Belt tensioner questions

Discuss any maintenance you've done to your Vibe & Matrix and ask how to perform maintenance on your vehicle
Post Reply
mysteriousem
Posts: 22
Joined: Thu Dec 15, 2016 8:57 am
Location: Lubbock, TX
Contact:

Belt tensioner questions

Post by mysteriousem »

So, my '09 Pontiac Vibe is at about 101k, and I've been on a mission to do all the maintenance I need to do before I take a big trip in January. (Along with some neglected things the previous owner failed to do...)

I've noticed that there seems to be a belt squeal when I start up the car, and when the engine is running, there seems to be a kind of chattering/chittering noise that appears to be coming from the serpentine belt. There is also some vibration, even when idling.

I did some research, and I think it's probably about time to replace the serpentine belt. In fact, it's probably overdue... I think I'm up to the task of doing it myself, but I have a few questions for the GenVibe hive mind. :>

1. Should I replace the belt tensioner at the same time? Google seems to have mixed feelings about this, and I'm not sure I have the experience to know whether it really needs to be replaced or not. Some people say to go ahead and replace it every time you change the belt, others say wait for symptoms. What do you guys think?

2. Any advice for things to watch out for? I've been doing pretty extensive research before attempting any of these jobs, but I'm still a newbie to doing my own maintenance. Do you know of any big, common errors that newbies often make doing this job themselves? Or is it pretty straightforward as long as I do my research?

3. I know the new belts are expected to last 60-100k miles... But I haven't seen anything that gives a timeline in terms of how long you can expect the rubber to hold out if you aren't putting a lot of miles on it. Obviously, this one lasted at least 7 years without a catastrophic failure, but it's also clearly overdue to be replaced. I'm likely going to put fewer miles on it than the previous owner did, so should I aim to replace it every 5 years, regardless of mileage? Or should I just wait until I notice symptoms, and replace it then?
mysteriousem
Posts: 22
Joined: Thu Dec 15, 2016 8:57 am
Location: Lubbock, TX
Contact:

Re: Belt tensioner questions

Post by mysteriousem »

Annnd, I kept Googling and poking around at old forum posts... And it looks like maybe I don't even have a belt tensioner? :lol:

It's a 2009 1.8L, fwiw.
gtv237
Posts: 387
Joined: Fri May 23, 2014 6:21 pm

Re: Belt tensioner questions

Post by gtv237 »

No you don't have a belt tensioner. You adjust the alternators position to adjust belt tension.

I would take water from a hose or spray bottle and spray it on the belt. If the squealing goes away then there is a pulley alignment issue, likely a loose idler or water pump bearing. If the squealing gets louder then it is a belt tension issue which would indicate a stretched or under tensioned belt. It might help to have an assistant rev the engine to 2000rpm while you are performing this test.
mysteriousem
Posts: 22
Joined: Thu Dec 15, 2016 8:57 am
Location: Lubbock, TX
Contact:

Re: Belt tensioner questions

Post by mysteriousem »

Well, the belt squeal goes away on its own after a couple of seconds. It only happens at start-up for a couple of seconds. Guess I could spray it and then start up and see if it goes away? But if I'm understanding how the water thing works, I think that might not work?
jolt
Posts: 945
Joined: Sun Mar 02, 2014 2:07 am
Location: Twin Cities, Minnesota

Re: Belt tensioner questions

Post by jolt »

When you have the belt off, check that all the pulley's spin free and smooth. Tension the belt properly. If the belt is loose it will do what you are describing, and if the belt is to tight it could take the bearings out on the pulley shafts.
mysteriousem
Posts: 22
Joined: Thu Dec 15, 2016 8:57 am
Location: Lubbock, TX
Contact:

Re: Belt tensioner questions

Post by mysteriousem »

Thanks for the input. :) I changed the belt today, and it went a lot smoother than expected.

I think this job appears more scary than it actually is (*knock on wood*). When I first took the belt off, I wasn't sure it was going to make a big difference, because it didn't seem visibly worn. Boy did it make a difference, though! The nasty squeal at startup is gone, and it's idling a little smoother than before. I've also noticed I get a bit more power for acceleration, but that might be in my imagination...

In any case, thanks for the info, guys. Now on to the next project! :mrgreen:
Post Reply