Subaru Timing Belt Replacement Tips & Advice

Subaru Timing Belt Facts

  • Subaru 2.5 DOHC and SOHC are interference engines
  • Subaru timing belts are due for replacement at 105K
  • Oil will shorten the life of your timing belt
  • The water pump should be replaced with the timing belt

When replacing the timing belt on a Subaru 2.5L SOHC or DOHC motors there are a few common things to look for and I have some tips to help you get through the job even if you don’t have the factory tools. If you’re interested in buying factory tools Subaru uses Kent Moore for their specialty tool manufacturer. Otherwise keep reading for some quick and easy Subaru timing belt tips and tricks.

What to look for when replacing a Subaru timing belt

Subaru timing belt recommendation is at 105K but it’s not common to have to replace the timing belt before this mileage due to oil leaks from either the cam seal’s or front crankshaft seal. There are other spots to check such as the oil pump and the large piston access 12mm allen head bolts in front of the block also leak oil sometimes. Now as far as the rest of the components go I almost always recommend the water pump to be replaced due to mileage and there are a few timing belt idler pulleys you need to inspect for bearing noise. If any of these pulleys don’t spin smooth or make bearing noise when you spin them then replace them. There is a cogged idler pulley that bolts to the water pump and I always recommend this pulley with the water pump just because this is the first one to go out because of the load it has from the belt. The other pulleys are not under as much tension so they’re usually good for a while. Last you need to inspect the timing belt tensioner for bearing wear on the pulley and also inspect the hydraulic portion of the tensioner for leakage. If the hydraulic fluid were leaking from the tensioner I would replace it. I have re-used them this way before but unless your experienced with the tensioner these tensioners hold on the belt I wouldn’t gamble, this is an interference motor.

Now it’s time to get to the timing belt to inspect all these parts we know now to look for. First challenge, break free and remove the front crankshaft pulley. Now these bolts are very tight from the factory and require a lot of torque to break them loose. How are you going to hold the pulley from moving to break it free? You could use the special Kent Moore tool or just take a breaker bar and 22mm socket on end of crank bolt, wedge the breaker bar next to the battery and crank the motor over. I would remove the battery hold down and place something over the transmission cooler lines to protect them if they’re present. Take a look at this pic to get a better idea:

crankbolt breakerbar

Breaker bar on the front crank bolt

Now you have the covers off and your ready to start taking off the timing belt. Before you get ahead of yourself you need to break loose the cam gear bolts and this is done best with the timing belt still on. Get a couple clips and attach them to the belt/gear to prevent the belt from jumping when breaking free the bolts. Now reinstall the crank bolt and turn the motor till the timing marks align. Install a 22mm wrench to the crank bolt and wedge it up against the alternator pulley. You can now break free the cam gear bolts with a breaker bar or whatever.

Replacing Subaru Cam Seals

So, you need to change the cam seals, water pump, inspect the timing belt tensioner and idler pulleys for wear and replace as needed. Most of these parts are sel explanatory for replacing except for the cam seals. You’re probably wondering how to remove them. We’ll there are lots of different techniques yu could use and I’m not going into detail about that because there are just so many different ways you could get them out. I use an actual cam seal puller.

cam seal puller

Here is a picture of the cam a cam seal puller. A cheap investment that could save you from an expensive repair.

I used to use a pick too, but no matter how you decide on how to remove them just be careful not to scratch the camshaft because it can cause the seal to leak. Not too long ago I had a customer in with an oil leak that was just that, he scratched the camshaft while removing the cam seals so just be careful.

Subaru Timing Belt Tensioners

The last thing I will tip you on is how to compress the hydraulic tensioner for the timing belt. All you really need is a decent bench vise that opens far enough to fit the tensioner in it and slowly compress the tensioner careful not to force the piston; you will fell the tension release after a short wait with each turn of the bench vise. Once the tensioner is compressed all the way use a small long allen key and slide through the lock pinhole. The picture below shows a compressed tensioner using the factory lock pin, which if you buy a new one it comes this way so you wouldn’t have to worry about compressing the timing belt tensioner at all but they’re not cheap. As faar as replacing the tensioner just inspect for bearing noise from the pulley and leakage from the hydraulic cylinder, either of those and you should replace the timing belt tensioner. I have seen Subaru timing belt tensioners go bad and make noise like an engine knock.

timing belt tensioner compressed

Subaru timing belt tensioner compressed in a bench vise. Pin locked and ready for installation.

That pretty much sums up all I have for now, if you like the article leave me a comment or ask a question. I’m always happy to answer them. Don’t forget to like my page too, thanks.

This post was written by: Martin Hand

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Martin Hand

About Martin Hand

ASE Certified L1 Advanced Mastertech. Martin Hand has over 15 years experience in Asian and European Import Auto Repair. Specializing in electrical diagnosis, engine performance, AT/MT transmission repair/rebuild. Martin is also pursuing a degree in Computers Science & Information Systems starting at Portland Community College while he plans to transfer to OIT. Certified in Java application level programming, experienced with other languages such as PHP, Ruby, JavaScript and Swift. Martin has future plans of automotive diagnostic software development.

142 Comments

  • Brittany says:

    Im doing a Timing belt kit replacement on a 2001 subaru legacy outback that is going to be going into a 2004 impreza. Do I have to put the ’04 drivers side Cam gear and Crank gear onto the ’01 engine? Additionally, do you know if the intake off the ’01 will work with the ’04? Any help would be great. Thanks!!

    • Martin Hand Martin Hand says:

      I cannot help you with interchangeable Subaru parts without seeing it for myself. If your swapping I would use everything from the 04 vehicle that it’s going in just to be safe, intake assembly, wiring harness, computer and anything else I may have left out. The cylinder heads could even be different, later models use variable valve timing. The short blocks are basically the same but there are differences also.

  • Sandy Farley says:

    I am an older woman with my 3rd Subaru that is 16 yr. old. Altho’ the “old girl” still runs fine, I’m in the market for a newer model. Because replacement of the timing belt has always been a major expense for me I decided to research it, and in doing so, I ran across this site.
    Mr. Hand, thank you so very much for this very important instructional article. I honestly believe that I could probably replace a timing belt, et.al. based upon what you’ve stated here. Thanks so very much!

  • Jeff Bledsoe says:

    When buying a timing belt kit that includes the tensioner, water pump, and pulleys, is there a difference for auto vs manual transmission? I have seen some kits for my 2003 Impreza TS (automatic) advertised as manual kits, but I thought the parts would all be the same…

  • David Darabosh says:

    Doing a timing belt 2013 WRX brand new OEM belt tensioner should this unit be bled before installation or should it be installed and just pull the pin?
    Thanks for any input
    David

  • brett says:

    I have recently purchased a 2003 2.0 gx station wagon with 103000 km/s on the clock , where is the best place to order in a complete timing belt and water pump kit in south africa , if in south africa at all ?
    and where would i find the engine series number , i was an audi owner and am now a proud owner of a Subaru
    any hints or tips will be appreciated

    • Martin Hand Martin Hand says:

      You can order from any website just make sure they are good made in Japan brands. Mitsuboshi timing belt and Asin water pump they are good brands. Just try to stay away from the made in China parts and if you use any seals buy Subaru parts only.

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