99 outback to 98 forester ej25 engine swap issues

[Tetonvalleynick]

I put the engine from a wrecked 99 outback into a nice 98 forester that threw a rod.

 

Things were going mostly okay until I went to connect wire harnesses and I noticed that they didn't match.  I then looked the intake manifolds and they were slightly different so I wouldn't be able just swap the manifolds and wiring harness over.  I didn't check every connection, but it seemed that most of the connections from the two manifolds were the same, but the bolts on the manifold from the 98 forester were offset while the bolts on the manifold from the outback were all in a straight line.

 

forester engine intake

 

outback engine intake

 

 

Is it possible to get this outback engine to work with the forester?  If so what do I need to do?

[AdventureSubaru]

Post pics of the motors themselves. It's one of 2 things - Either we are looking at a Phase 1 EJ22 in the forester or a phase 2 EJ25. Phase 1s are compatible and phase 2 are not.

 

I suspect that it's phase 2 as all phase 1 motors would have matching wiring harnesses.

[Tetonvalleynick]

It sounds like you are saying that the ej25 in the outback is a phase 1 and the forester has a phase 2, is that correct?

 

They are both ej25's

 

Here's the forester:

 

 

Here's the outback:

 

[idosubaru]

That's a 1999 Forester engine - not a 1998.  So it's Phase II and not compatible. 

 

Easiest solution is to bolt the Forester heads to the outback block, then you retain all the Phase II manifold/electronics. 

And you get to resurface the heads and install new headgaskets.

 

Installing a Phase I engine into a Phase II vehicle is not simple.The idle bypass controllers are significantly difference and not easily dealt with.

Prop the throttle open, work the gas pedal as needed and hope for no check engine lights or ignore them. 

[wtdash]

HI,

Look on the Forester's VIN plate by the driver's side strut tower. It'll indicate  the original engine....looks like the attached. And the Forester is a SOHC 2.5; OB is DOHC 2.5. Unfortunately, the'99 model year had some transitions that weren't applied to all models:

Edited February 26, 2016 by wtdash

[idosubaru]

I don't think he needs the VIN plate - it's a SOHC EJ25 engine

counting cams or looking to see if the plugs insert straight in or at an angle are dead give aways.

 

Phase I DOHC EJ25: 1997-1999 Outback and 1998 Forester

Phase II SOHC EJ25: 1999 Forester and 2000+ Forester and Outback

Edited February 26, 2016 by grossgary

[AdventureSubaru]

Yep. you're trying to put a phase 1 engine in place of a phase 2. As mentioned, the blocks are the same so you can put the forester heads on the outback block and make a good motor.

 

Or shop for a different motor. 2000-2002 legacy and outback, 1999-02 Forester and Impreza (Imprezas will mostly be single port EJ22s but bolt in just fine other than getting the Y pipe from the impreza.

[Tetonvalleynick]

Thanks for the information.  

 

I'll pull the heads off and have them checked.  The previous owner ran it out of oil so I'll cross my fingers.

 

So if the heads are are okay, is there anything else I will have to do?

 

The forester was made 7/98 and the outback was made 10/98

 

go figure they have two different ej25's

 

EJ253AXZVB in the forester and

EJ25DAWEYL in the outback

[Tetonvalleynick]

AdventureSubaru, thanks for the posting the models years that work with this.

I'll go ahead and look for a new engine while I wait to find out if those heads are okay or not, so if they are I will be able to order it right away.

[Tetonvalleynick]

When getting a head gasket kit for this I would use the the 99 forester SOHC engine to look it up right?

[AdventureSubaru]

Yep. for this style of gasket make sure to have the heads machined.

[Tetonvalleynick]

Okay everything went together fine.

 

The engine runs when I start it, but it sounds like it's knocking.  The block never had knock or piston slap with the other heads on it.  That doesn't seem like something that would manifest itself with different heads on it, but if it is, I am sure someone here would know.

[86BRATMAN]

What head gaskets did you use?

[Tetonvalleynick]

6 star head gaskets

[Fairtax4me]

You put the 253 block between the DOHC heads?

The 253 blocks are known for having piston slap.

Make sure the timing belt tensioner isn't bouncing around. Those are easy to damage when re-compressing the piston.

[86BRATMAN]

It sounds to me like you used the ej25d shortblock, with the sohc ej25 heads and sohc ej25 head gaskets correct? If that is the case there is a very high likelihood that the noise you are hearing is piston and head contact. You cannot use phase 2 head gaskets on a block with phase 1 pistons in it because they protrude above the deck surface.

[Tetonvalleynick]

fairtax4me, it was the other way around, 25D block between the phase II heads

 

86BRATMAN, so the pistons are coming in contact with the head gaskets?

[86BRATMAN]

More than likely that's what is going on. You have pistons that poke out of the block about 0.5mm, and a gasket that is roughly the same thickness when compressed.

[Tetonvalleynick]

So the phase I head gasket is slightly thicker?

 

Basically I have to take the engine back apart and put phase I head gaskets on it because they are thicker when compressed?

 

Are the pistons or heads damaged from running it like that?

[Fairtax4me]

Ahh I gotcha. 

Like Bratman said. The pistons crest above the top of the block deck on the 25D. Have to order thicker head gaskets or use the 25D gaskets. 

[Tetonvalleynick]

Should I worry about having done any head or valve damage?

[Fairtax4me]

Yes, the phase 1 gaskets are slightly thicker to accommodate for the piston height. 

I wouldn't worry about it too much. Its basically a light tap, and they're probably only touching on the exhaust stroke when there's no load on the piston or bearings. 

Valves are closed when the piston is at the top of the stroke so no worry there.