2002 Volvo S40, Camshaft Gear Replacement
Mark: Hi, it's Mark from Top Local, we’re here with Bernie Pawlik, Pawlik Automotive in beautiful Vancouver, BC where the rain never stops. So we're here talking about a 2002 Volvo S40, and what was happening with this smaller Volvo vehicle?
Bernie: This little Volvo, with the four cylinder turbo engine, had an oil leak. A very bad oil leak. It went from inside the timing cover area, the actual oil leak was coming from the cam, the exhaust cam shaft gear.
Mark: So how does oil leak from a cam shaft gear?
Bernie: Well, that seems a little unusual doesn't it? I mean well, think how can a gear leak? But this gear is actually a variable valve timing gear. And so inside this, the way a variable valve timing systems work they use engine oil pressure in these valves and they change the oil pressure inside the gear. That adjusts the valve timing. So it'll be set in a certain position. Then when you apply the pressure, it changes the position of the gear so you can adjust the valve timing. Kind of simple, but sort of complicated too.
Mark: So how common of a problem is that with Volvo's?
Bernie: Well this leak is not uncommon. These gears have actually they do create problems. They'll either fail internally or they'll develop a leak. The leak is not an uncommon issue. This particular engine seems to be more problem prone than others, but the other five and six cylinder Volvo's they used variable valve timing as well. Some of them have variable valve timing on the intake and the exhaust. So you'd have like two gears too that can potentially leak or cause problems. There's the added complexity of those as well.
Mark: So we have an extra treat today, we have a video and some pictures?
Bernie: We do have a video and some pictures. So let's start with the video. So there's the video with the covers off. This is actually after the repair and you can see that gear that I'm focusing on, the one on the left, it's sort of more silvery coloured, that's the gear that we replaced. It has all the variable valve timing components. The gear on the right is just a simple gear. It has nothing. It just bolts onto the cam shaft.
Let's take a little look around the top of the engine here with the engine covers off. You can see that the ignition coils and the spark plug wires. This item here, this is part of the variable valve timing as well. This is a sensor that senses the position of the cam shaft. So it sends a signal to the computer and that will determine how to adjust the valve timing.
This piece here, this is the variable valve timing solenoid. So this is an electrical connection here. The oil pressure goes up into the solenoid and that adjusts the pressure to the cam gear.
So we'll ditch this video and we'll go look at some pictures now of the gears. So there is the cam shaft gear. There's the old one. You can see this is a bit of oil. This just spilled out when we took the gear off. There's a cap here with a seal on it and that prevents the oil from coming out, but it's impossible to change this without making a mess. You leak where the red area points a little plunger that sticks out of the side of the gear. This is where the oil was leaking out of at quite a large rate.
I was actually just to sound a little bit more intelligent I wanted to figure out what the actual purpose of that plunger is because I did a training course awhile ago and the trainer talked about how a lot of these have a plunger or something to lock the gear under certain conditions. I believe that's what this is for but I could be wrong on that. Someone will probably correct me but there was a purpose to this plunger and yeah there's a seal inside there that's leaking. But of course this gear is all put together. It's a sealed unit. While the seal's probably worth a penny, it's a couple hundred dollars for the gear. There's things that can go wrong with them besides that issue.
Let's have a look at the ... There's another view of the gear. This is the inside view. This is what bolts under the cam shaft. Again, I'm point at the plunger here again so you can kind of orient yourself but the ... You can see sort of two sort of passageways here. This is where the oil is fed in under pressure and inside this valving will actually allow the gear to switch timing. So that is basically how it works and that's what we've got for sharing here. I’m back.
Mark: So with variable valve timing engines from other manufactures, how are they for ... I guess they probably use different systems for they’re all oil pressure activated and have the same sort of problems.
Bernie: They pretty well all use the same type of system. They're all oil pressure activated. These are leaks. They're not so common in a lot of other cars because Volvo uses a timing belt. They have for a long time. Although the new ones getting into sort of middle of the 2000’s they went away. They went to a chain drive, but a lot of vehicles that have variable valve timing have chain drives. So if something like this were leaking, like on the Volvo, you'd never know because the variable valve timing gear is located inside the engine.
But there are a number of problems with variable valve timing. I must say I pointed out a few things in that video. The solenoid, the sensors, there's a number of things that can go wrong with them. Timing chains stretching. There's a lot of issues in variable valve timing. It adds a lot of complexity to an engine.
Sometimes the simplest problem we run into and this is a lot of Hondas, Acuras, I'm thinking of, is people come in and they go, "the check engine light’s on" and there's a variable valve timing code, we go to check the oil and the engine's almost out of oil. People haven't been checking their oil. You can see how having a full oil level is critical to the function of the variable valve timing system.
So again, I've talked about oil changes. Change your oil and check your oil. Make sure the level's full. Not all cars have a monitor to tell you when the oil level is low. I'd say most cars don't. So you need to check your oil level. Don't just trust that it's working because running your oil low on an engine like this is critical. These are really expensive parts to fix so it's really important that you make sure that the oil is full. That's one of the biggest things we notice, but there are lots of things that could go wrong with it.
Mark: So variable valve timing, what does that actually do? What does that accomplish? What's the result of having it in a car?
Bernie: The result is better engine performance, better fuel economy, reduced exhaust emissions. That's the end result but what it is and what it does, engines have intake and exhaust valves to let the air into the engine and exhaust out. The timing of those valves is critical to engine performance. When an engine's at idle, it doesn't necessarily need the same valve opening as it does when you're trying to race down the road at 6000 rpms. There's a real ... The engine has different needs. So variable valve timing fulfills that. So you can get way better fuel economy, engine performance and gas mileage depending on how you adjust the valve timing. On an older engine, the valve timing was fixed. It was the same at any speed. So there's a compromise in performance. Variable valve timing takes the compromise out.
Mark: How are S and V40 Volvo's for reliability?
Bernie: I'd say they're not the best cars out there. There are a lot of things that go wrong with these cars. Transmissions wear out, it has a timing belt, it's a pain to change. You get these leaks from various places. So oil leaks, excuse me, they're not the most reliable cars out there. They're a nice little car when they work well it's a good car, but it wouldn't be my first choice for reliability in a car.
Mark: I understand that Volvo is making a pretty drastic change for the future. What's going on there?
Bernie: Yeah so I believe it's 2018 or 2019 they're actually coming out with a full line of electric cars. Now I read the press release and it sounds like in the press release, the whole company's going completely electric and you'll never see a gas engine again. That's not the case, but they are going to a full line of electric cars. I guess we'll have to see what that actually means but it's a pretty bold move. So they're trying to get to the forefront of that movement.
Mark: So there you go, if you're looking for service for your Volvo in Vancouver, the guys to see are Pawlik Automotive. You can reach them at 604-327-7112 to book your appointment or check out their website pawlikautomotive.com or our YouTube channel Pawlik Auto Repair and we've got hundreds of videos on there for all makes and brands of cars. Thanks Bernie.
Bernie: Thanks Mark.