Replace Serpentine Belt Auto-Tensioner every time?

[SteveSRT8]

We do extensive stationary operations at 1700 rpm and thus replace a lot more belts than most duty cycles. I have had tensioners last a tremendously long time, easily a quarter million miles or more.

Take them off the vehicle and inspect them carefully. Obviously if they are bad they will waste your new belt quickly.

 

[PandaBear]

Originally Posted By: The Critic
Originally Posted By: MONKEYMAN
I just went through this scenario on a 99 SL2 with 216,000 miles. Noise when cold. The tensioner had 100,000 miles on it and I replaced it again. Then noticed grooves on idler pulley. That was cheap to replace and bearings were noisy. Also replaced the belt. If it is high mileage I would not forget the idler pulley if it has one...


Don't use a Gates tensioner, they will rattle horribly...at least they did on my '96.


I've used them twice and they are fine. You likely got a bad one.

 

[MONKEYMAN]

Originally Posted By: The Critic
Originally Posted By: MONKEYMAN
I just went through this scenario on a 99 SL2 with 216,000 miles. Noise when cold. The tensioner had 100,000 miles on it and I replaced it again. Then noticed grooves on idler pulley. That was cheap to replace and bearings were noisy. Also replaced the belt. If it is high mileage I would not forget the idler pulley if it has one...


Don't use a Gates tensioner, they will rattle horribly...at least they did on my '96.


I bought it at Napa. The counter person with 30+ years experience said he did not see returns on them, just their cheaper brand. It looks similar to the original. What I found interesting is the belt from Napa was a little short for the tensioner they sold me. The Dayco belt from Autozone I bought when getting the idler pulley was the correct size. Tpitcher found out when replacing the belt on cremepuff.

Napa belt too short


Seems like I fixed the problem, but I should have replaced idler pulley first, since it seemed to have bad bearing. MechTech2 gets my vote for best answer.

 

[The Critic]

Originally Posted By: PandaBear
Originally Posted By: The Critic
Originally Posted By: MONKEYMAN
I just went through this scenario on a 99 SL2 with 216,000 miles. Noise when cold. The tensioner had 100,000 miles on it and I replaced it again. Then noticed grooves on idler pulley. That was cheap to replace and bearings were noisy. Also replaced the belt. If it is high mileage I would not forget the idler pulley if it has one...


Don't use a Gates tensioner, they will rattle horribly...at least they did on my '96.


I've used them twice and they are fine. You likely got a bad one.


The aftermarket belt tensioners for the S-Series vehicles are notorious for being inadequate.

 

[MONKEYMAN]

Quote:
The aftermarket belt tensioners for the S-Series vehicles are notorious for being inadequate.


That is correct. I could not wait to ship in an OEM one, plus not keeping the old girl much longer. I still have the OEM tensioner I replaced if this one goes south. I would go to the Saturn Dealership but they only sell Fiats now.

It was the idler pulley bearing anyway. Time will tell how well the tensioner holds up.

 

[Cujet]

My jaguar x-type just lost the water pump belt due to idler failure. The engine overheated and cracked a cylinder head. All of this happened within minutes. By the time the light was on, the damage was done.

Engine ruined due to a $18 pulley and bearing assy.

 

[The Critic]

Just did an 2004 Accord tensioner today, for the sake of preventive maint. Book time on it is 0.9, but due to my sausage fingers and lack of dexterity, it was a two hour ordeal. A simple belt r/r takes 10 minutes. I can see why many people skip the tensioner if all seems well - it is often a lot of extra hassle and expense that is difficult to justify.

 

[zzyzzx]

In my 1995 Escort I replaced it with a new OEM one at around 200K miles, but I could have kept the old one in. In my 1999 Alero, which mostly just sits, I've already replaced it. IMO, I am more concerned about the spring weakening over time more than anything else.

 

[DinoOil]

The last time I replaced my serpentine belt, I most certainly changed my tensioner. I had no choice at that point in time. The tensioner disintegrated, tore up the belt along with it, and caused coolant to spew out. I think it's a good idea.

 

[01rangerxl]

When I bought a Dayco W belt for my truck a few months ago it had "Replace belt tensioner!" taking up most of the sleeve. I didn't.

At 15K miles or so my truck had the original belt and tensioner replaced under warranty for noise. I changed the belt a second time at around 125K miles as PM, but the tensioner seems to be working fine, so I'm leaving it alone. Seems like they can go bad at any mileage anyway.