Bearing play?

[SSmith]

how much bearing play (if any) in the serpentine belt pulleys is normal?
300TDI disco 185000km

i had my serpentine belt off today checking up on the power steering and water pumps i recently replaced

much to my disgust the only bearing in the whole system that DOESN'T have any play in it is the viscous coupling bearing

currently;
Alternator (bearings changed 2 1/2 years ago) very slight .5mm ish play in the pulley
Power Steering pump (new pump fitted 3 months ago) very slight .5mm ish play in the pulley
Water pump (new pump fitted 3 months ago) very slight .5mm ish play in the pulley
Tensioner pulley, changed it today - could see the seal was stuffed (last changed when i did the alternator)

is this normal or is something wrong

[87County]

HI,

is the play sideways or lengthwise.....??

if it's the replaceable bearings, I think ( from memory ) they are all 6203 (ie all about $5-$7ea), .... why not replace them all for peace of mind?

[SSmith]

sideways play

well id rather not pull everything apart again, unless i have to, especially the power steer and water pumps which are only 3 months old!
all bar the water pump are replaceable altho im not keen on pulling apart the power steering pump.
yeah ntn6203 sealed bearings, the back of the alternator is a little smaller, the number is on aulro somewhere

[PAT303]

They sound alright to me. Pat

[SSmith]

cheers pat
anybody else?

[paul-defender]

hi,
used to own a disco 300 tdi and had to replace all the bearings at the front at about 160k the alternator bearings were replaced 3 times in 6months, if the idler pully bearings are on the way out they load up the belt which seems to kill the alternator bearings. after fixind idler pully bearings which seemed ok the alternator stopped crapping bearings. this is just what i found

[SSmith]

which do you refer to as the idler? im guessing the tensioner pulley
AFAIK crank output, viscous coupling, tensioner, alternator, power steer and water pump? not including the air cond idler that is

[paul-defender]

yeah sorry meant to say tensioner. been a few years since the truck ran into it so my mental picture of the belt configuration is a little rusty. i found the bearings generally rumbled before they died. i am not certain that the alternator was fixed as it was only in a couple of months before the truck hit it but sounded ok. could be that the people that pushed them in for me the first few times damaged them.

[isuzu110]

I've just replaced the whole dayco serpentine belt tensioner as I could not get rid of the belt squeal (even after replacing the bearing, and the belt). The new tensioner had quite a bit of play in the bearing from new. I found this a little disconcerting, but hey, the squeal has gone.

Seems some play is normal.

[SSmith]

cheers
i did the tensioner sunday, sounded a little rough
i could accept the alternator needing re doing, its been nearly 3 years since i did it last
still not too happy bout the water pump and the power steering having a little play in them after only 2-3 months

disco v truck.... ouch, glad ur ok

[paul-defender]

i think with ball roller bearings it is impossible to remove all play.

[SSmith]

Thanks

[Pierre]

Not only the tensioner bearing will cause squawk. The tensioner itself, if worn, will contribute to premature bearing failure(s) by changing belt alignment.

Check that the tensioner is serviceable. Telltale signs are the splitting of the rubber insertion, misalignment of the fixed and moving parts.

HTH

Pete

[warren9981]

These bearings are a C3 spec which means they have a bit more clearance (read play) than normal bearings.:)

[SSmith]

thanks guys
ill have to have a better look at the tensioner assembly
sounds like its normal tho :eek: