SilentJ20s spec.B gets a new short block!

[SilentJ20]

Ok, I meant to make a post a while ago, but this is now starting with a dump of everything from the beginning to now:

On May 31st, I noticed a cloud behind me, along with poor performance (no boost, rough idle, etc).  I returned home from work to oil purging itself from my dipstick hole.

Now, this struck me as odd as oil usually is needed to stay INSIDE the engine.  The following day I started it in the garage with the oil fill cap removed to see if I had any crankcase pressure.  Enter, the little engine that could...

CHUGGA CHUGGA

I don't have a video of the rear of the car, but this is a pretty close approximation:

Apparently, somewhere along it's lifetime my spec.B decided I was worthy enough to witness the absence of rings in a cylinder.  The magic lights in the dash and a code reader reported cylinder 4 with a misfire condition.  While sourcing a new, OEM short block at a price that didn't make me consider conduct of questionable legality, I started the extraction and disassembly process of the boxer-shaped boat anchor currently residing in my engine bay.  Quick shout out to the power steering and AC system being designed so they do NOT need to be disconnected to remove the engine!

New block, seal kit and coolant!

Once the necessitated teardown level was achieved, I discovered the main culprit.  Look Ma!  No ringlands!

Along the way, I discovered the clutch was on its deathbed and a CV boot nearest the turbo was beginning to split and release its precious lube contents.  However, I was pleasantly surprised to see that the oil and coolant had remained completely independent of each other.  No forbidden milkshakes.  And there was no sludge in the oil pan.

Other than the obvious, the block showed remarkably little wear for almost 140k miles.  Crosshatching was present in all areas other than the blown ringland.  The boxer block really is a neat thing.  It's very compact  Maybe not the lightest complete assembly in the world, but once the heads were off I could say I finally lifted an engine block onto my workbench (don't worry, I did use an engine hoist and stand for the work).  Cylinders 1 & 3 did have some significant carbon build-up, though.

I obtained an OEM STI clutch and flywheel after freeing myself from the grip of Analysis Paralysis comparing all my available options.  I know there are LOTS of available parts to mod these cars for increased power and such.  But since I will be keeping this car at stock power levels I used almost all OEM parts unless a reputable alternative was available for a lesser price.  This included extra parts needed like spark plugs (because now is a great time), rubber breather hoses that had solidified into brittle plastic, the PCV valve, tools, and other misc. odds & ends.

I got the heads resurfaced and cleaned, a mechanic buddy took my oil pan and valve covers to his work to solvent wash them in their tank.  Now, this is where I owe my friend a LOT.  He's a good friend and a mechanic at a local Subaru dealer.  He uses factory specs and sealants (as opposed to 'good enough') and takes pride in his work.  He doesn't know yet, but he'll be getting a nice thank-you gift for helping me with this.  When the garage looked like this:

I was getting anxious.  I'm no stranger to working on mechanical things, working on cars or my boat, but an engine bay disassembled onto multiple tables was another level.

Putting things back together has been interesting.  It's amazing how hardened and brittle seals and gaskets can get (like I said, this deep of a dive is a first for me).  Here it is as it sits on the stand now:

Everything cleaned along the way.  Replaced necessary valve bucket shims (bucket shims... that wacky setup was a new one for me...).  New seals and gaskets everywhere.  OEM recommended threebond sealant.

And oh lord I should have bought Brakleen by the GALLON.  The chlorinated store brand stuff is 95% as effective and costs much less, but I should have invested in a reusable spray can and much more of the precious solvent.

Providing I can get the intake reassembled this week, this Friday we hope to get everything back in.  Then comes the oil system priming and hopefully a successful start.

More to come...

[subisubisu]

Nice!  Sorry for the reason, but it will be so good to have the new beating heart in your car's chest.  Keep going!

[SilentJ20]

Well, this is a quick resolution.

Engine back in!

Took a full 5qt of oil to fill it, as it was bone dry other than whatever was used during assembly.  Coolant added/burped really easy, no overheating.

The sti clutch, pressure plate and flywheel (oem Exedy brand, nothing fancy) will take some getting used to, as now the engage point is deeper into the pedal.  I need to take it easy for a few tanks and do lots of stop/go city stuff to help it bed in before I really mash the skinny pedal.

It's taken 6 weeks and at least a half dozen good chunks of work, but it saved so much money and was a great time hanging out with a good friend.  But it's essentially a new engine ready for another 139k miles.

[SilentJ20]

Just a quick update:

I'm 500 miles into the break-in procedure. According to Exedy, the clutch is now considered 'broken in'.  But the rest of the engine will still be treated carefully (ie, no full boost and redline).  I've basically gradually increased to "normal" driving.  Mild boost, engine breaking during deceleration, not holding constant rpm for long times.  By my estimates, the engine has already rotated around 2 million times throughout various road conditions.  Not sure what another 2 million will do, but I'll slowly work into more serious conditions.

As for car health I have no leaks anywhere.  The oil is clean and coolant is green.  Haven't pulled a LearningView yet since until recently I've been babying it and it wouldn't be accurate.  But now that I'm driving more normal I'll pull one soon.  Hopefully nothing else major rears its head for some time.

[Febreze Mee]

Def going to recommend UOAs. Blackstone has a great kit to monitor the internal health. 

[SilentJ20]

Just an update to those who may be following.  Coming up on 1000 miles since first start, and the Learning View looks fantastic (screenshot from BtSsm):

Perfect IAM, zero knock events and the fuel correction % are less than 5% which is ideal.

Still haven't pushed too much above half-throttle/low boost.  But the LV doesn't reflect much open-loop data anyways (none, as far as I'm aware).

Had a small external coolant leak (turbo coolant hose) because of an old spring clamp.  Replaced it with a regular hose clamp and seems to be gone.

Edited August 24, 2023 by SilentJ20

[Max Capacity]

FWIW, we did a street tune on my wagon with 500 on the ej257. Your safe for WOT. Enjoy the fruits of your labor and money...

[SilentJ20]

18 minutes ago, Max Capacity said:

FWIW, we did a street tune on my wagon with 500 on the ej257. Your safe for WOT. Enjoy the fruits of your labor and money...

I figured I was probably safe for it.  Not much will change in the engine with another couple hundred miles.  I bet 95% of "break in" was done after a couple hundred.  But I think I'm trying to train myself to not flog the car, haha.  I know it's not exactly fragile, but I want to make sure I get into a habit of less 'racecar' and more 'daily driver with zip'.

[Max Capacity]

My thought is, it's ok to drive it hard, just make sure you give it time to cool off, before shutting off the engine. I always made a point to try and coast as far is I could before shutting it off.  Think of coasting on the off ramp after you've been driving on the highway. Your mostly like going to have to stop at the end anyway. Even before getting home, just drive easy as you near home, coast if you can.

[SilentJ20]

10 hours ago, Max Capacity said:

My thought is, it's ok to drive it hard, just make sure you give it time to cool off, before shutting off the engine. I always made a point to try and coast as far is I could before shutting it off.  Think of coasting on the off ramp after you've been driving on the highway. Your mostly like going to have to stop at the end anyway. Even before getting home, just drive easy as you near home, coast if you can.

Good advice, and thankfully I'm already in the habit.  My previous car was a Saab 9-3 with the GM 2.0T that I learned about letting things cool down.  Paranoia and first turbocharged engine made me learn a lot.