Video: V-belt / fan belt identification and inspection

IPD goes over the functions of V belts, how to identify when one needs to be replaced and proper installation in rear wheel drive Volvos.

Video transcript

Okay, let's talk about v-belts and what they are what they do and how you know when to replace them and some quick tips on replacing. Volvo models that are the 279 series cars the red block cars they're a rear-wheel drive use v-belts and the reason they're called v-belts is if you look at the profile they kind of have a v-shape and these are used to drive your accessories and what I mean is your water pump, your alternator, your power steering pump (where applicable), and air conditioning (where applicable). 

So if you look down on this car we've got a Volvo 240 model here. This particular car has power steering but does not have air conditioning so it's going to have three belts. Just real quick identification that's going to be the same on the 279 series cars as far as what's there but the belt routing is a little bit different. We've got belts here and these ones run around this pulley which is the water pump. The alternators down there and then the crank is down there on that side so the spinning of the crank turns these belts which in turn turns the pulleys to pump air or water through the motor with the water pump and to generate the current off the alternator. On this side is for the power steering pump and you can see it also goes off the crank and goes over this way. 

Now when you're looking at these and you're not sure things to look for about when you might want to replace them things like that are gonna be really obvious things like if you hear the things squealing like crazy and you look under the hood and it's really loose and floppy and maybe flapping around in there. Also if you notice things like cracking on the edges if you look at this you can see if you see cracking around the edges here from being dry or if you see the thing become frayed around here it's got some fabric wrapping those are also signs that you need to change it.

Now if you determine that you do need to change them there are a few different considerations. On some of these things that's very easy because all you have to know is what year and model the car is and we've got all the listings and specifications for belt sizes on the ones, you need to order. On a handful of those specifically some of the late model to 240s there are a couple different options on belt sizes. That's going to be something where we're going to ask you to identify which size belt you have before you order to ensure you get the correct one. Couple tips on how to do that, now most view belts that you're going to get from somewhere like Continental which is the kind we carry and you'll find at most European auto part stores are gonna have markings like this on the belt now other ones might have is a slightly different style marking but they're all gonna have some of the basic information usually find a part number stuff like that manufacturer but the main thing to look out for here for this one example is going to be this number 13 (belt width) millimeters x 975 (belt length) millimeters. This particular one is going to be a 10 x 935 so those are just a couple of small things. And whatever's on your car you can usually still see that if you don't see it just rotate the motor around a couple times by hand or just bump the starter and then we'll be able to see those markings and know what sizes on there if there's a question.

So now that we've talked real quickly about how to ID if you need a belt and you've already identified which size belt to needle you have your belts and it's time to replace them what do you do. Well, first you get a good service manual because that's a must when you're doing any type of repair like this that's gonna give you your specifications on belt tension, it's gonna also show you the procedure for how to get the old belt off and get the new one on. 

Now that we're at that point let's talk real quick about some issues that can come up with tension of the belt because this one is something that comes up real commonly. So if you get it on there and the tension is too loose the thing will flap around that usually means a slipping belt which leads to some squeal and can also potentially lead to some glazing from improper belt tension. And that just means where it leaves a little bit of a glaze on the pulley or on the belt and that makes it much more prone to slip. In which case you got to take it back apart sand it down a little bit deglaze it kind of a pain so best to get it right the first time. Now in your service manual also find specifications for deflection of the belt how much it should move when you push it. Use that as your guide because on the other end of that if you end up too tight you can end up putting a lot more stress on the other pieces. You can wear out prematurely bearings on your pulleys on your alternator on your water pump and any other accessories and in some extreme cases - we've even seen people with belt tension too high that eventually leads to a sheared bolt in the block for a tensioner assembly. Now, of course, all those things are rare cases but setting your belt tension correctly the first time is a sure way to avoid any kind of future problems and to ensure that you'll have a quite smooth proper operation of all your accessories. 

If you have any questions on applications or belt install procedure just anything like that you can always give us a call and we'll be happy to answer any of your questions.