Well it's done; the engine rebuild. I didn't mess with the pistons, they were fine from what I saw. Yesterday I worked from 10 AM to 7 PM.
I began by uncovering the timing belt. Sorry no new pictures, to busy working; but seen here in the following picture you need to remove the harmonic balancer, #1 here. Ah, there's a bit more involved; the harmonic has the timing grove on it. You need to rotate the engine clock-wise until the grove lines up with top-dead-center.There are two engine rotations for T-D-C. One rotation would put cylinder #1 at low exhaust. That is not what you want. The #1 cylinder has to be at the max compression stroke, that's the other rotation. 180 degrees apart. The book suggests a cylinder pressure gauge. I don't have one. So I rely on an older trick. I find a dowel, and seat it into cylinder #1. I mark the dowel, rotate the engine to T-D-C. When the dowel is farthest out, that's the max compression. Leave the harminic pointed at T-D-C on the gauge in place on the plastic cover.
You've done that - or I have. I use a permanent white marker to document points of alignment. White dots everywhere. An excellent decision. Now, using an electric impact gun, and an old belt to stabilize the harmonic, I run the impact gun counter-clockwise on the bolt in the center to loosen it.
I then remove the many bolts holding the plastic cover in place, and moving a few odds and ends out of the way.
I find replacing bolts loosely in places the aren't in the way, and using separate cans for bolts I remove make things easier.
I recommend having a stool like a milk-crate to sit on, and a table for your tools.
With the plastic cover removed the timing belt, water-pump and many bearings and gear are revealed. Again, using a white permanent marker I make alignment marks, at least two. I do this to the crankshaft gear (that was connected to the harmonic balancer) to denote T-D-C, as well as the two opposite camshaft gears, marking their locations prior to removing the timing belt. Failure to do this will create a mess. The timing belt comes off easy, but then the camshafts relax a half to a full inch. To be able to install the new belt everything must line up. But that comes last.
Subaru's have a interference engine. Simply put it's different with a head on each side, rather than one on top, and if the timing belt breaks it doesn't destroy the engine.
Removing the first head, closest to the 1 in the image above wasn't real difficult. Loosening the 6 head-bolts was the challenge. Then I partially unbolted the intake manifold, and removed the head. The book says you must remove the camshaft and lifters also - a major pain in the ass. I saw no need to do that as the head-bolts are right there, and it worked out well.
With the head removed I could examine and admire it. I wasn't going to have the heads resurfaced - which is recommended, rather I carefully used a sharp and stiff scrapper to try and get as much remaining gasket free, using very fine steel wool in a few places. The less the better.
The gasket(s) that came off were ruined, and I could tell it wasn't from removing them. Fortunately there was no indication of anti-freeze in the pistons, which you can see with the head removed. The replacement head-gaskets I bought are Fel-Pro Perma-Torque. They are two steel sheets with a special surface. The old gasket was a single sheet of steel with a gasket type finish and that is what had failed.
Finally able to insert new gaskets for both the head and the head-intake manifold, and it's down to torquing 6 new bolts. Now the torquing sequence is new. I'm old school where you torque to a specific ft-pounds in a special pattern. But this Subaru, you use a torque wrench to tighten to an initial torque, then back off 180 degrees, then another 180 degrees, the torque two center bolts to this minor level, and the other 4 to half that. The use a angle torque tool (something completely new to me) to continue torquing first 80 - 90 degrees, then finish with an additional 80 - 90 degrees.
Wow, hope the first head I worked on is okay... it was a learning experience. I did much better with the other head.
Oil pan gasket now replaced also... and thanks to my fore-thought the timing belt is back on and if not for those position dots, the timing belt would have been a major head-ache. New water-pump installed, cover back on, harmonic reconnected - torqued using the impact gun in clock-wise. Ready to swap between engine stand to engine hoist, install new clutch, and reattach engine to transmission.
Oh yeah, and replace the drive-shaft.
I began by uncovering the timing belt. Sorry no new pictures, to busy working; but seen here in the following picture you need to remove the harmonic balancer, #1 here. Ah, there's a bit more involved; the harmonic has the timing grove on it. You need to rotate the engine clock-wise until the grove lines up with top-dead-center.There are two engine rotations for T-D-C. One rotation would put cylinder #1 at low exhaust. That is not what you want. The #1 cylinder has to be at the max compression stroke, that's the other rotation. 180 degrees apart. The book suggests a cylinder pressure gauge. I don't have one. So I rely on an older trick. I find a dowel, and seat it into cylinder #1. I mark the dowel, rotate the engine to T-D-C. When the dowel is farthest out, that's the max compression. Leave the harminic pointed at T-D-C on the gauge in place on the plastic cover.
You've done that - or I have. I use a permanent white marker to document points of alignment. White dots everywhere. An excellent decision. Now, using an electric impact gun, and an old belt to stabilize the harmonic, I run the impact gun counter-clockwise on the bolt in the center to loosen it.
I then remove the many bolts holding the plastic cover in place, and moving a few odds and ends out of the way.
I find replacing bolts loosely in places the aren't in the way, and using separate cans for bolts I remove make things easier.
I recommend having a stool like a milk-crate to sit on, and a table for your tools.
With the plastic cover removed the timing belt, water-pump and many bearings and gear are revealed. Again, using a white permanent marker I make alignment marks, at least two. I do this to the crankshaft gear (that was connected to the harmonic balancer) to denote T-D-C, as well as the two opposite camshaft gears, marking their locations prior to removing the timing belt. Failure to do this will create a mess. The timing belt comes off easy, but then the camshafts relax a half to a full inch. To be able to install the new belt everything must line up. But that comes last.
Subaru's have a interference engine. Simply put it's different with a head on each side, rather than one on top, and if the timing belt breaks it doesn't destroy the engine.
Removing the first head, closest to the 1 in the image above wasn't real difficult. Loosening the 6 head-bolts was the challenge. Then I partially unbolted the intake manifold, and removed the head. The book says you must remove the camshaft and lifters also - a major pain in the ass. I saw no need to do that as the head-bolts are right there, and it worked out well.
With the head removed I could examine and admire it. I wasn't going to have the heads resurfaced - which is recommended, rather I carefully used a sharp and stiff scrapper to try and get as much remaining gasket free, using very fine steel wool in a few places. The less the better.
The gasket(s) that came off were ruined, and I could tell it wasn't from removing them. Fortunately there was no indication of anti-freeze in the pistons, which you can see with the head removed. The replacement head-gaskets I bought are Fel-Pro Perma-Torque. They are two steel sheets with a special surface. The old gasket was a single sheet of steel with a gasket type finish and that is what had failed.
Finally able to insert new gaskets for both the head and the head-intake manifold, and it's down to torquing 6 new bolts. Now the torquing sequence is new. I'm old school where you torque to a specific ft-pounds in a special pattern. But this Subaru, you use a torque wrench to tighten to an initial torque, then back off 180 degrees, then another 180 degrees, the torque two center bolts to this minor level, and the other 4 to half that. The use a angle torque tool (something completely new to me) to continue torquing first 80 - 90 degrees, then finish with an additional 80 - 90 degrees.
Wow, hope the first head I worked on is okay... it was a learning experience. I did much better with the other head.
Oil pan gasket now replaced also... and thanks to my fore-thought the timing belt is back on and if not for those position dots, the timing belt would have been a major head-ache. New water-pump installed, cover back on, harmonic reconnected - torqued using the impact gun in clock-wise. Ready to swap between engine stand to engine hoist, install new clutch, and reattach engine to transmission.
Oh yeah, and replace the drive-shaft.
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