I finally completed my timing belt replacement for my 2004 MDX. First time around at 105K miles, I had dealer do it as I wasn't confident. 2nd time around, due to price increase, I decided it to do it on my own (apparently, my “confidence” has a price). Here are some tips and suggestions that I thought it may be useful if you’re willing to take the challenge. This is not a step by step as I think there are plenty of those on the web but I thought some highlighted tips would be helpful.
1. Estimate the time you think it will take and double it.
I know some of you can do this in 5 to 6 hours. I’m not one of them. I gave myself the whole weekend starting on Friday night. Took 2 hours on Friday, 10 hours on Saturday, and 4 hours on Sunday, or total of whopping 16 hours. However, what I did was I took breaks in between in order to not to hurt my back, have background music on (such as Danza Kuduro) to pretend to be working in the shop with Dominic Torretto, vacuumed and cleaned engine compartment, and cleaned every part that came out before putting it back in. Really took my time to enjoy the process.
2. Get the parts and tools you need far in advance. Have backup tools as well. In addition to the typical various sockets and wrenches, here are some tools that were very useful.
Two ½” breaker bars, impact sockets (19mm for crank), PB blaster, craftsman 20 inch ½” extension, PowerBuilt crank tool, and 6ft pipe. I got the breaker bars and sockets from Harbor Freight. Some people make fun of them due to their price but things like breaker bar and sockets, they are really good value tools. Use the PB blaster to spray the crank bolt weeks before tackling this job. You can do this by turning the front wheels all the way to the right and using the red skinny straw through the star shaped crank bolt access opening.
Have lot of spare clips. Purchased from Ebay which was much cheaper. You will break the clips when you're taking the undercover/wheel well cover off.
3. Acura vs aftermarket parts.
My default has been always Acura parts as I know they work and they fit. But I came across this kit from Aisin (TKH-002).
The Koyo bearings and tensioner are exactly the same as Acura.
Water pumps are similar except Aisin’s exterior finish is not as nice as Acura/Honda.
I don’t think it matters. Also each fin blades of Aisin are slightly wider.
Timing belt is made by Mitsuboshi who are OEM supplier for timing belt and drive belt for lot of manufacturers. Quality looks very good.
I went with Aisin kit as you can tell.
I also purchased Bando drive belt and Acura thermostat separately.
4. Read and watch the timing belt replacement how to as much as possible before starting. These may not be exact to your model but it’s pretty close.
I’ve also read the MDX service manual which was not as friendly. You’ll notice that they skip steps as they assume you know what you’re doing. For example, they’ll note “take off front and rear timing cover” but not noting that I need to remove the power steering pump and the drive belt tensioner to do that. The manual also expects you to flip around to different pages to get these things done.
5. Friday night goal – take the crank pulley bolt off
As many have suggested, taking the crank pulley bolt off first is a good idea. You don’t want to be stuck engine taken apart if you can’t get the crank pulley bolt off. This setup (attached 6ft pipe to the breaker bar) made it smooth and uneventful. Soaking the bolt with PB Blaster for weeks helped.
6. Disconnect the battery – or if you’re replacing the thermostat, take out the battery and its casing. Since you’ll be disconnecting some electrical connections, it would be a wise move. Thermostat is connected to the lower radiator hose.
7. Stay Organized.
8. I kept a log so that I can work backwards. Only change in installation order was I did install the crank pulley on back before installing the front and rear TB cover so that I can manually rotate the crank/TB to verify timing is still ok. Also, I always kept checking the timing mark every time I completed a step.
9. When taking the drive belt tensioner off, don’t unscrew the large center bolt all the way. I did and when I pulled the tensioner out, I heard a “clink” and didn’t know what it was until I looked around in the engine bay. Found this white plastic nut that holds the large bolt, probably to make the installation easier.
10. Coolant will come out from the water pump even after draining the radiator. If you’re changing thermostat, coolant will drain out from there as well. Have lot rags and position the catch pan as best as you can.