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Alfa Romeo 145 - 146 Forum _ FAQ _ Variator: The Innards

Posted by: F355 13th April 2006 14:43

I finally got around to dismantling the Variator today. See pics below:


Click for bigger

Its quite a simple thing when you examine it but I still can't see what causes it to rattle.

Posted by: CMA 13th April 2006 15:27

Nice pics.

I think its because the timing is out the engine rattles not the variator that rattles, the oil seal and spring start to fail causing the inlet cam not to change the inlet timing.

"I think" so I'm expecting to be corrected....

Posted by: F355 13th April 2006 16:01

QUOTE(CMA @ Apr 13 2006, 03:27 PM)
Nice pics.

I think its because the timing is out the engine rattles not the variator that rattles, the oil seal and spring start to fail causing the inlet cam not to change the inlet timing.

"I think" so I'm expecting to be corrected....
*


No its definatly the variator that rattles. I think its caused by the splined shaft wearing, and the rattle is caused by the clearance between the shaft and the 'gear'.

Posted by: symonh2000 13th April 2006 16:53

The variator works by hydraulic pressure from oil contanied in it. The oil seal wears allowing the oil to drain, and all of the parts of the variator slop about. Hence the Ratle until it fills up with oil again. Also if the seal is worn it may not hold enough pressure to move the cam timing even when running as the oil can seep past the seals.
I think the Gear with the internal teeth moves along inside the inner shaft, and because of the spiral on the outer, it forces it to turn, taking the cam with it.

Posted by: GialloEvo94 13th April 2006 19:28

QUOTE(F355 @ Apr 13 2006, 03:43 PM)
I finally got around to dismantling the Variator today.
*

Nice one biggrin.gif

I was going to take my old one apart to see what was inside but you saved me a job smile.gif Do you have a pic of the inside of the casing? I guess there are just some teeth that the main gear fits into unsure.gif

Posted by: F355 13th April 2006 21:12

QUOTE(GialloEvo94 @ Apr 13 2006, 07:28 PM)
Nice one biggrin.gif

I was going to take my old one apart to see what was inside but you saved me a job smile.gif Do you have a pic of the inside of the casing? I guess there are just some teeth that the main gear fits into unsure.gif
*


I will take a picture tomorrow. It has helical cut splines inside. The helical cut gear then slides in (its a tight fit took me ages to get it out) then the spring and then the splined shaft.

Its a really simple intresting design... but like most Italian designs it never quite got perfected sad.gif

edit: the gear is the wrong way around in the bottom pic, whoops biggrin.gif

Posted by: alfista146 13th April 2006 22:38

Great pics,
When I did mine the local alfa garage wanted my old one(for overhaul) can it be that they just change the oil seal or is there a mod one can make to improve the design and lifespan of the things?
just curious
Alfista 146.gif

Posted by: crit71 14th April 2006 19:33

I know that you can get a repair kit for them, which consists of a new spring and seals IIRC..

Posted by: GialloEvo94 14th April 2006 23:43

Not content with seeing Ian's in pieces, I also took my old one apart today too rolleyes.gif It's a bit different in design though (I guess probably a later one) and they seem to have got rid of the rubber oil seal and put in a 'piston ring' type setup on the moving gear collar. I don't know what the idea of the groove in the splined shaft is for or the seperate split gear ring on the end unsure.gif Anyway, all these changes and it still didn't stop them from rattling laugh.gif

Click for bigger pictures...




Posted by: paulcanning69 15th April 2006 10:12

the rattle can come from the metal bearing round the variator that fits into the head, the little hole gets bigger

Posted by: GialloEvo94 15th April 2006 11:04

QUOTE(paulcanning69 @ Apr 15 2006, 11:12 AM)
the rattle can come from the metal bearing round the variator that fits into the head, the little hole gets bigger
*

If that's the case then why does the whole variator need to be changed to get rid of the rattle? huh.gif There was no real visible wear on the casing of the variator or on the shell bearings in my head.

IIRC Ian didn't replace the shells on his, just the variator unsure.gif

Posted by: F355 15th April 2006 11:12

QUOTE(GialloEvo94 @ Apr 14 2006, 11:43 PM)
Not content with seeing Ian's in pieces, I also took my old one apart today too rolleyes.gif It's a bit different in design though (I guess probably a later one) and they seem to have got rid of the rubber oil seal and put in a 'piston ring' type setup on the moving gear collar. I don't know what the idea of the groove in the splined shaft is for or the seperate split gear ring on the end unsure.gif Anyway, all these changes and it still didn't stop them from rattling laugh.gif

Click for bigger pictures...
<snip>
*


Thats intresting... they seem to have made it more complicated.

Was yours constantly rattling or just on startup?

Posted by: F355 15th April 2006 11:19

QUOTE(GialloEvo94 @ Apr 15 2006, 11:04 AM)
QUOTE(paulcanning69 @ Apr 15 2006, 11:12 AM)
the rattle can come from the metal bearing round the variator that fits into the head, the little hole gets bigger
*

If that's the case then why does the whole variator need to be changed to get rid of the rattle? huh.gif There was no real visible wear on the casing of the variator or on the shell bearings in my head.

IIRC Ian didn't replace the shells on his, just the variator unsure.gif
*



Same with me. If its the shell bearings I will eat my variator with tomato ketchup tongue.gif

Posted by: paulcanning69 15th April 2006 11:19

well try and replace the shell bearings that could be the problem me thinks

Posted by: F355 15th April 2006 11:21

QUOTE(paulcanning69 @ Apr 15 2006, 11:19 AM)
well try and replace the shell bearings that could be the problem me thinks
*


It isn't, trust me!

Posted by: GialloEvo94 15th April 2006 12:34

QUOTE(F355 @ Apr 15 2006, 12:12 PM)
Was yours constantly rattling or just on startup?
*

Mine just rattled for about 30 seconds after starting the engine and was much worse with a cold engine. Once past the 30 second period I never heard any more rattling until I next started the engine.

Posted by: GTA 17th January 2008 10:44

What is the worst that can happen with a worn variator?

Posted by: GialloEvo94 17th January 2008 11:53

QUOTE(GTA @ 17th January 2008 10:44) *
What is the worst that can happen with a worn variator?

Usually just noisy at startup and possible slight lack of performance.

However, AforAlfa (another member on here) did previously mention that he'd seen a variator before with completely stripped gear teeth inside meaning that it just spins round inside without transferring the inlet cam wheel drive to the inlet camshaft which would result in a damaged top end (trashed inlet valves). I really can't believe this situation to be anything other than very very rare though (and very very unlucky) because to completely strip the hardened teeth inside the variator would take a serious amount of torque through the cam wheel with the camshaft probably also jammed in some way meaning that the top end would already be a gonner anyway.

With a worn variator then in 99.9% of cases, the engine will continue to run without any resulting damage for many more tens of thousands of miles/kilometres.

Posted by: AforAlfa 18th January 2008 14:58

another worn variator story, speaking to a fiat coupe specialist, he had a running fault that he could just not find, this 20vt was as rough as feck apparently, and when checking valve timing, he took the belt off, and the variator could be rocked by hand, moving a fair old way from rest, but they dont make a noise on coops, dont ask me why, exactly the same part, with the same thing i find wrong with them, but no noise, he has since cured many running probs with coops by replacing variators.

Posted by: Ransoman 19th January 2008 00:31

I didn't think the 20v turbos had variators? I believe the newer "vis" NA 20v has one though but i thought it was a different design??

Posted by: alfats 24th July 2008 18:29

QUOTE(crit71 @ 14th April 2006 19:33) *
I know that you can get a repair kit for them, which consists of a new spring and seals IIRC..



bit out of time do u know where i can get repairt kit for it ?

Posted by: GialloEvo94 25th July 2008 08:40

QUOTE(alfats @ 24th July 2008 19:29) *
bit out of time do u know where i can get repairt kit for it ?

I'm not aware of any repair kits available. They certainly aren't listed in the parts catalogue. Anyway, it's the internal gear teeth that actually wear and these aren't repairable as they are part of the variator body itself. The only thing you could possibly repair is an oil leak by replacing the internal 'o' ring. If the variator is rattling then unfortunately the only cure is to replace your current one with a complete new unit.

Posted by: JeremyG 5th January 2019 18:00

I've read elsewhere about variator repair kits - comprising a fresh spring and plastic o-ring.

I had to order some parts for the 166 yesterday and saw, on the Alfa Workshop website, an article on stripping the variator and fitting the kit:

https://www.alfaworkshop.co.uk/alfa_fitting_twin_spark_Variator_relief_kit.shtml

At 9.00 the kit is way cheaper than replacing the whole variator - so I bought one:



As I've already got a new variator for the 145 I'll fit it first then try fitting the repair kit to the old variator... and keep it behind my ear for later...

Has anyone tried this?

Posted by: Ganz 5th January 2019 23:37

Not tried it but I've heard from someone who has installed a few that they're not very good and don't last very long. He said that perhaps one worked on a motor. Was thinking of doing it myself but thought might as well buy a replacement if I'm taking the camshaft off and then timing the belts. Good luck with it though. Hope it works.

Posted by: dante giacosa 6th January 2019 22:23

QUOTE(Ganz @ 5th January 2019 23:37) *
Not tried it but I've heard from someone who has installed a few that they're not very good and don't last very long. He said that perhaps one worked on a motor. Was thinking of doing it myself but thought might as well buy a replacement if I'm taking the camshaft off and then timing the belts. Good luck with it though. Hope it works.


Yeah- I hope it works too- that's amazing: I had never read of a fix for it...

'Could' be sensational, but as Ganz says...

P.S.- you win this years' thread-resurrection prize hands down, Jeremy!! July 2008 > January 2019 !!!

Posted by: JeremyG 7th January 2019 13:57

QUOTE(dante giacosa @ 6th January 2019 22:23) *
P.S.- you win this years' thread-resurrection prize hands down, Jeremy!! July 2008 > January 2019 !!!


Haha! No point re-inventing the wheel, eh?

Posted by: JeremyG 12th January 2019 17:15

QUOTE(JeremyG @ 7th January 2019 13:57) *
Haha! No point re-inventing the wheel, eh?


Having dismantled my old variator, it looks like I have the old type (as per the first post in this thread) - whilst the repair kit is for the later type (as per GialloEvo's post).

If anyone wants the repair kit, let me know!

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