Just replaced both belts on 2008 Fx35 infiniti.

ANSWER : Hey Dan, thanks for inquiring. I don’t know that you necessarily need to replace your pulleys, neither tensioner or idler. However, if you are hearing a squeaking from your engine and suspect the pulleys are the problem then replace them as needed. I don’t think you really need to replace pulleys every time you replace the belts.

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.

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 : More likely mileage and time wore the tensioner out. The tensioner bearing wears out with mileage – it’s good to replace the tensioner pulley/bearing when replacing the belt. The tensioner itself is spring-actuated, and the spring can get weak over the years. The squeaking is likely from the tensioner bearing itself. If you decide to get it fixed, consider YourMechanic, as a certified technician can help you replace your belt tensioner as necessary.

ANSWER : The parts are touching likely because either the parts were not installed properly or fasteners may be missing or broken. If oil has been leaking, this can cause the seal around the covers to swell as well causing misalignment. Consider hiring an experienced technician like one from YourMechanic who can come out and take a closer inspection of the belt drive to see what is causing the misalignment and offer a more personal diagnosis as well as estimate the proper repairs.

ANSWER : Hi there – there is actually a 3rd answer that is best. Infiniti doesn’t make AC compressors (nor does most any other auto manufacturer). These are made by 4Seasons, Sanyo, Denso, Hitachi, etc. Replacing the compressor correctly means getting an original AC compressor supplier part, which probably won’t have an Infiniti sticker on it. Still the original spec part, and your best value long term. I recommend an AC compressor replacement performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

ANSWER : The water pump and timing belt should be replaced as a set if the coolant leaked on the belt. The coolant leaking on it will damage the belt.

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.