Technical 2005 multijet tensioner issue

[Dee H]

Hi all :wave:

Newly registerd on this wonderful forum.

I've driven Fiats for about 10 years now and I love them. I lost my fanatastic Grande Punto 1.3 multijet in an accident recently (hit an animal crossing the road at night) so I bought a 2005 Stilo multijet as its replacement. It has the 120 bhp 192.A8000 engine. No service history so I'm changing the timing belt. I bought the complete Gates kit (waterpump, tensioner, idler puley) and I got a new camshaft oil seal as well just in case. The install and timing setup all went fine but I'm having trouble with the tensioner. The indicator won't come up to the hole when I leverage the tensioner bracket towards the belt. And if I leverage the tensioner bracket and push the pointer up to the hole simultaneously (as I've seen some do) then it just drops back down after I tighten down the tensioner nut.

I eventually got the indicator to stay about halfway up to the hole and that was only after tightening the nut down rediculously hard - a lot more than the required 25nm. The nut looks original but it's quite rusty; there is a hole in the timing cover right where the tensioner is. (Does anyone know why? Makes no sense to me. Perhaps there's an additional cover missing?)

The car runs fine but I'm very uneasy about leaving the tensioner like this. Any idea what I'm doing wrong?

Any help is greatly appreciated!

 

[Ralf S.]

I can't clearly remember how it works... but I recall that if you just press on the pulley, the pointer will move but it is not being tensioned, so it will return to the slack position, as you noticed.

To get the pulley pointer to move and stay where it's tensioned to, you have to push the entire back-plate towards the oil-pump (i.e. "camshaft") pulley. The tensioner back plate has a fork in it that fits round a pimple on the engine casing so make sure that this fork doesn't jump the pimple while you do it (since the plate has to be slightly loose for you to move it).

When you tighten the nut, the tensioner pointer should then stay where it is... but turn the engine over a few times and then start it for a few seconds to see that the pointer is settled at the proper tension.


Ralf S.

 

[roll]

[ame]https://youtu.be/_NA5nXbQ76U?t=1175[/ame]
Try this

 

[Dee H]

I can't clearly remember how it works... but I recall that if you just press on the pulley, the pointer will move but it is not being tensioned, so it will return to the slack position, as you noticed.

To get the pulley pointer to move and stay where it's tensioned to, you have to push the entire back-plate towards the oil-pump (i.e. "camshaft") pulley. The tensioner back plate has a fork in it that fits round a pimple on the engine casing so make sure that this fork doesn't jump the pimple while you do it (since the plate has to be slightly loose for you to move it).

When you tighten the nut, the tensioner pointer should then stay where it is... but turn the engine over a few times and then start it for a few seconds to see that the pointer is settled at the proper tension.

Ralf S.

Thanks very much for posting Ralf. What you've described about locating the back-plate correctly, leaving the nut loose enough to slide it on the peg and pushing the tensioner back-plate / bracket and not the sprocket itself is indeed what I've done. And the pointer should then come up like you said. It's also clear in the vid that roll posted. I'm just stumped as to why mine doesn't do that. Right now I'm suspecting it's either the new tensioner from Gates (doubtful) or the old rusty nut (also a little doubtful, but less so).


I bought a new nut from a local Fiat garage and I'm going to try again this weekend. The mechanic said the same thing about the tensioner as everyone else: lever the back-plate toward the belt, pointer comes up, tighten the nut. Easy peasy. :doh:

Try this

Thanks for posting Roll. That is one of the vids I watched as I was researching this job. It's perfectly clear how it's supposed to be done and how the tensioner is supposed to behave. Mine just doesn't.

 

[Dee H]

Problem solved!


This time I leveraged the tensioner from the right side (front of the car) instead of from the left which is what I've seen people do in every youtube video that I watched on 1.9 JTD timing belts (Zafira, Alfa 159, and Croma). But that's a very awkward angle to leverage from on the Stilo. In my opinion it works a lot better from the opposite side. Tension is perfect now.

I also discarded the rusty old tensioner nut and fitted the new nylon lock nut. Feels a lot more secure.


Thanks very much for the feedback.

 

[Davren]

Not sure that I would be happy with a nylon lock nut on a hot engine part. Possibly why Fiat used an all metal lock nut.
.

 

[Dee H]

Not sure that I would be happy with a nylon lock nut on a hot engine part. Possibly why Fiat used an all metal lock nut.
.

That's a good point I suppose. My local Fiat dealer said the original all metal lock nut could not be ordered. He gave me the nylon one instead. You think I should put the original nut back on?


Do you know why the lower timing belt cover has an opening in it right where the tensioner nut is? Being exposed like that sure doesn't do that nut any good.

 

[Davren]

That's a good point I suppose. My local Fiat dealer said the original all metal lock nut could not be ordered. He gave me the nylon one instead. You think I should put the original nut back on?

I would be happier with a used metal locking nut than a new nylon one.

Do you know why the lower timing belt cover has an opening in it right where the tensioner nut is? Being exposed like that sure doesn't do that nut any good.

Perhaps one of the earlier deisel engines didn't have the automatic adjuster, but was adjustable through the hole. Once the the automatic one was designed, Fiat decided to use the same plastic cover. Just my guess.
.

 

[Ralf S.]

I think it's just so the cover fits over the threaded rod and/or it might be for inspection.


Ralf S.