Belt keeps on sliding off and breaking the belt.

ANSWER : Hello. Dodge unfortunately had a strange history with this issue in one way or another. The type and quality of belts you are installing may be playing a factor, and you may want to upgrade to a better belt. The type and quality of belt tensioner you installed could also be playing a factor. A smooth belt tensioner surface is subject to the belts sliding off, especially if there is any liquid in the area. If the water pump, oil, or power steering pump are leaking fluid, then the belts are more prone to slipping off and becoming damaged. If you need to have this scoped out, have a local expert, like one from YourMechanic, inspect the belts and make proper adjustments or repairs as necessary.

ANSWER : Hello. The smaller belt is known as your timing belt, and it works inside the engine to keep mechanical components aligned with each other during the compression cycle. The serpentine belt, which is the big belt, drives the alternator, water pump, AC compressor, and a couple of other components. If the small belt broke it is likely the timing belt. This will cause the car to stall, lights to illuminate, and can even cause serious damage to the engine. Typically replacing a timing belt is a lot more complicated and expensive than replacing a serpentine belt. You may want to receive a second opinion on the car before you go ahead with repairs.

ANSWER : Hello. If this all started after the alternator was replaced, then that is more than likely the problem. If the alternator is defective and has an internal bearing failure then this will occur. Also, if the alternator is not mounted correctly, then this can happen. I would have the shop warranty the alternator and that should take care of it. Alternatively, a qualified professional from YourMechanic can come to your home or office to diagnose the recurring alternator problem in person.

ANSWER : This is okay since there are more notches on the belt than the amount on the sprockets. Once you aligned the first time the belt marks will almost never line up perfectly again. The marks are used to put the belt on correctly. They aren’t used as an indicator after the engine is turned again. You should be okay to start the motor as long as timing marks on pulleys line up. If you run into any issues, have a certified technician, like one from YourMechanic, assist you with the replacement of the timing belt.

ANSWER : Check to be sure that the new belt is actually the right part number or, better yet, use an OEM (dealer) belt. Also, be sure the tensioner is the right part number or use an OEM sourced tensioner. Check to be sure that all of the pulleys and accessories (e.g., alternator, water pump, A/C compressor) that are driven by the serpentine belt are all operating in the same plane. It is not unusual for the pulley on the crankshaft harmonic balancer pulley to move (generally outward) relative to its original position. The pulley is rubber bonded and over time can move. If that pulley moves, that means that the belt groves are no longer running in a perfect plane and that alone can cause slipping. If you request serpentine belt inspection a certified Mechanic, dispatched by YourMechanic right to your location, will identify the problem and thence get the issue resolved for you promptly. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : Hello. Yes you can replace the water pump without replacing the serpentine belt. If the belt is worn, and it breaks while you are driving, you can damage a lot of other components in that area. Typically the price of a serpentine belt is relatively inexpensive. You will have to remove the belt to replace the water pump anyway. Since you are likely going to have to purchase a new pump, we do recommend that you purchase a belt at the same time. You SHOULD replace the belt if it is worn, and this is a perfect time to do it. It is not necessarily required, but you are putting yourself at risk of another break down at a later time. Not to mention if the belt is already worn, manipulating off and back onto the vehicle while changing the water pump can further damage it, and shorten the amount of time its got left. Belts should be replaced before they break, as to the amount of damage they can cause when they do break. Again, you may be able to get away with not replacing the belt right now, but if its as worn as you say, its going to break sooner than later and should be replaced.

ANSWER : Usually, by the time a Mercedes drive belt is ready to be replaced, the tensioner is shot too. If you haven’t replaced the tensioner, than you should. If the pulley that was replaced was in fact tensioner, then you need to look at the individual devices. If you have an AC compressor or an alternator that is trying to lock up, the extra load on the belt will make it slip, and eventually burn up. Additionally,if any of the mounts are loose, causing alignment issues, then the belt will not last very long. As a final thought, make sure the routing of the belt is correct. Some of these belts are routed like a Rube Goldberg mousetrap and it’s possible to fit the belt up in several ways, but only one of them is right. If you decide to delegate this work, you can contact Your Mechanic to have a technician come out to your home or office to check out your car and take care of your belt for you.

ANSWER : Hello. If the belt driving the A/C compressor only drives the A/C compressor and nothing else, you can remove it with no consequences. The fan shroud is not optional equipment however as it has both a cooling system function and a safety function.

Depending on your climate, you might consider diagnosing the A/C system and repairing it. If you use a service such as YourMechanic, it will often be economical enough to do it, particularly if the fault is limited.

Even if the compressor shaft sealing is leaking (would be likely after 25 years), that is fixable in the field. Feel free to contact YourMechanic if you have additional needs relative to this or the replacement of your power steering, alternator, A/C belts.