The Infamous Subaru 2.0L & 2.5L Turbo Exhaust Pulley Nightmares
If you have worked on one of these and had to remove the exhaust cam pulleys then you may be aware of these problems. On the camshaft pulleys they switched the 17mm bolt head to a 10mm allen head bolt. The bolt has a huge flange on it as well so it doesn’t like to come off. If you read the factory torque specifications and actually try to torque it to this then you would understand why there is this problem. The torque procedure states to torque 22.1 ft.lb then turn 45 degrees. If you try to torque it to this you’ll quickly see that it is way too tight. I only torque them to 70 ft.lb and have never had a problem and they’ll come off if you need to get them off, but they still like to stick regardless. Keep reading and you’ll find some helpful hints to overcome this problem.
The tools that you will need are a stubby ½ drive 10mm Allen socket and the camshaft pulley holder specialty tools. AST makes a good set of camshaft pulley holders for these engines; these are the ones I recommend to use but they make a lot of different styles. Take a look at the pictures of these tools to get an idea of how they work. If you look online under Google images you will find that they have a few different styles of gear holders but these are the best ones you can get for the Subaru turbo engines in my opinion.
Now, how to you tackle the problem when you get one that wants to strip? You cannot add heat to the bolt because the cam pulley is plastic and DO NOT try hammering the bolt head to loosen the threads like you would on normal stuck or seized bolts. You will break or crack the cam thrust bearing plates and those camshafts are not cheap. The first tip is to buy some valve-lapping compound and put it on the Allen socket, it will help to grip the bolt and not strip it when you really crank on it. So this will save a lot of them from stripping out the allen if you’re lucky and have a good socket. Remember it needs to be held straight as possible when wrenching on it hard (this is why to use the stubby allen). If this doesn’t work then it’s not coming off easily. At this point your going to have to cut the bolt for removal. Sometimes you can save the pulley but you’ll find out it takes too much time when trying to save the pulley. The cost of labor is not worth the price of a new camshaft pulley so I just cut them and replace both. If your lucky you can save the pulley but usually spend all this time trying to save the pulley and it will need replaced anyways so just cut it off and take your looses. Just make sure not to cut too deep on the pulley where you damage the camshaft. I use a 6” electric grinder with a cut off wheel. Takes about ten minutes, once you cut the bolt flange it releases the tension on the bolt and you can chisel it out. I use my air hammer with a chisel bit and knock it around counterclockwise for removal (careful not to damage camshaft if using air hammer). I’m curious as to any other tips and/or experiences from our readers. Please leave questions or comments below, thanks.