17

Unfortunately there is no magic eight ball which can tell you how many miles are on a timing belt. This is my own opinion, but I'm sure it's shared by most: If you don't know the mileage of a timing belt on a car with an interference motor, change it. You can never go wrong. The one you are showing in the picture looks like it's been around the block ...


13

I think the main reason for this is convenience. It's an easy place to run the water pump. If you ran it out to a fan belt, it would be in the way of the timing belt while doing it, or it would be a really awkward mess trying to work around it. The second reason is for compactness. With the water pump stuck out of the way, it physically makes the engine ...


11

Belts are quieter but are often less obviously worn before they break (chains stretch and loosen, belts tend to stay tight without damaged belt teeth up until the moment they snap). Timing belts are also less complicated (chains require an oil bath). Chains are generally stronger, so vehicles with timing chains often drive more than just the cam with the ...


11

Engine safety. If you lose an accessory belt driven water pump, you're likely to keep driving, thinking the "oh, I just don't have an alternator" while you're busy cooking your engine beyond repair (normally with no temperature notification/change, if anything it'll read cold). When the water pump is on with the timing belt (or geared to crankshaft as is ...


11

I don't know if I deserve all this credit. My idea was sound, but my measurements were pretty bad so my numbers are way off. If you try this, use the more precise software that Robert S. Barnes ended up using and don't rely on a YouTube video to measure a belt spinning at 200 RPM! In your first video, the timing belt is going through 1 revolution per ...


9

Even if the timing belt is "probably" okay, you have to weight the costs and benefits of not replacing it. From what I can tell, this car has an interference engine, meaning if the timing belt breaks, the cylinders will smash into the valves. As long as they don't break off and also tear up the cylinders/combustion chamber, this is a difficult but doable job ...


9

You absolutely should have the water pump, tensioner, and idler bearings replaced at the same time as you have the timing belt replaced. Everything needed comes in a kit and costs a bit more than replacing just the belt alone. This is standard maintenance on most every engine you replace the belt on, because if the water pump goes bad between belt ...


8

tl;dr: a broken timing belt always means some sort of damage. Like Brian says, interference engines are obviously at risk of the most straightforward damage: pistons hitting valves with great energy, causing ma$$ive destruction. Here is a cautionary video illustrating some of the parts that can be immediately broken, causing a appalling domino effect of ...


8

Check with the manufacturer to see if it's an interference engine or not. Even so, that's not an absolute guarantee. Occasionally someone with an interference engine will get lucky and not have the valves and pistons attempt to occupy the same space at the same time. I've also heard anecdotal reports of non-interference engines suffering damage when ...


8

Yes, it is by design ... because it helps to equalize wear across the sprocket teeth and chain links. Here's why I had originally shared a link in the comments which presents the formula to calculate what's known as hunting tooth frequency. Mesh rate aside, this is governed by the the number of teeth in the sprocket and chain, a and b respectively: gcd(a,...


8

On non-interference motors there is no compelling reason to change out the belt on a schedule other than to ensure your vehicle does not leave you stranded at the most inopportune time. It will not damage anything if it does let go, but assume it will always leave you stranded. Something to think about here is to ensure you know exactly which type of motor ...


8

The belt looks okay, but @dlu is totally correct I'm not liking the track. The first photo it almost looks like it's rubbing on the inside of the cam flange. In any case, you can count the cracks on the belt teeth. If you bend the belt away from the teeth and see more that 3-5 cracks over a 1" span, the belt needs to be replaced. Get a Conti or Gates kit ...


7

You have the D16A6 engine. From searching various forums it seems that is an interference design. However, while valve damage is possible (probable?), it may not be certain. There do seem to be reports of timing belt breaks without valve damage. Then again, there are reports of bent valves, too (though that is a later 1.7L version of your engine). A break at ...


7

You don't weigh them against each other. Items are generally inspect or replace at x miles or y period of time, whichever comes first. This is what you need to do to keep the car within factory tolerances. Go outside of that range and you become a "test driver", which may not be an issue, but it could be for certain parts...


7

As they are made of rubber, belts begin to perish over time, and this weakens them. The constant flexing as the engine turns accelerates this weakening process. Eventually (if it weren't replaced), the rubber would split and the belt would snap - causing very expensive damage to your engine... It is quite easy to visually observe a belt that definitely ...


7

To answer your questions, if there is a real leak, then yes, there is a problem. The oil will cause the belt to deteriorate and possibly slip. When it does, it is catastrophic. Pistons slam against valves and the head is toast (in most cases). This does happen suddenly. Get a different shop to look at it. If the belt appears dry, I would bet there isn't an ...


7

You can have a look at the condition of the belt to gauge its condition. But you'll need to have seen quite a number of timing belts to be able to tell. The risk is that when a timing belt snaps, it damages your valves and pistons too. To fix that will require the engine be taken apart and the damaged parts replaced. It's not a cheap thing to do. Timing-...


7

As others mentioned: Change it, the belt looks suspicious (especially the position and the side towards the engine) and it is much cheaper than a new engine. Just for the position of belt on the sprocket: For certain types of spring tensioners it can happen, during installing, that the spring will get stuck between tensioner and engine block, thereby ...


6

Obviously the timing belt needs to be replaced. Then they could change any followers or guides which mechanically get worn out. I would always recommend getting the water pump changed if it is driven off of the belt, or located in the same vicinity as the belt. The reason for this is, if you have to remove everything to replace the pump (ie: timing cover, ...


6

The OP indicated in their comment that they didn't maintain timing in the process of replacing the timing belt. Since the 2007 Accord V6 has an interference engine, attempting to crank the engine over with the timing off will result in mechanical damage, which would explain why it is running roughly.


6

quick tip if any one is doing their timing chain or belt. make sure you have a picture showing the tdc( top dead center), double check all the marks match exactly no error is tolerated here, the crank, exhaust cams, intake cams etc. the tip is first throw the belt on the crank, then align the belt on the cam which ever is far away from the tensioner, then ...


6

On the Honda SOHC V6 engine when doing timing the mark on the crank sprocket should line up with a small arrow on the block @ 12 o'clock. The bank 2 cam gear should have the cylinder 1 TDC mark lining up with the indent on the backing plate. The bank 1 cam gear is pretty much the same as bank 2. It has an indent and a mark on the cam gear. A good practice ...


6

Echoing the advice you've already received, change it as soon as you can. I'm particularly concerned by the position of the belt on the sprocket and what looks to me like a wear line to the left of the belt. I would be happier if the belt was tracking closer to the middle of the sprocket and the wear line suggests to me that the belt is either moving back ...


5

Check around your engine bay. There may be a sticker indicating the last timing belt change if mechanic did stick it. Something similar to this.


5

That is usually caused by a tired ancilliary belt (the one that drives the alternator etc) - as the rubber ages, it grips less well and slips more against the pulleys, especially when cold and damp. After a couple of minutes it dries out and warms up, and so stops slipping. The timing belt itself is toothed, and so cannot slip (it would cause a catastrophic ...


5

BMW's plan was for it to never be changed. Looking at some of the forums, I think advice given from this BMW site seems about spot-on: Well-l-l, I hate to say "never" but the point being, one often needs/wants to crack open & rebuild an engine for other reasons (ring/valve wear, main seals, etc.) by a quarter-million miles or so--at which time, check ...


5

I wouldn't hesitate using an impact to loosen the crankshaft pulley retaining bolt. The reason for this is because even though there is an impact involved, it is a rotary impact. The crank itself would incur no damage, nor would the bearings. The bearings take a worse beating during normal operation than they would during crankshaft pulley retaining bolt ...


5

The key to your mechanic's response about changing the timing belt and water pump "now" is that you have no real indication of the maintenance history of the car. You don't know if it's been changed or not. A timing belt could last for that long, but who knows. The mechanic is giving sound advice because he's trying to help you protect your interests. Do ...


5

Here is a picture of what I believe your engine should look like: The red arrow should be what you are seeing. This is the serpentine belt which drives the accessories. The green arrow is the cover which inside is where the timing belt lies. There is no real way to tell if the timing belt has been changed. After a couple hundred miles of running on the ...


5

As the comment says, looking at the web site you posted there seems to be a couple of flavors of engine for your car. So unless we know the displacement (it would say 2.3L V6 for example) we can't say exactly for your car. There are 5 or 6 flavors listed for your car, from a 1.8L 4 cyl, to a 4.0L V8 ( would love to see how this is stuffed into a Passat lol). ...


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