DIY: Head Gasket Replacement

[winterfourever]

This is a DIY guide to taking apart your engine to replace the head gaskets... I also take apart some extra things along the way so if you see something that might have been unnecessary... it probably was! But in the end it all works out.

I will post a list of the parts you will need along with a decent place to get them in a little bit...

Let me know if you have any questions or suggestions! I also have the torque specs for every bolt, so let me know if you need to know anything.

(DISCLAIMER: I am in NO WAY responsible for the outcome if you begin this sort of project on your own. I am not a licensed professional, just an enthusiast and I don't pretend to be one. I'm not responsible if you hurt yourself, someone else, or wreck your engine/car along the way. I just wanted to post my experience and help out others who might want to tackle this themselves. Be careful and try not to do anything stupid!)

Just so you know, I did this at about 130,000 miles. I'm now almost up to 160,000 and my RS is still running strong!!! No problems, so this turned out good for me and saved me a ton of money, rather than having my local shop do it. If you are careful and do your research, it's not a hard project at all and shouldn't take more than a couple days if you already have the parts. It does help to have someone to help out too.

Here's what we will start with... the removed engine. If you can put it on an engine stand, it makes it a lot easier going forward.

Here's the DIY guide I did for removing the engine: http://forums.nasioc.com/forums/show....php?t=1991595



Note: I removed the clutch and pressure plate to get the engine to fit the engine stand. Other stands will let you mount the engine without removing the clutch and pressure plate.


Drain the Oil


The timing belt is going to have to be removed eventually. So start with the timing belt cover.


Here's a shot of spark plug central...


Remove spark plugs, and bolts holding it down


Unplug it and remove the distributor


The next two pictures show what each side of the long block look like after removing the spark plugs. Now, remove the hose that is on each side.

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[winterfourever]

Time to remove the fuel rail guards. They have a bunch of bolts holding them down so be sure to remove all of them.



This is what you'll be looking at after removing the guards.


Start removing the bolts holding the intake manifold to the headers... There are a lot of them


I decided to remove and dismantle pretty much everything so you can unplug and remove this now as well.


More things to unplug...

[winterfourever]

More intake manifold bolts






Unplug and unbolt everything attached to the throttle body. Then unbolt the throttle body and remove it. You will be looking at this.

[winterfourever]

Don't forget to unplug the timing belt sensor.


At this time you should be able to pull off the intake manifold along with all of the fuel lines and wiring. Most of it is all attached together. Be prepared for the intake manifold gaskets to stick to the cylinder heads and manifold... you'll have to replace these so don't worry about it.





Now you can remove the timing belt. Once you get the timing belt cover off, you will be able to see all the pulleys. Take note of the belt pattern.
Since you will have everything apart, I recommend getting a new timing belt and pulleys. If you just do it yourself right now, it will be a lot cheaper than having a shop do it or having the belt or pulley break down the road...


Remove the pulleys and belt and you'll be looking at this...

[winterfourever]

I've posted these three pictures for reference. The STRAIGHT LINES are the timing marks. When you put the timing belt back on, you will need to line these marks up the marks on the headers and short block.

The timing mark here is marked with blue and is at about 10 o'clock


Here it is at about 11:50 o'clock


Here it is at about 11:45 o'clock


Back to the cylinder head covers... Remove the 5 bolts and gaskets holding them on. Then remove the covers. Expect some oil to drain out when you pull the covers off.


This is what you will see with the covers off.


Now you will have to remove the 6 cylinder head bolts (2 have non-colored heads, 4 have red-colored heads) holding the cylinder heads on. These bolts are heavy duty and very long. These are also 12-point bolts so make sure you have a very strong 12-point socket and decent size breaker bar. I used the same breaker bar and floorjack handle extension to get these off. Get ready to put all your weight on them. Also, be ready to hear some that sounds like a "crack". This is normal and is the bolt breaking loose from its position. It means you're getting somewhere! DO NOT use an impact gun... this will snap the heads off the bolts and you will be screwed... Be patient and careful.

Once you get the cylinder head off you'll be looking at this. Here you can see the head gasket which was leaking at the bottom... =(


Carefully set the cylinder head aside. You might want to put the cylinder head cover back on so no dirt gets around the valves and camshaft.


Here's a pic with the head gasket removed...


Same process for removing both cylinder heads, so go at it!

[winterfourever]

I decided to go further and remove the coolant pipe. It's held on with 4 smallish bolts.


Here's what it looks like with the coolant pipe off...


We decided to try and clean everything up the best we could. This is my good buddy taking cleaning to the next level

[winterfourever]

We spent a while cleaning the pistons and everything up. Looks a lot better to me... Top and front cleaned up decently as well.

[winterfourever]

After cleaning up the intake manifold and pieces, I put it all back together so it would be ready to go back on once the cylinder heads were put back on...



Cylinder heads all cleaned up...



Short block all ready for new gaskets and the cylinder heads. Often you will want to get the cylinder heads resurfaced so that the surfaces will fit perfectly together with the new gaskets. I however didn't... Maybe should have, but I'm not having any problems a good 30,000 miles later so it worked out so far!


These are the new gaskets. I will post a list of parts with part numbers and prices as well as the site where I got them from (subarupartsforyou.com)


Make sure you put the gaskets on the right way!!!


Time to put the cylinder heads back on. This is the OFFICIAL pattern for doing the head bolts. This is straight out of the Subaru Service Manual.

(1) Apply a coat of engine oil to washers and bolt threads.
(2) Tighten all bolts to 29 N.m (3.0 kgf-m, 22 ft- Ib) in alphabetical sequence. Then tighten all bolts to 69 N.m (7.0 kgf-m, 51 ft- Ib) in alphabetical sequence.
(3) Back off all bolts by 180 degrees first; then back them off by 180 degrees again.
(4) Tighten bolts (a) and (b) to 34 N-m (3.5 kgf-m, 25 ft-lb).
(5) Tighten bolts (c), (d), (e) and (f) to 15 N.m (1.5 kgf-m, 11 ft-lb).
(6) Tighten all bolts by 80 to 90 degrees in alphabetical sequence.

CAUTION: Do not tighten the bolts more than 90 degrees.
(7) Further tighten all bolts by 80 to 90 degrees in this sequence: E -> F -> A -> B -> D -> C

Note: In order to keep track of the degrees I turn, I marked the starting position of each bolt with a sharpie on the bolt head and the actual cylinder head. Just pay attention!



Put the cylinder head cover back on and you're almost there!

[winterfourever]

Exact same process for the other side.



Now time for the timing belt!

First put in your new pulleys and tensioner. DO NOT pull the pin out of the tensioner. But if you do, use a c-clamp to push it back down and put in a pin so there will not be tension at first.

Line up the cams and the crankshaft as follows:




Each straight, imprinted line is pointing directly up and matching the imprinted line on the short block and headers...

Here's the belt pattern in case you forgot:


Also, note that the belt is directional!!! Make sure you put it on correctly! Cams and crankshaft turn clockwise...


This is what you should be looking at!

Note: I took the liberty of putting the intake manifold on at this time too. Seems like a good time for it anyways


Don't forget to put the belt guide back on!

[winterfourever]

Time to get the engine back in!

Thanks to my friends Dave and Jack (from the left) for helping me out and providing me with a space and tools to do this! Thanks guys!


Check out my new Samco hose set. Yes, I know this set is for a WRX/STI but the large hoses fit perfect. If anyone wants the ancillary hoses, I'll sell them to ya! Just let me know...


Get that clutch and pressure plate back on!



Where the engine's going...



Mount that thing back up! After lots of huffing and puffing and the motor finally settles on down...


Reinstall the alternator, AC Compressor, and Power steering pump in the same way they came off... along with anything else you took off.

Should be EASY if you labeled everything!!!!!!

[winterfourever]

I added a blue NGK spark plug wire set to spice things up and match my Samco hoses... I know that blue hose in the middle wasn't made for that but it works perfect and looks a lot better than the lame black...


Finish putting everything back together and presto! You have your Subie back up and running in no time!




Let me know if you have any questions... Happy to help out! Good luck!

[txl146]

Thanks for the write up. Excellent guide.

[williaty]

Oh god, that's why you removed the bumper. I wouldn't have put it back on if I were you

Many notes:

1) The things you keep calling "headers" are the cylinder heads. Heads for short. There's a big difference and you've likely confused the hell out of people.

2) You did way more work than you had to. The intake manifold and all the fittings on it can stay in place. A deep socket with a 6" extension on it will allow you to reach in between the intake runners and remove the inner bolts. You can leave the manifold resting on the top of the block during the whole process. Really, you took a whole lot of time and complexity there that you didn't need to.

3) You need to get the sealing surfaces for the head gaskets way cleaner than that. Those little dark areas are sites for potential future HG leaks. Subaru HGs are stupid fracking picky about how well you clean up. All around the sides of the shortblock, all under the heads, needs to be spotless.

4) To go along with #3, Using some Permatex Copper Spray-A-Gasket on the HGs will DRAMATICALLY increase the chances of a successful long-term repair. That stuff is fracking awesome.



On notes to other people;

a) If you're at a point where you need to do this, it it's worth doing other required services in the area. For instance, all new timing belt/tensioner/idlers, new water pump, new oil pump, new front main seal, new valvecover seals, new spark plug pipe gaskets, reseal the oil pan, cam seals, etc. There's a lot of stuff that tends to go out at about the same age as the HGs and it's WAAAAAY cheaper and easier to fix while you've got the engine out of the car anyway.

b) Make very, very sure you do every thing you can to keep track of where the dirt you're making is going. You don't want to end up with stuff you're cleaning off falling into the oil or coolant passageways.

c) If there's a surface with a gasket or a seal against it that you removed, clean it SPOTLESS. If you "broke the seal" on a seal or a gasket, replace it. It's an utter, utter bitch to have to pull the engine back out because your lazy ass didn't clean the top of the head well enough and now you've got an intake manifold vacuum leak.

[winterfourever]

Thanks williaty for the guru advice! I went through and changed all the "headers" mis-references... sorry about that! Yeah I know I did a bunch of extra stuff, but the stuff was simple and straight forward so I thought I'd relate my total experience of what I did as best I could...

For future reference, what would you use to clean up the cylinder heads and shortblock surfaces???

[09rexwagon]

Brake cleaner or isopropyl (70%) alcohol and some elbow grease. I've only done HGs on 350 Chevy's and D/B series Hondas, but I generally don't stop cleaning the block/head surfaces until I'd be willing to eat off of it . And yes copper spray-a-gasket works wonders on HGs.

[williaty]

I use a combination of solvents and fine-grit sandpaper on a known-flat surface. You can get all the way there with a green scotchbrite pad though. You just have to, as I said, be really careful to make sure nothing falls into the engine.

[RPKennedy]

I appreciate the photo DIY for this procedure as I am about to undertake it during the summer of 2013. My '02 WRX wagon is going through coolant like grass through a goose. Cobb Stage II w/AEM intake, if it matters.

Question: Was there, if fact, a list of parts required for head gasket replacement? I've read through this several times and haven't seen it. Saw the reference for SubaruPartsForYou.com

My hope is that someone sees my post and helps with a reply. I'd like to have all of the parts ready to go when I begin.

Thanks.

[winterfourever]

Originally Posted by RPKennedy

I appreciate the photo DIY for this procedure as I am about to undertake it during the summer of 2013. My '02 WRX wagon is going through coolant like grass through a goose. Cobb Stage II w/AEM intake, if it matters.

Question: Was there, if fact, a list of parts required for head gasket replacement? I've read through this several times and haven't seen it. Saw the reference for SubaruPartsForYou.com

My hope is that someone sees my post and helps with a reply. I'd like to have all of the parts ready to go when I begin.

Thanks.

Here's a link to the kit that you can get from subarupartsforyou.com: http://subarupartsforyou.com/cp_part...p?partid=10863
The gasket kit is about $187.

Call them just to confirm that it is in fact the exact right kit for your car. You will need the headgaskets, intake manifold gaskets, valve cover gaskets and all the grommets (all included in the kit). I highly suggest doing a full timing belt service at the same time since you will already have it off. That includes the timing belt, all the idler pulleys, tensioner pulley, water pump, and thermostat. I didn't do the water pump and thermostat, but should have.

Also, if your shortblock and cylinder heads mating surfaces are in rough shape, I would take them or at least the cylinder heads to a machine shop to get them resurfaced. I didn't do this and didn't have any issues, but to do it right that's most likely what you'd want to do.

Good luck!

[RPKennedy]

Your rapid response is greatly appreciated, as is the link for the parts list.
Did a complete timing belt service last summer, and will definitely get the heads and maybe block resurfaced. I inadvertently allowed my car to overheat and probably toasted the heads. May end up replacing them. We'll see.
Thanks again.

[02wagonrex]

what about using a hone to resurface heads and block?

[Camafuzzy]

cool very detailed

[ian.maines]

As mentioned before, you want to be real careful about getting stuff in your engine. Might want to rinse it off before you start taking it apart, just to get a lot of the sand/dirt buildup off. I love the photo DIYs, I'm thinking of recording any service I do to my vehicle to post on Youtube. Lots of good stuff there too!

[jarl]

The link to the ultimatesubaru site opens up a page with an alternator :/

Is this the kit? I can't find an itemized description of what's included... I assume it has the 633 head gaskets? What about the camshafts/crankshaft seals?

I can't believe it went up in price $60 in one year

[hockymad1]

quick question:

If you did some how snap the long bolts that connect the Head to the cylinder housing, how would you get them out?

....Or would you just replace the whole housing?

[quazimoto]

Originally Posted by hockymad1

quick question:

If you did some how snap the long bolts that connect the Head to the cylinder housing, how would you get them out?

....Or would you just replace the whole housing?

You mean the engine block? That would be the last thing I would do. There are various ways of extracting bolts depending on where it broke. The easiest of course is if you remove the head and you have some of the bolt sticking out of the block.