Thread: Idler bearing question

Also just a point of interest, ask for one with a "C3" speed rating it will last much longer with the rpm & heat, if it's a bearing going on an engine I always use C3 I work for SKF thats why I know.

Pity we can do this on the serpentine belt pulleys on P38As. The pulley is moulded around the bearing and it seems the bearing can't be replaced. LR don't sell the pulley alone, one has to buy a complete tensioner assembly.

Ron

DEFENDERZOOKhey wortho.....you got yourself a defender yet...?
Not yet, but i just saw a black 90 for $27k and couldn't stop drooling only 65,000 k's.Only problem is i couldn't bear to sell my Disco and i can't afford to get one, yet.
Tony i also just came back from doing that rock step you busted Lurch on 30psi and she went straight up also the other climbs there on 30psi no hesitation no probs( i had 40psi when we were there). so still pretty stoked with the Disco. But god i'd love a Defender!!!!!!.

C3 is the clearance rating is it not?

wouldnt have thought 100c would have a bearing (pardon the pun) on a bearing to any great extent...


at what temp does a C3 get to the normal toleranced bearing size?

Originally Posted by incisor

C3 is the clearance rating is it not?

wouldnt have thought 100c would have a bearing (pardon the pun) on a bearing to any great extent...


at what temp does a C3 get to the normal toleranced bearing size?

Yes C3 is for non standard internal clearance, not a speed rating.

In most cases either the outer ring or the inner ring is a tight fit in the housing or on the shaft, depending upon which is rotating relative to the load direction. The other ring is then normally a location fit.

The fit on the tight ring reduces the internal clearance to an acceptable value.

However where there are heavy vibration loads loads, such as vibratory feeders or crushers, it is necessary to have a tight fit on both inner and outer rings. In this case the fit of the rings,will reduce the internal clearance too much, leading to overheating of the bearing and failure.

In these case, bearings are manufactured with greater than normal internal clearance, eg. C3, to allow for the reduction when both inner and outer rings are tight fits in the housing and shaft.

Originally Posted by incisor

...wouldnt have thought 100c would have a bearing (pardon the pun) on a bearing to any great extent...

100 deg C is reaching the limit for many greases used to lubricate bearings.

The upper limit for calcium based grease is usually 60 deg C. 80 deg C is usual for Sodium based grease. 110 deg C for Lithium based grease.

Originally Posted by p38arover

Pity we can do this on the serpentine belt pulleys on P38As. The pulley is moulded around the bearing and it seems the bearing can't be replaced. LR don't sell the pulley alone, one has to buy a complete tensioner assembly.

Ron

I don't know what the idler pulleys on P38's are like.

If like the 300Tdi, they are the same size (and same bearings) as idler pulleys on Commodore V6 engines.

ok guys quick question here the main belt tentioner on the 300tdi has developed a squeal in so i am guess that teh bearing is buggered as u guys suggest it's very easy to change the bearing but would like if somebody could give me a quick guide on how to do this ?? does the while tensioner need to come off??? or just the wheel that houses the bearing
i know it's more then likly a lot easier then i am expecting just not something i don't want to screw up also the bearing numbers quoted are for teh 300 tdi correct??? thanks as always guys


Worraps