Lancia Beta Forum
March 28, 2024, 11:04:35 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: NEC Restoration Show 22nd-24th March 2024
http://www.betaboyz.myzen.co.uk/forum/index.php?topic=5015.msg36852#msg36852
 
   Home   Help Contact Admin Search Calendar Gallery Articles Login Register  
Pages: [1]
  Print  
Author Topic: Cam belt tensioner bearing identification  (Read 2140 times)
0 Members and 1 Guest are viewing this topic.
Nigel
Hero Member
*****
Offline Offline

United Kingdom United Kingdom

Posts: 861



« on: January 26, 2020, 02:00:55 PM »

Hi all,
A very old thread on here identified this:

http://uk.rs-online.com/web/p/ball-bearings/2851692/

This cam belt tensioner bearing is listed as
25mm internal diameter
52mm external diameter
20.6mm width

Where as mine,just removed, is
24.9mm internal
51.83mm external
20.5mm width

Will this fit? Am I being pedantic? Are these normal tolerances?

Thanks in advance
Nigel

Logged

1984 2.0 Carb HPE [ex Aus] Grigio Finanza.
2007 Mazda 6 2.3 [current daily, highly recommended]
The past:
1980 2.0 HPE White in South Africa [hope it survives!]
1976 1.6 Coupe Lancia Blu [PFG 76R] [probably deceased]
oh,and an Uno Turbo 1997 also in SA [stolen,never recovered]
peteracs
Administrator
Legendary Member
******
Offline Offline

United Kingdom United Kingdom

Posts: 3822


Peter Stokes


« Reply #1 on: January 26, 2020, 02:18:54 PM »

Hi Nigel

So long as it fits on the the spindle ok, then the outer dimensions will be fine as the tensioner will adjust to the belt I think you will find the belt tolerances are somewhat larger....

Peter
Logged

Beta Spyder S2 pre F/L 1600
Beta HPE S2 pre F/L 1600
Nigel
Hero Member
*****
Offline Offline

United Kingdom United Kingdom

Posts: 861



« Reply #2 on: January 26, 2020, 02:32:53 PM »

Hi Nigel

So long as it fits on the the spindle ok, then the outer dimensions will be fine as the tensioner will adjust to the belt I think you will find the belt tolerances are somewhat larger....

Peter


Peter,
This is just the bearing,not the whole pulley. So its got to fit within the housing.

Nigel
Logged

1984 2.0 Carb HPE [ex Aus] Grigio Finanza.
2007 Mazda 6 2.3 [current daily, highly recommended]
The past:
1980 2.0 HPE White in South Africa [hope it survives!]
1976 1.6 Coupe Lancia Blu [PFG 76R] [probably deceased]
oh,and an Uno Turbo 1997 also in SA [stolen,never recovered]
peteracs
Administrator
Legendary Member
******
Offline Offline

United Kingdom United Kingdom

Posts: 3822


Peter Stokes


« Reply #3 on: January 26, 2020, 03:11:08 PM »

Hi Nigel

Sorry, I was thinking of the Saab one I recently replaced. Guess the only way to know is to try fitting it if that is practical. I noticed for the wheel bearings that there are two slightly different od sizes listed on specs of bearings I have for the rear ones I am replacing, the difference is 0.2mm, I guess it all depends what tolerance was originally designed in.

Peter
Logged

Beta Spyder S2 pre F/L 1600
Beta HPE S2 pre F/L 1600
rossocorsa
Legendary Member
******
Offline Offline

United Kingdom United Kingdom

Posts: 2373


« Reply #4 on: January 27, 2020, 12:44:12 AM »

I imagine they are the same, the reason I chose that particular bearing spec is partly lost in the random memory of my becoming senile mind but I think I recall it was too do with designed rotation speed and the fact that it has a plastic cage so will fail in a less catastrophic manner giving some kind of warning of failure prior to seizure, plus of course SKF are always very good.
Logged
mangocrazy
Legendary Member
******
Offline Offline

United Kingdom United Kingdom

Posts: 1347


Graham Stewart


« Reply #5 on: January 27, 2020, 10:27:35 AM »

Every bearing/retainer interface I've come across has been a snug push fit; i.e. no need to get the bearing pressed into the housing. It doesn't exactly 'drop in' but doesn't put up too much of a fight. It's a tight enough fit that pressure on the outer of the housing causes the bearing to spin, rather than the bearing to spin in the housing, if you know what I mean. This assumes that all parts are clean, rust free and lightly lubricated (not the outer part of the housing that contacts the belt, obviously) when assembled.

The only time I'd be concerned is if the bearing is a sloppy fit in the housing. If you buy the one-piece part of course this area of concern is obviated.
Logged

1980 Lancia Beta Spider 2000 (S2FL)
2002 VW Transporter T4
2017 KTM Duke 690R
2008 Aprilia SL1000 Falco
1992 Ducati 888 SP3
1988 Honda VFR750F
1980 Yamaha RD350LC
rossocorsa
Legendary Member
******
Offline Offline

United Kingdom United Kingdom

Posts: 2373


« Reply #6 on: January 27, 2020, 06:31:39 PM »

Every bearing/retainer interface I've come across has been a snug push fit; i.e. no need to get the bearing pressed into the housing. It doesn't exactly 'drop in' but doesn't put up too much of a fight. It's a tight enough fit that pressure on the outer of the housing causes the bearing to spin, rather than the bearing to spin in the housing, if you know what I mean. This assumes that all parts are clean, rust free and lightly lubricated (not the outer part of the housing that contacts the belt, obviously) when assembled.

The only time I'd be concerned is if the bearing is a sloppy fit in the housing. If you buy the one-piece part of course this area of concern is obviated.

Most single piece ones available now are the wrong size for 2 litre cars though
Logged
Nigel
Hero Member
*****
Offline Offline

United Kingdom United Kingdom

Posts: 861



« Reply #7 on: January 27, 2020, 07:39:59 PM »

Every bearing/retainer interface I've come across has been a snug push fit; i.e. no need to get the bearing pressed into the housing. It doesn't exactly 'drop in' but doesn't put up too much of a fight. It's a tight enough fit that pressure on the outer of the housing causes the bearing to spin, rather than the bearing to spin in the housing, if you know what I mean. This assumes that all parts are clean, rust free and lightly lubricated (not the outer part of the housing that contacts the belt, obviously) when assembled.

The only time I'd be concerned is if the bearing is a sloppy fit in the housing. If you buy the one-piece part of course this area of concern is obviated.

The bearing came out with a large socket as a spacer using a small bench vice. Not tight but not loose either.
That fits your description exactly.Thanks!
The only difference is that the old bearing has 2 internal races,I don't think that matters.

I've ordered from RS,should get it tomorrow.

Cheers all, N.
Logged

1984 2.0 Carb HPE [ex Aus] Grigio Finanza.
2007 Mazda 6 2.3 [current daily, highly recommended]
The past:
1980 2.0 HPE White in South Africa [hope it survives!]
1976 1.6 Coupe Lancia Blu [PFG 76R] [probably deceased]
oh,and an Uno Turbo 1997 also in SA [stolen,never recovered]
squiglyzigly
Hero Member
*****
Offline Offline

United Kingdom United Kingdom

Posts: 513



« Reply #8 on: January 27, 2020, 08:04:13 PM »

If the bearing you’ve ordered is the same number as on the outside of the old bearing seals, then it will be exactly right.  Single/double race, Size, plastic or metal cage, running clearance etc etc. It’s all in the numbers on the side. The designations for seal type and internal cage differ from one manufacturer to another but it’s very easy to cross reference online.

You’ll normally find bearings are cheaper to order by number rather than application. Unless you find some old stock being off loaded.

Sorry if you already knew this.

Ian
Logged

VX HPE (resto started Sept ‘21)
Beta Saloon 2.0l s2 1979 (completed July 2020)
Beta coupé VX (completed April 2017)
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
SMFAds for Free Forums
Valid XHTML 1.0! Valid CSS!