Rebuild it or replace it?

[98legacygt22]

Ok so I picked up a 1998 Legacy GT wagon the other day for $500 (needs head gaskets) because the body is cleaner than my 97 LGT wagon. It has the original 2.5 in it but I can hear what sounds like a rod knock. My brothers impreza had piston slap and it sounds nothing like that. I know some of you will say toss a 2.2 in there but no thanks, I like the power of a 2.5.

So should I order a master rebuild kit or save up a grand and get a low mile jdm import EJ25D? I've found rebuild kits for 5-600 and that comes with every gasket, pistons, bearings etc. If its just a slight rod knock I wonder if I can just have the rods and crank polished so I can put in new bearings and run it.

[EJ22D]

Ok so I picked up a 1998 Legacy GT wagon the other day for $500 (needs head gaskets) because the body is cleaner than my 97 LGT wagon. It has the original 2.5 in it but I can hear what sounds like a rod knock. My brothers impreza had piston slap and it sounds nothing like that. I know some of you will say toss a 2.2 in there but no thanks, I like the power of a 2.5.

So should I order a master rebuild kit or save up a grand and get a low mile jdm import EJ25D? I've found rebuild kits for 5-600 and that comes with every gasket, pistons, bearings etc. If its just a slight rod knock I wonder if I can just have the rods and crank polished so I can put in new bearings and run it.

If you're into rebuilding it, just know that more than just the rods & crank have been affected. The pistons would probably be a little weaker from the constant overheating & the heads could be warped. So rods, crank, pistons, & heads would need a little TLC in the rebuild department.

We all know that the rod knock is caused by the leaky head gaskets so replace it w/the JDM variant & do the head gaskets on that just to be on the good side of things. JDM 25Ds tend to keep kicking ass after head gasket replacement. Not to mention that you can keep your stock engine as a rebuild project while you rock on w/the JDM 25D. Your call.

[98legacygt22]

Ok so I picked up a 1998 Legacy GT wagon the other day for $500 (needs head gaskets) because the body is cleaner than my 97 LGT wagon. It has the original 2.5 in it but I can hear what sounds like a rod knock. My brothers impreza had piston slap and it sounds nothing like that. I know some of you will say toss a 2.2 in there but no thanks, I like the power of a 2.5.

So should I order a master rebuild kit or save up a grand and get a low mile jdm import EJ25D? I've found rebuild kits for 5-600 and that comes with every gasket, pistons, bearings etc. If its just a slight rod knock I wonder if I can just have the rods and crank polished so I can put in new bearings and run it.

If you're into rebuilding it, just know that more than just the rods & crank have been affected. The pistons would probably be a little weaker from the constant overheating & the heads could be warped. So rods, crank, pistons, & heads would need a little TLC in the rebuild department.

We all know that the rod knock is caused by the leaky head gaskets so replace it w/the JDM variant & do the head gaskets on that just to be on the good side of things. JDM 25Ds tend to keep kicking ass after head gasket replacement. Not to mention that you can keep your stock engine as a rebuild project while you rock on w/the JDM 25D. Your call.


It was taken off the road the day it overheated the first time. It's the beginning to a rod knock (the untrained ear wouldn't be able to even notice it) so yeah Ill check everything but I doubt it hurt the pistons at all. I have a low mile set of 25D heads from a 98 Forester that I'll slap on instead of the 194,xxx mile ones that are on it. I do like the idea of the JDM low mile motor though.

[Dead91silvia]

Possible solutions...

New/used bottom end - machine old heads and install

complete used motor

I wouldnt do a rebuild, but thats me... I have an EJ25D in my BD with 283K miles and she's still running. I got the current motor with 250K and a burned valve. My old motor spun a bearing and I just saved the heads. I blew a HG about 12K ago, but it was the one I didnt replace at the time.

I'm with you on the 2.5, despite people saying they are weak and unreliable, I have no problem with mine and will run it till it has catastrophic failure such as parts flying. At that time, it will get a swap of some kind if the funds are around.

[EJ22D]

I'd use the bottom end if it only overheated once because I know that's not nearly enough to consider it compromised.
The rods & crank would need a little work but the bearings are really the big issue here. Replace those & that engine will keep on going. Another thing to consider is down time. How soon do you need to drive that GT? If not very soon, then you pretty much have time to do the bearing replacement & recondition the heads.

As for Dead91Silvia's comment on the 25D being tough, he's right on the money. They only become weak when they are soldiered on without any kind of repair to the head gaskets. As for "catastrophic"...
https://sl-i.net/FORUM/images/imported/2012/11/IMG2011102000077-1.jpg
...I drove mine until I popped a rod out of the block & still had to keep going an extra few miles to avoid the tow! LOL! The EJ series are tough little engines. You just have to treat them right.

[98legacygt22]

That's the reason why you built the 22D right? I probably will just take it apart, clean the block and buy new bearings. You can barely hear the noise but I don't need to drive it right away. I've been borrowing a 98 Outback. Do you think I could re use my crank and rods or are they toast in your guys opinion? I would buy another short block but who knows how long that replacement will last. I'm up in the air about it, I still have to find an engine hoist too.

[EJ22D]

That's the reason why you built the 22D right? I probably will just take it apart, clean the block and buy new bearings. You can barely hear the noise but I don't need to drive it right away. I've been borrowing a 98 Outback. Do you think I could re use my crank and rods or are they toast in your guys opinion? I would buy another short block but who knows how long that replacement will last. I'm up in the air about it, I still have to find an engine hoist too.

Yeah, I'd have probably gotten a 251 block but didn't have $500+ the time.
When I got mine, I had a small knock too but from July to about Sept, it got a LOT louder & blew up in Oct of '11.
20w-30 kept me going for quite a bit! As for your crank & rods, there is really no way to tell what condition they're in until you see them but even after blowing up, my crank (I opened the block) did not have too much damage & could have been re-cut to reuse but I didn't have that kind of time (I wanted to do 2.3L!).
I'd say crank & rods are not toast, just the bearings but limit the amount of times you start it to preserve what's left until the teardown day. If you're going to buy another shortblock, get a Phase 2 2.5 (251/253). They're pretty damn tough.

[Barbbachello]

If you really dont need to drive it for a while and have some money you could do a turbo swap from a WRX or STi

[98legacygt22]

If you really dont need to drive it for a while and have some money you could do a turbo swap from a WRX or STi

Yeah I just gave up on one of those projects :grin: N/A it is for me

[98legacygt22]

That's the reason why you built the 22D right? I probably will just take it apart, clean the block and buy new bearings. You can barely hear the noise but I don't need to drive it right away. I've been borrowing a 98 Outback. Do you think I could re use my crank and rods or are they toast in your guys opinion? I would buy another short block but who knows how long that replacement will last. I'm up in the air about it, I still have to find an engine hoist too.

Yeah, I'd have probably gotten a 251 block but didn't have $500+ the time.
When I got mine, I had a small knock too but from July to about Sept, it got a LOT louder & blew up in Oct of '11.
20w-30 kept me going for quite a bit! As for your crank & rods, there is really no way to tell what condition they're in until you see them but even after blowing up, my crank (I opened the block) did not have too much damage & could have been re-cut to reuse but I didn't have that kind of time (I wanted to do 2.3L!).
I'd say crank & rods are not toast, just the bearings but limit the amount of times you start it to preserve what's left until the teardown day. If you're going to buy another shortblock, get a Phase 2 2.5 (251/253). They're pretty damn tough.

Yeah I was thinking about an ej251 short block and phase 1 22E heads and just run it like that. I will keep the car shut off until I pull it into the garage to pull the engine/trans out (also going to be swapping to 5 speed)

[harrymaneuvers]

By phase 1 2.2l heads do you mean dual port like what came on the ej22t? From my research, you would also need the intake, wiring, ecu ect to make it work. Not really easy or quick.

[98legacygt22]

By phase 1 2.2l heads do you mean dual port like what came on the ej22t? From my research, you would also need the intake, wiring, ecu ect to make it work. Not really easy or quick.

No :grin: I'm talking about the regular dual port ej22e heads. Some think all the phase 1 2.2 heads had single port exhaust but that's not actually true.

[harrymaneuvers]

I think you have that backwards. Someone correct me if I'm wrong but all ej22 heads from 96 to current are single port exhaust which some claim dont flow as well as the ej22 heads from 90-94 which are dual port exhaust.

[EJ22D]

I think you have that backwards. Someone correct me if I'm wrong but all ej22 heads from 96 to current are single port exhaust which some claim dont flow as well as the ej22 heads from 90-94 which are dual port exhaust.

In order of flow, it goes like this (from worst to best).
91-94 22T heads.
96-98 22E (SP) heads.
90-95 22E (DP) heads.
96 & 97-99 25D (DP) heads.

OP, if I were you, I'd stick w/25D heads & slap them on the 251 block & use 251 head gaskets. You'll have the power that you want & still be able to run 87 octane on the stock ECU. Using a Phase 2 block opens you up quite a bit to a little more reliability & interchangeability w/STi internals. :D The 22E/25D combo is nice & delivers nice low-end TQ but they do run pretty harsh (SOHC) & always need to be fed 91 or 93 octane. You cannot even get away w/89. Still, in terms of N/A, I do not think there is any N/A base Subaru EJ frankenstein out there better than the 22E head/25D block combo or the 97-99 25D head/96 25D block combo. They just need to have high octane as a sacrifice for that little bit of extra power.