1999 V70 serpentine belt ?

[T5erry]

As much as I’ve searched for the answer to the following questions, I hope this isn’t a repost.

1999 Volvo V70 T5 approx. 154000 miles

So I bought a Continental brand serpentine belt from a popular parts store we’re all familiar with to replace the worn serpentine belt on my car. As soon as I pulled the serpentine belt out of the shipping box I noticed a difference in the two sides of the belt. I wondered what the difference was and began to look closer at the belt. As you can see in the picture one side looks almost sparkly as if there are fine pieces of fiberglass shining in the light. The other side appears to be just flat black in color and have no sparkle.

Still trying to figure out the difference I put my finger on each side to see if it felt the same; it doesn’t. If I put my finger on the “sparkly” side, pushing down and sliding my finger across the belt it feels like rubber (makes since to me). If I put my finger on the “flat black” side and slide my finger across the belt it feels more like, for lack of a better description, slippery felt.

At this point I’m thinking that when the belt is installed the rubbery side goes against the crankshaft pulley, a/c compressor, generator, and power steering pump. This makes sense to me because I’m thinking the side that is rubber will have more grip to not slip as the crankshaft spins or the a/c compressor cuts on/off. This means the other side of the belt (what I’m describing as the flat black side that feels slippery) will ride against the idler and tension pulley. This also makes sense to me since the idler pulley is just a guide and the tensioner pulley is only keeping tension on the belt (both are freewheeling).

Even though this all makes sense to me I decided to call the parts supplier just to confirm my thoughts. The gentleman I spoke with told me it should be installed opposite to the way I have described above (i.e. he said to install the rubbery side against the idler/tensioner pulley and the slick side goes against the crankshaft pulley)

While I respect what the gentleman says I disagree with him, but since he is the one working at the auto parts store I don’t know who is correct?

I searched many posts on MVS trying to find mention of the correct way to install the serpt. belt to only find many posts where people are having new problems such as belts jumping and squeaking noises after installing their new belt. Is this because they installed the belt backwards?
I’ve looked outside of MVS and still can’t find mention anywhere about the correct way to install the belt.

A definite answer on the correct way the belt should be installed would be greatly appreciated!
Also, are the belts directional? (I can’t imagine they are or I would see an arrow somewhere on the belt).

Thanks for your help!

[cn90]

According to Conti, the belt is symmetrical:
http://www.pic.ctapps.de/web/en/ART_040 ... D=6DPK1841

Anyway, try one direction, if it makes noise (I doubt it), switch direction (mark it with Sharpie before removing it!).

[T5erry]

Thanks for your response cn90.

I know it’s crazy to put this much time/effort into a serpentine belt. The reason I’m trying to find a definite answer is because it appears to me there are two distinctly different sides (i.e. inside and outside) of the belt. Yet when I search on MVS and other forums I can’t find any mention of such. I can’t find any mention of such on the link you provided from Continental. However, what I do find in several posts of members changing their serpentine belt is they suddenly have new squeaks/squeals or the belt is jumping. While I understand some parts often wear simultaneously, I suspecting some members problem is because the belt was put on “inside out”.

It was only by coincidence that I noticed a difference in the sides because I laid the belt under a bright desk lamp. If most are like me you’re not normally in the most well lit conditions when working on your car. Therefore it would be very unlikely to notice the difference especially with greasy hands or wearing rubber gloves.

I considered going by my local Volvo dealer just to look at the factory belt to see if it was the same as the Continental, but they don’t have one in stock. Over the phone I explained to the part’s guy what I’ve written here and he too wasn’t aware of the belt having a front and back side. The parts guy I was speaking with used to be a Volvo mechanic for what that’s worth.

Although it’s hard to see the different wear rates of the two sides in the pictures I’ve included it is oblivious there are two different sides/wear rates on the belt when looking at the belt in person.
The picture with the oblivious cracks are of what I believe is the inside or rubbery side of the belt going around the idler pulley. The second picture is of what I believe is the outside of the belt or the more slippery felt like side going around the power steering pump pulley.
While the power steering pump pulley is a good bit larger and wouldn’t expose or cause the cracks to open up as much as on the smaller idler pulley I can only see the faintest cracks beginning on the what I’m calling the outside/slippery felt side of the belt. Again very different wear rates because of what I believe is two different materials used for the inside/outside of the belt.

If no one chimes in with a definite answer or firsthand knowledge in the next day or so I’ll go ahead and change my belt out the way I believe it should be and see what happens.

Thanks again.

[JKXC]

Sorry for bumping the old thread, but I have this same question. One side of the belt for my '05 XC70 2.5T is bejeweled-like sparkly, the other is matte. I think I'll go writing side down for now which is the matte. But odd there's so little documentation about this elsewhere. I'd be curious if anyone has some opinions... Thanks

[abscate]

Letters on the outside. I don’t think the bedazzling has a mechanical relevance