Alfa Pages

16v campervan · Posted: Tue Apr 24, 2007 9:57 pm Post subject: Cam belt tensioner bearings.

Managed to get the engine running now by powering up the fuel pump independently as I think it has a duff relay. Sounds pretty good and runs reasonably well, though I haven't driven it yet as I've decided to change the belts and renew the tensioner and idler bearings. I've popped the belts on and off a couple of times and Its pretty straight forward using a ratchet spanner to hold the inlet cam pulley in place under tension. I do this using the altenator belt (disconnected from crank pulley) to hold the spanner in place and it takes about 5-10 mins to do one belt.
Whats puzzling me is that having removed the tensioner and idlers the bearings seem a little sloppy. However I bought new SKF bearings (£5 each) and these also have, to my mind, a fair bit of movement in them! Also the plastic wheels have a lip on each side of the bearing which was damaged when I pushed the bearing out and I don't think you can push the new bearing in without removing a large amount of the lip. any suggestions?

tvatavuk · Posted: Tue Apr 24, 2007 11:04 pm Post subject:

When I bought SKF bearings they had plastic wheel bit on them so I guess bearing was never ment to be replaced as part only complete bearing+plastic wheel thing. Usual price in Croatia from 8-10£ each.
_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

Scott Sander · Posted: Mon Jun 04, 2007 1:29 am Post subject:

tvatavuk · Posted: Mon Jun 04, 2007 8:08 am Post subject:

Sorry I don't remember.
Looking at website- good link Smile

Part no u provided is for whole kit 4 bearings + 2 belts.
Only bearing in plastic housing could be VKM 22510.
_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

Scott Sander · Posted: Mon Jun 04, 2007 12:08 pm Post subject:

Tino,

Yeah thought it was a bit strange that they would be providing the belts, but if I’m going to do the tensioners the belts will also get replaced. I assume they would use a good quality belt. So I might go with the whole kit.
_________________
Scott Sander
'91 Alfa 33 Boxer 16V Monza - Awesome
http://www.sanderfamily.com

gritsop · Posted: Mon Jun 04, 2007 2:40 pm Post subject:

Hi,

Think I need to share my experience with SKF tensioners. Just a few days ago I got a set of SKF tensioners for my 1.4 IE (part no. VKM 12500, 12501) and upon reaching the garage and having removed old belts, tensioners, the mechanic notifies me that one of the two tensioners cannot be installed due to an excess amount of metal shavings inside the bore of the tensioner. The spring that actually locks the tensioner to the engine block could not pass through the opening on the rear of the tensioner... Crying or Very sad

In addition on the other side of the metal shavings showed by the arrow (180 degrees opposite side) there was also another pile of metal shaving which wasn't difficult to break and free the space Rolling Eyes

The amount of the shavings is big enough and no matter how much trying to get rid of it with a hammer and a chisel I didn't get away with a replacement tensioner. So now one side of the engine has an SKF tensioner whereas the other side an Italian one of unknown brand Evil or Very Mad

See the photo

So guys be careful when buying these things as one quality problem of the production line can lead you to unpleasant surprises.

Regards
_________________
Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive

http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop

tvatavuk · Posted: Tue Jun 05, 2007 10:25 am Post subject:

Scott, at this point I don't trust enyone not even belt makers that their belts are ok Smile

Gristop, ty for that input and nice picture.
On 16v you just change bearing with plasitc shell , it doesn't come with metal arm (picutred above) nor spring. You pop out old plastic shelled bearing and pop in new one.
I find this better choice beacuase you don't have to buy expencive things you don't need. ie that metal arm needs replacing only if damaged in crash. ie Here for price of 16v bearing with arm is same as 2 bearings.
SKF like any other brand have better and worse products or batches and also have fakes. I just find them better quality then rest for that money.
_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

Bellamachinna · Posted: Tue Jun 05, 2007 2:37 pm Post subject:

On my worst experience, the bearings that came with the DAYCO belts, are crap...

They seized completly, on the 2 tensioners, and on one of the rollers...
Resulted in the left hand belt snaping.

Fortunatly, the belt, when snaped, rolled itself against the camshaft pulleys, and locked them in place, WITH ALL VALVES CLOSED Cool

....

Result:
As i had to remove the head, to insure that there was no valve to piston contact, the engine was fully stripped...
Now, its being rebuilted, and i`m installing new piston rings, new rod bearings, new crank bearings and new seals...
And obviously, new belts... (not DAYCO, this time).

All the best
P.Camilo
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All'interno della mia macchina, vi sedete, tenete sopra e CHIUDETE IN SU...

tvatavuk · Posted: Wed Jun 06, 2007 12:53 am Post subject:

In about 100k km I changed 5 times timing belts on my P4.
In case u migh ask yourself why here is rough list:
1. 1998 110k km only Pirelli belts - when I bought car
2. 1998 125k km Pirelli belts + SKF bearings and SKF water pump - when water pump leaked, showing that one of bearings is not so in tip top shape as mechanic though 20k km before and belts were around 5-10cm longer then when installed
3 2003 170k km DAyco Belts/SKF bearings - just for fun 5 y from last change
4. 2006 190k km - DAYCO belts, SKF bearings and DELPHI water pump- Engine small rebuilt (gaskets , bearings and piston rings) - (everything was ok but didnt wanna repeat 125k km scenario)
5. 2006 200k km- Gates belts and SKF bearings - oil leak from camshaft front oil seal no so long ago newly replaced.

on 2nd and 5th belts were soo lose/ streched/damaged that it must be Gods intervention that they haven't fallen off.
_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

ZeNiTh-PbArM · Posted: Thu Jun 07, 2007 6:43 pm Post subject:

Hi,

I also notice that the belts we get today are crap. I changed dozens of belts on my 8v 33 and others, always tensioning the belts according to spec : engine at TDC, rotate crank 90° clockwise, perform tensioning on driver side (LHD) then rotate 360° and repeat passenger side. Bolts torqued down to 4.7mkg as usual.
Well for the past to years all the belts i've installed that way whine after installation, i have to lower tension on bearings for the whine to go away. Belts can then be twisted a little more than 90° between fingers if tension of the belts is slack enough not to get the whine! This is due to belts, no matter what brand they are ( i use to buy mine at the local Alfa dealer but have also tried other makes).
Anyone experienced this?

Regards,
zp

ps : skf tensioners are the best in my opinion, the bearings don't fail too early and as pictured below you have an inner tube to hold the tensioner on its axle, which some of the other makes (including some of the Alfa units!) don't feature