Hi! Dne’ here once again! I believe that if a person is willing and able, then we should tackle maintenance on our vehicles vs taking to a dealer or local garage. It does require some common sense when taking “things” apart, and being able to put it back together again, and of course a variety of tools! Like any good mechanic, I have a vast variety of tools! I love tools! ; )
Note: I performed this maintenance procedure a few years ago, but had the pictures on file and decided to put this on Classic Cars and Tools.
Here, our ’02 Subaru Outback with the 3.0 flat 6 cylinder was getting close to 95k miles, and really nothing had been done to the engine about spark plug replacement and O2 sensors, and fuel filter. But the Outback also did have an oil leak coming from both valve covers! do I really want to attempt this! yeah!
I love the look of this engine, and the engine cover! Especially after washing it and applying a little Armorall! First mention in taking the engine cover off~ visibly there are I believe several 10m bolts on the top, but after removal of these, pull the engine cover forwardly, then up, then it can be lifted up and out easily. On ours some goofball didn’t pull it forward and broke the front retainer clips! argh
Henceforth, I will not be going in order of a step by step process. I didn’t document every detail, but the most important is mainly how to gain access to the plugs; )
The quest here is how do I get these spark plugs out! Much less the valve covers!? One has to remove the coil packs which are over each spark plug! The coil here is recessed low and difficult to get to! hmmmm
First, one has to jack up the car and put some jack stands for safety! Here I bought a new plastic thing that goes beneath the engine. Ours was destroyed by oil changing places and general wear. The new one looked very nice and was only about 80 bucks from the dealer. Notice I didn’t say 79.95. I despise everything these days are like, 19.95, or a car for 29,995.! give me a break!
Note: there is a sound deadening material on the other side(not shown). Maybe you can see part of it that has come loose in the old cover. That material gets very nasty especially if your engine has an oil leak. This old oil gets heated up by the exhaust and engine heat and can smell, the smell can make its way to the engine cabin~ then you may get a whiff of burning oil from time to time. Fire hazard? Who knows! Check your valve cover gaskets!
Once the car is up on jack stands and the lower engine cover is removed. You have to disconnect the exhaust from the exhaust manifolds. There are only six nuts and maybe an exhaust hanger back a ways. Just let it gently hang down. Then there are two nuts that need to be removed that secure the engine or motor supports. Now one side at a time, the engine may be raised. Here I used a bottle jack placed on a few blocks to elevate the bottle jack. You must find a solid place to jack the engine from, then SLOWLY raise one side of the engine, I said one side at a time! ; ) This will raise the engine and the spark plugs to where they can be more easily accessed. More easily, not necessarily easy ; ) Now don’t go crazy thinking you can raise the engine higher than necessary~ there are hoses and other things connected to the engine as well. Just go slowly and only as high as needed.
Note: the nuts that hold the engine supports are a shallow nut, and your socket can easily slip off. Use a good tight fitting socket. I used my air impact and came off fairly easily, but if you’re using a wrench, might be a little testy! ; )
Take a close look at this picture below! Notice all the oil residue on the frame and crossmember~ That’s from the leaking valve covers~ugh~ makes my skin crawl that this poor engine has been so neglected! : ( but I have the technology, I can make this better! ; )
Important Note: Though it may not be absolutely necessary to drop the exhaust, I must have deemed it necessary, otherwise I wouldn’t have dropped it (disconnected it from the exhaust manifolds). But while going back over my blog last night, and you should decide to do as I did and drop the exhaust, please put a baggy over the exhaust or stuff a rag in it~ so there won’t be a chance of dropping a nut or bolt down it! Gives me nightmares! ; )
The spark plugs are actually easier to remove if replacing the valve cover gaskets! there are several 10 mm bolts that hold the valve cover in place, then the valve cover may be removed and cleaned up in preparation for new gaskets/o-rings gaskets. The coil packs are each held in place by a 12 mm bolt. Unbolt it and the coil pack can be unplugged from the plug and moved out-of-the-way. Be sure to put the coil pack on the same plug you took it from! Doah! The picture below is the passenger side of the engine.
Important! When re-installing the coil packs on to the spark plugs, put some Dielectric or connection grease on the part of the spark plug where the coil pack plugs on to. Just a little dob. Little packets may be purchased at the counter at auto parts stores, you don’t need a great big tube of it!
With the valve cover removed, the spark plugs are staring you in the face and easily accessible with the correct sized spark plug socket(with a protector inside so not to damage the ceramic part of the plug). Remove the plugs and install your new plugs now, be sure to check the gap before installation. You don’t want to have to pull the plugs back out for another 80 k miles, right?
Important: When installing the new Spark plugs, don’t forget the Dielectric(mentioned later or earlier), but also place some anti-seize compound on the threads of the spark plugs! Don’t get crazy with the stuff and don’t get it on the electrode tip of the plug! You do want the spark plugs to be able to be removed again some day, right!? ; )
Here on the driver’s side, the battery and other un-boltable things need to be moved out-of-the-way to access the valve cover and plugs. You must remove the windshield washer tank and battery. One or two of the valve cover bolts were a little testy to get out, be patient, they’ll come out. Another part to replace while you’re at it is the fuel filter, right behind the windshield washer reservoir, plus the fuel filter will be easier to access with the reservoir out-of-the-way! : )
Also a great time to clean up where the battery sits! Please wear long sleeves on the side of the engine, the battery residue can mess with your skin, you may want to at least take a moist rag and clean this area before the task at hand.
Now my dear car DIY friend, if you’re not going to replace the valve cover gaskets, just replacing the spark plugs, then do so, but make sure the valve covers aren’t leaking!!
below: this is on the passenger side. Here one coil pack removed, you can just make out the hole where the spark plug lives, kind of like a Hobbit! lol Got to have a little fun, right! Don’t think of this as a chore, it’s an accomplishment! You can do it! ; )
below: this is the driver’s side bottom of the valve cover. Notice the oil drops hanging from it! These little oil drops drip onto the exhaust pipe and smoke and smell! Replace the valve cover gaskets! Now, this is another good time to replace something else, The O2 sensors! There are three of them, and they are quite expensive, but necessary! I just replaced the two up front. Notice the blue wire? which leads to the driver’s side O2 sensor. I won’t go into detail here in its removal, pretty much common sense to remove it if you’ve made it this far. Be sure to put some anti-seize compound on the threads.
below: This is a great time to clean up the valve cover and make it look new once again! I love clean parts! Buy your new gaskets from a local Subaru dealer, I don’t believe your local auto parts have them. I do believe in factory parts despite the price. Just think how much money you’re saving by doing this job yourself! Personal satisfaction and knowledge attained! 😉 As far as putting sealant on the gaskets? I don’t believe it’s necessary. I did put some permatex thinking I was doing myself a favor, but the permatex smelled for a long time! These are machined surfaces, just put the valve cover back on like this and all should be well.
This is actually the finishing up of the job of replacing spark plugs and valve cover gaskets. The engine is clean once again and maintenance goal achieved. Be sure to write your own service order and the parts purchased and keep a record. If you don’t, amazingly you’ll get down the road many miles later and ask yourself, “When did I do all that work?” haha! Keep good records!
PS: if you should ever have a growling power steering when turning the steering wheel, it usually means it’s sucking in air, and usually happens at the pressure hose. The o-ring becomes old and allows air to be sucked into the system causing the noise! very irritating!
I hope this has helped, and thank you for coming to Classic cars and Tools! If this helped, would you please leave a nice comment, and maybe even subscribe! ; )
Your car enthusiast friend! dne’ ; )