems fine with the pulley, just really noticeable flapping between it and the aircon pulley at idle, and the top tensioner seems to hop slightly looking from above

[Toms306]

I checked mine again yesterday - the autotensioner does still move a bit at idle. The belt doesn't flap at all though.

[rd070707]

got this sorted today, replaced the auto tensioner and all is good and tight now

[Jonny81191]

Hope this isn't the issue with mine, it's not running straight on the power steering pump, and therefore squealing like a pig. it was fine before I bought a new (gates) kit.

[Toms306]

Did you change the auto tensuoner jonny? I'm sure mine only broke cos I replaced the six belt! Even with new belt and tensioner mine still squeals on a cold start though, think it gets damp over night.

[rd070707]

mine just wasnt holding tension, and squeeled when cold as the belt was in poor knick

[Toms306]

Mine kept pushing the belt off centre (away from the engine) and not square on the pas pump lol.... Plus the tensioner bearings were noisy.