2009 Honda Accord V6 Serpentine Belt Routing Walkthrough
Replacing the serpentine belt on a 2009 Accord V6 isn't complicated, but if you get the routing wrong even once, the belt will just fall off and you'll be standing in your garage wondering what happened. I've done this maybe six or seven times across different years of these cars, and I still keep a reference card next to my toolbox because it's one of those things you think you'll remember and then absolutely forget at the worst moment. The 2009 Honda Accord V6 uses the J35Y 3.5-liter engine. The belt runs around seven pulleys total, and here's the order you need to follow: Starting from the bottom, the belt wraps around the crankshaft pulley first. From there it goes up and around the power steering pump pulley on the left side of the engine (driver's side when you're facing the car). Then it routes down to the A/C compressor pulley. From the compressor it goes across to the alternator pulley on the right side (passenger side). Above the alternator is a small idler pulley that the belt passes over. Then it goes to the tensioner pulley, which is located near the bottom between the crankshaft and the power steering pump. That's the one you push with a 14mm socket or a proper belt tool to release tension. From the tensioner it goes back up along the right side to another idler pulley near the top, and finally routes back down to complete the loop on the crankshaft.
2009 Honda Accord V6 Serpentine Belt Diagram
If you want a clean visual reference, Honda doesn't publish an official downloadable diagram on their service site for this particular year, but the routing sticker is normally located under the hood on the radiator support or the strut tower. On my 2009 Accord, it was faded to the point of being unreadable after about eight years, so I ended up tracing it myself with a piece of chalk on the engine bay surface while the old belt was still on. That's honestly the most reliable method I've found because photos online are all over the place and a lot of them are from different model years where the routing changed slightly. One thing people consistently mess up: the belt has a specific direction. Most modern serpentine belts have arrows molded into the ribbed side indicating the correct rotation direction. If you install it backwards, it will throw noise immediately and probably wear out in a few hundred miles. The J35 belt is directional, so check the arrow before you route it. There's also a groove pattern difference — the crankshaft pulley has a wider groove than some of the others, and if you try to force the belt into the wrong groove, you'll strip it. The tensioner on these is a hydraulic spring-type unit. It holds constant tension automatically, which is nice, but it also means you can't just eyeball the tension and call it good. When you compress the tensioner with your tool, the arm should move smoothly and return quickly when you let go. If it feels sluggish or doesn't spring back fully, the tensioner is going bad and you should replace it at the same time as the belt. I learned that one the hard way on a customer's car — replaced the belt, everything sounded fine for two weeks, then came back with the same squealing. Turns out the tensioner was on its last legs and only looked marginally weak once the new belt took load off it.
Tools you actually need: a 14mm socket with a ratchet or a dedicated serpentine belt tool, and optionally a extension bar if your ratchet won't clear the nearby components. The tensioner bolt is accessible from above but tight angles can be annoying. Some people use a breaker bar for leverage but that's overkill and easy to over-compress the tensioner. A standard ratchet is fine. The belt part number for the 2009 Accord V6 is typically 38X675 or equivalent (Gates K060675, Mitsuboshi 38X675). Aftermarket brands like Gates and Mitsuboshi are both solid. The OEM Honda belt will cost more and is essentially the same belt in a Honda box. I've run Gates on my own cars for years with no issues. Just make sure you get the 3.5L version — the 4-cylinder models use a completely different belt and routing. Here's a practical tip that saves time: before you remove the old belt, take a photo with your phone from multiple angles. Not because the photo will be perfect — it rarely is — but because having a reference makes it infinitely faster to double-check your work against when you're installing the new one. I've spent twenty minutes trying to figure out where a section of the belt went once because I didn't take that photo. It was just sitting right there on a pulley I'd missed.
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The whole job takes about 15 to 20 minutes if you know what you're doing and 45 minutes if you're fumbling around on the first try. The most time-consuming part is usually just finding the right angle to get the tool onto the tensioner bolt. Once you've done it twice, you'll know exactly where to reach and how to position the ratchet. If the belt is badly glazed or cracked, don't try to stretch the old one back on for reference after removing it. It won't lay flat and you'll misread the routing. Take your photo first, remove the old belt, lay the new one alongside it to verify the length and rib count match, then route the new belt following the sequence I described above. Double-check every pulley before releasing the tensioner. Make sure the belt is seated in the groove of each pulley, not sitting on top of it. After installation, start the engine and let it idle for a minute. Listen for any chirping or slipping sounds. If the belt noises persist after five minutes of running, the tensioner may not be applying enough force or the belt may not be fully seated on one of the pulleys. Re-check the routing and tensioner operation before driving it anywhere.
