replace pulleys with timing belt?

[RiverWolf]

Hi, it's (past) time to replace the timing belt on the 4Runner. Planning to do the t-belt, water pump, and serpentine belt as part of the service. Dealer says they inspect the idler/tensioner pulleys and crank/cam seals, but only replace if needed. Google doesn't turn up a definitive opinion either way regarding the pulleys/seals being a "while you're at it" kind of thing. Thoughts and opinions?

TIA.

-Brent

 

[The_Jeff]

Shouldn't need it. In a rubber/steel interface the rubber wears first.

If on the other hand you were doing a timing CHAIN you'd want new sprockets so they all wear together evenly.

 

[PandaBear]

I do it every time because it is cheap if you buy aftermarket (Koyo from rockauto is usually $10-20 only).

 

[Jim 5]

You may even want to change out the idler/tensioner. I had to do this on my '89 4Runner at 120k miles. If you're near those miles and have everything off anyway, it's good prophylactic maintenance. More convenient than doing it again when it fails.

 

[stephen9666]

I replaced the tensioner on my GF's VW when I did the timing belt. The tensioner/pulley are one part, so you end up replacing the whole thing.

If it's not a pulley that is integrated into another part, it shouldn't need to be replaced.

 

[Jim 5]

Originally Posted By: stephen9666
I replaced the tensioner on my GF's VW when I did the timing belt. The tensioner/pulley are one part, so you end up replacing the whole thing.

If it's not a pulley that is integrated into another part, it shouldn't need to be replaced.


On my Toyota, the tensioner/tensioner pulley was one part. The bearing in the tensioner pulley failed and I had to buy the new spring loaded tensioner arm with pulley.

 

[ltslimjim]

After having my timing belt fully serviced and put back together it was found that one of the pulleys for the drive-belt system was making some noise. It's a low squeal right now and doesn't make noise all of the time, but it wasn't making a sound before this was performed. So, it's not like the bearing just went out completely, but FWIW i wish I had known to replace it while they had the vehicle still to save labor.

 

[Herz]

Always replace, these are items that wear out and should be replaced with the belt.

 

[The_Eric]

Originally Posted By: ltslimjim
After having my timing belt fully serviced and put back together it was found that one of the pulleys for the drive-belt system was making some noise. It's a low squeal right now and doesn't make noise all of the time, but it wasn't making a sound before this was performed. So, it's not like the bearing just went out completely, but FWIW i wish I had known to replace it while they had the vehicle still to save labor.


Are you saying that after your timing belt was replaced, you noticed a new noise? If so, then it's likely that the belt is too tight and making a noise that I liken to "whirring"...

 

[mechtech2]

The gears should be cleaned really well.
The pulleys should be changed, or at least greased if you can.
Bad pulleys cause belts to go, no the other way around.

 

[Cause4Alarm]

Originally Posted By: eljefino
Shouldn't need it. In a rubber/steel interface the rubber wears first.

If on the other hand you were doing a timing CHAIN you'd want new sprockets so they all wear together evenly.


you forgot about bearings in the pulleys.....they do wear

 

[ltslimjim]

Originally Posted By: The_Eric
Are you saying that after your timing belt was replaced, you noticed a new noise? If so, then it's likely that the belt is too tight and making a noise that I liken to "whirring"...


Well, the mechanics noticed too(guys I trust) right after they put everything back together and heard the sound after re-start, and it was from the drive belt system, an idler pulley.

Had they known before hand they probably would've greased the pulleys(note they did a great job on everything in the timing belt job; (idler/tensioner/belt/seals etc)...No noise until re-installation from a non-directly related part. I mean, since it's got constant tightness applied to the drive belt from the pivoting pulley that moves during removal/re-installation, I don't know how it could be too tight. Only one of the pulleys in the system is now making noise.

 

[The_Eric]

So you're saying it's the accessory drive belt - like the one that drives the alternator?

 

[ltslimjim]

Originally Posted By: The_Eric
So you're saying it's the accessory drive belt - like the one that drives the alternator?


Yes, from my experience. So, I would advise the OP to replace anything related to this job, and have the drive system pulley be inspected for need of re-greasing.