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Old 02-19-2018, 01:51 PM   #26
Hotsho111
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lpxltt thanks. I'm on the west coast at the moment

I think I'm gonna pull the intake and headers to examine the cylinder more closely. At that point, most of the work is done so if I do need to swap the shortblock I'll probably have a shop do the swap itself because I don't have the space and then I can put it back together
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Old 02-20-2018, 03:37 AM   #27
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Quote:
Originally Posted by Hotsho111 View Post
Budget isn't an issue, although I don't really want to buy a new car because I'm trying to save for a house.
I'm going to stop you right now.

Before I became a Subaru mechanic, I sold real estate. If you're thinking about buying a house in the next year or two, DO NOT buy a new (to you) car. $300/mo on a car is $300/mo less house you can buy. $300/mo makes a significant difference in the amount of house you can afford.

Ok back to your thread.
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Old 02-20-2018, 03:48 AM   #28
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Oh for the love of god stop running it. I'm going to 2nd that the electrode is still in the cylinder, and it sounds like it's just pounding around in there. If that's the case, you run the risk of it getting stuck in the exhaust valve, keeping the valve open, and if that happens it's valve to piston contact time.

I firmly believe you already need to replace that piston. Even if the ring land hasn't been squashed, it's got a lot of dents on it. I'm no combustion engineer, but I'd wager that high spots would heat up and potentially lead to detonation. Plus the cylinder head is going to look just as bad, so I'm suggesting getting a new head. If the cylinder wall hasn't gotten scored, you might be able to get away with reusing the short block, minus that piston, but I'd recommend new bearings due to the impacts anyway.
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Old 02-21-2018, 01:00 AM   #29
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I appreciate the feedback Cosmo but I'm well aware that buying a new car isn't an ideal option in this situation.

I called one shop who estimated 6k on the low end and 10k on the high end (new heads) to fix. I'm going to call a few other shops to get prices.

I'm currently planning on pulling the engine and taking it apart to get a good inspection of what's wrong. If the cylinder is toast but the headers are ok I'm probably going to buy a new shortblock, have the heads rebuilt, and rebuild it. If the cylinder and headers are toast I'm going to buy a rebuilt longblock and install it.

I've found rebuilt longblocks from sunwest auto and atk. Anyone have other good sources to check out for longblocks?

ETA: I'm going to price out the costs of a shortblock rebuild and longblock rebuild as well to see how much either would cost

Last edited by Hotsho111; 02-21-2018 at 01:11 AM.
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Old 02-21-2018, 07:22 AM   #30
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I have bought a 2.2 NA and a 2.5 NA from the old CCR near Denver. A few years ago they had issues but that was partly due to health issues with the owners.
About 2 years ago, the business changed hands, have not heard much since then.

Note, CCR is Colorado Component Rebuilders and all they did was Subaru engines.
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Old 02-21-2018, 10:21 PM   #31
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Thanks for the info Charlie. Unfortunately it looks like they've shot down.

I called a few other shops for some quotes and I'm going to price out the parts cost this weekend and I'll go from there

Thanks for the help so far everyone!
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Old 02-24-2018, 08:44 PM   #32
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I'm having some trouble finding the right information, but what are the recommended things to place when replacing a shortblock (besides the obvious stuff)?

I'm planning for: oil pump, oil pickup, thermostat, water pump, timing components, coolant hoses.

I'll check the fuel injectors and fuel lines. Anything else?

I'm planning on reusing the oil pan, cam sprockets and crank sprockets

I might replace the clutch while it's out too although I haven't had issues with that

There's obviously a bunch of seals...so many seals
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Old 02-26-2018, 12:12 AM   #33
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If metal went through the oil pump, sure. If not, I wouldn't worry about it. They don't really go bad unless metal goes through them or oil doesn't.

Just get the OE engine set. You'll end up with extra stuff, but you'll get everything you need. Except maybe exhaust gaskets. Or was it intake? Anyway, get the set and ask what it doesn't come with.
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Old 02-26-2018, 10:10 AM   #34
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Iĺl tell you my story (hopefully it helps)

So I had bought my 2005 subaru impreza from Rafferty Subaru for around 8k with 92,000 miles (I know, horrible deal but whatever)

Turns out, 6 months later while driving home from work, I had noticed a knock like sound from my engine. After taking it to my mechanic, it turned out that my car had a bad rod bearing (basically rod knock)

After talking with SOA and the dealership for weeks, I had a 91K mileage engine replace my old engine ($2,500 for the engine + labor and wiring)

If I were you, I would buy the engine and have an independent shop swap the engine for you and wire it, if you still want to keep it.

I love subarus, but a lot of their cars are known to suffer from engine problems
Just my 2 cents, good luck!
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Old 02-26-2018, 06:28 PM   #35
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I would just go for a replacement engine.
No point in swapping heads over on a short block as the head will have been damaged by the looks of the piston.
Find a place selling engines with something like a 3 month warranty if you can.
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Old 03-03-2018, 08:43 PM   #36
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I took a closer look at the oil I removed and it looks like there are small metal flakes in there so if I do replace the shortblock I'll probably replace the oil pump to be safe

I've priced out all the parts and stuff I need and it's a little over 2400 (new shortblock, oil pump, oil pickup, thermostat, timing kit, gaskets, seals, sealant, and orings). I'll probably replace the coolant hoses while I'm at it so add another 50 or so. I'll do the clutch with the engine out too

I got the same machine shop recommendation from the local subaru specialty shop and one other shop so I've been chatting with and they are gonna check out and rebuild the heads for 200-400 (depending on damage). So, for 2600-3000 I'd have a mostly new engine.

@Chris, I feel like that's an awful lot for a used engine. I was looking up local used engines and LKQ had engines for ~1400. I've found rebuilt longblocks for 2500. Even still, I'd rather have a mostly new engine since I'll probably keep the car for a while.

I've got everything unhooked to pull the engine except the starter, motor mounts, and bell housing. I'm waiting for my buddies hoist before I do that though.

The previous owner did some weird things to the car and I know they had an oil pressure gauge installed (which I now know is leaking...) and noticed they removed the old oil sensor and left the cable for it unhooked. I get the red oil light when I start up the car but it goes off shortly after that and I'm not quite sure why.
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Old 03-14-2018, 11:45 PM   #37
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Got the engine out and took the head off. Confirmed the spark plug tip was what was making a racket. It was still in the cylinder. The piston has a bunch of dents in it as does the cylinder head:
The culprit


Damage to the piston (the cylinder actually looks ok). You can see the damage on the bottom side of the piston


Damage to the cylinder head (I wiped the area down before taking this picture). That chunk of metal was stuck in the cylinder head.
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Old 03-15-2018, 03:01 AM   #38
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If it was my car, I'd probably pull that piston and check the rings for any pinched spots, then smooth out the roughness in the head and throw it back together (maybe new piston if needed) and send it. I bet it would be fine.

If I were working on a friend's car, I'd present it as an option.

In a professional shop, my recommendation might be a little different (when you're paying a buddy in food and drinks, or a couple hundred to hook you up, it's vastly different than gambling with a nearly $2000 bill).
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Old 03-15-2018, 11:03 AM   #39
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Quote:
Originally Posted by CosmoTheCat View Post
If it was my car, I'd probably pull that piston and check the rings for any pinched spots, then smooth out the roughness in the head and throw it back together (maybe new piston if needed) and send it. I bet it would be fine.

If I were working on a friend's car, I'd present it as an option.

In a professional shop, my recommendation might be a little different (when you're paying a buddy in food and drinks, or a couple hundred to hook you up, it's vastly different than gambling with a nearly $2000 bill).
Totally agree. Decent bet is to smooth off the rough spots (they can promote detonation) on the head and piston.
Pull a piston to check for pinched rings? Sorta coin toss. Easier now, question do you do it now?
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Old 03-16-2018, 12:04 AM   #40
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Thanks guys, that's definitely one option on the table.

Some good news, the other head is in good shape and I bottomed out the #2 cylinder and the cylinder itself isn't damaged.

I was planning on taking the heads to a machine shop to be rebuilt anyway so it's a matter of if I want to split the block and have them clean and hone it as well or just replace the pistons.

Unfortunately, I did shear the two bolts that hold in the metal coolant return pipe that goes to the water pump
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Old 03-18-2018, 11:22 PM   #41
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The carbon buildup seems normal
Im guessing the broken piece of the plug is stuck in the aluminum of the cylinder head.
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Old 03-18-2018, 11:24 PM   #42
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Oops, I did not see the second page and pictures !
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Old 03-19-2018, 12:39 AM   #43
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Hoping to get everything over to the machine shop this week.

One of the cylinder head bolts had a small amount of rust on it:


I was planning on reusing the bolts but should I replace that bolt or would it be fine to retap it and clean the threads? I was planning on doing the same for the cylinder hole that was in.

Is there any issue mixing old and new bolts? Would I just need to do the stretch portion of the install for that one bolt?

I sent ngk an email too since the spark plugs were only 2.5 years old and had done ~12k miles
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Old 03-19-2018, 08:09 AM   #44
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I would wire brush that bolt and then use it.
Do the oil dip and full torque sequence as per the manual.
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Old 03-20-2018, 03:58 AM   #45
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Yup. Wire wheel it and run with it.

IIRC those are M11x1.25, not a common tap/die size at all. I run all head bolts through a die to pop grit out and smooth any dings, but that's just me.
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Old 03-20-2018, 10:53 PM   #46
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Sounds good, thanks guys. I was planning on doing exactly that Cosmo

Got all the parts ordered so I'll be dropping the heads and block off at the machine shop in a week or so

Still haven't heard back from NGK so I'm probably going to call them sometime this week
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Old 03-26-2018, 07:15 PM   #47
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Go get a Jdm low miles motor. They are reasonably cheap and usually come with a 2 month warranty.
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Old 03-26-2018, 10:00 PM   #48
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I definitely thought along those lines (STi swap!) but that's a can of worms I don't particularly want to deal with and I can't imagine CA would be too thrilled with a JDM motor.

All the parts are in and I'm dropping it off at the machine shop in the morning
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Old 04-22-2018, 03:19 PM   #49
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Finally got everything back from the shop. I ended up with 4 slightly bent valves from that cylinder. Since it was already disassembled I asked them to tear down the block too and they said one of the journals was starting to wear a bit. They estimated it would have lasted another 30k miles but would have become an issue so that at least paid off. Beyond that, everything was good.

I'm not sure if they dipped everything versus just cleaning the necessary surfaces though as the outside surfaces aren't as clean as I would have expected.

I wrote a lengthy rebuild checklist (~135 steps!) and I'm planning on rebuilding it next weekend.

Shop costs ended up a lot higher than I was expecting and came out to $1300. All in all (including all the little bits and bobs), I'm looking at $2700 all said and done but that's including a lot of "while I'm there midaswell replace it" parts.
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Old 04-22-2018, 06:12 PM   #50
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Still haven't heard back from NGK so I'm probably going to call them sometime this week
I suspect you never got any love from NGK?
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