subaru FB25 engine interchange

Great info!

Did you use factory of aftermarket gaskets/O-rings and what sealant(s) where?

I bought a good quality gasket set from RockAuto.  It included all gaskets, O rings, and Felpro head gaskets.  I replaced all O rings - coolant crossover pipe, upper oil pan, front timing cover.  I used Permatex black on upper oil pan, oil pan, cam carriers, front timing cover.

The coolant pipe from water pump to heater hose was rusty so I put rusty metal primer and rustoleum black on it.  After running for a while, the pipe got a pin hole leak.  $65 from Subaru for a new pipe and somewhat of a pain to put on after engine is in the car.  I just took the car for another drive and all seems good.

It will take a few shakedown runs to get all the bugs out of this.  I have no history on either engine or the car itself - so I am sure there are gremlins waiting to make themselves known.

Thanks to all the folks here on GRM that have pioneered and contributed to this swap! I'm planning to do this myself shortly on my wife's 2011 Forester with 130k miles. It burns a quart every 500 miles so I feel it's about time to do this.

I'm, going to summarize what I've understood from the whole thread, please comment and correct me if I'm wrong here. Hoping to reduce the number of times me or future readers has to scan the entire thread to double check information:

Swap checklist for 2011/2012/2013 Forester

2013-2014 Legacy and 2014-2015 Forester engine swap:

1. Swap Valve Cover to 2011 spec
2. Swap coils to 2011 spec
3. Swap coolant crossover pipe to 2011 spec
4. Swap EGR tube to 2011 spec
5. Swap torque converter  and flex plate to 2011 spec (try to leave torque converter on transmission)
6. Swap sensors to 2011 spec
7. Swap engine mounts to 2011 spec

2015-2019 Legacy and 2016-2018 Forester engine swap:

1. Swap Valve Cover to 2011 spec
2. Swap front cover to 2011 spec
3. Swap cam tone wheel to 2011 spec
4. Swap coils to 2011 spec
5. Swap coolant crossover pipe to 2011 spec
6. Swap EGR tube to 2011 spec
7. Swap torque converter  and flex plate to 2011 spec (try to leave torque converter on transmission)
8. Swap sensors to 2011 spec
9. Swap engine mounts to 2011 spec
10. Plug lower oil pan coolant hose or swap to 2011 spec upper and lower oil pan
11. Use newer 2015+ intake along with 2011 TGV magnets and activators along with 2015+ gears and 3mm spacers, with pins 4 and 5 flipped on the connector.
    1. See CHayNZ thread for clocking specifics

* Swap out as many gaskets and hoses as you can while you are here like throttle body hoses, spark plug tube gasket, rear main seal, front cover o-rings etc. Get injectors cleaned and tested.

** For the 2015+ swap, if purchasing the idler bracket and intake adapter from Creative CNC (Joe?) you can forego using the 2011 timing cover and the 2015+ intake and TGV changes as mentioned in step 11 but need to extend your EGR tube by 15mm. (Didn't see the intake adapter on the site so maybe they are not selling those anymore?)

*** VVT should be the same across all FB25B engines due to AVCS (someone please correct me here if I'm wrong).

My first post here. The detailed information you all have provided to make this thread inspired me to try and save a 2013 Forester whose motor blew at 160K. So I’m in the process of dropping in a donor 2017 Legacy FB25 with 64K, having done the recommended mods:  timing cover and cam reluctor plate swap, wire harness and sensors, water crossover, flex plate and crankshaft reluctor plate and sensor, shimming coils. (I decided to keep the 2017 intake manifold, and modified the tgv valves leaning heavily on the work of Skenton, Sodapopdave, and ChayNZ. The tgv mods tested successfully on the bench per multimeter. I’ll contribute a few pics of my process if things turn out right, and folks want more visual input on the subject.)

The work has gone well, and I’ve been having fun, but think I have hit a wall.

When I bolted up (with a little more difficulty then seemed reasonable) the engine to the transmission, I was unable to turn over the engine by hand to line up flex plate and torque converter. The bolt on the balancer wheel just got tighter. Figured the torque converter must have moved when I pulled the old engine causing things to seize, so I took out the donor engine to fix things. Torque converter started to come out too, but I separated it from engine before fluid spilled. With engine out, I reseated the torque converter per instructions reposted in this thread and reinstalled engine. Still seized. Now I’ve removed engine a second time, this time torque converter stayed in place by a fastener tie.

Going over things carefully, I noticed the alignment bushing on the crankshaft didn’t seem right — too shallow, and not concave at the bottom like on the 2013. The donor 2017 measured ~7/16” from top of bushing to bottom. The 2013 measured ~1-1/6”, top to bottom. It almost seems like the alignment stud on the old torque converter broke off in the donor engine? But before I start drilling EZ Out holes, was hoping someone could confirm the proper depth of the pilot hole on the 2017 crankshaft flywheel.

Appreciate your help.

2017 Legacy donor

The bottom of the bushing is not concave, but flat. Broken guide stud?

2013 Forester "old engine"

Looks for all the world like the end of a torque converter is still in the engine.  I've never seen that happen, but there is always a first time.

In reply to Pete. (l33t FS) :

Thanks for responding.

Me and unique problems. Seems the only explanation though, doesn't it.. I'll try extracting today, time allowing. If I understand the torque converter / flywheel bushing relationship correctly, the bushing is there to align TC to engine, and the bushing depth (now restricted by a broken stud) allows some expansion/contraction space for movement between components caused by temp changes, vibration, etc. 

First post... this thread has been very helpful in my 2015 Legacy engine swap into my daughter in law's 2012 Forester.  Thanks for all contributors!

Question - I've read through most of the content but couldn't find anything related to swapping out the fuel injectors.  Can I leave the 2015 injectors in place?  Thanks!

In reply to shiskowd :

I went with the younger injectors that came with the 2017 Legacy donor engine. They are working well so far in the 2013 Forester. No codes.

I've done this swap 3 times on the same vehicle. 2013 Forester X. The first engine was knocking right off the bat. I decided to get another engine and installed a brand new Subaru front cover on it for the 2013 model year. It started knocking after 3000 miles. Got another engine with 46,000 miles on it and I'm getting the knocking issue again. I changed the oil and when I went to replace the filter after draining the oil, the filter had not drained back into the engine like it should have. Is there something I am missing?

In reply to Frustrated1 :

I do this swap at least once per week, just literally "found" this thread/forum (small 1 man subaru shop) Are you priming the engine before startup? With a new front cover/oil pump. Thats all I can think of honestly

Frustrated1 said:

I've done this swap 3 times on the same vehicle. 2013 Forester X. The first engine was knocking right off the bat. I decided to get another engine and installed a brand new Subaru front cover on it for the 2013 model year. It started knocking after 3000 miles. Got another engine with 46,000 miles on it and I'm getting the knocking issue again. I changed the oil and when I went to replace the filter after draining the oil, the filter had not drained back into the engine like it should have. Is there something I am missing?

The filter should not drain back.  There is supposed to be an anti drainback valve in the filter to prevent it.  SOP when doing an oil change is to punch a hole in the filter first, do all the other services, then change the filter last so it doesn't make a huge mess.

Hey all, Just found this Thread, became a forum user now. I have been doing the FB swap forever, (small Suby 1 man shop). I mainly do Foresters...I want to start grabbing the 2017 motors now, been using the 14-16 engines w/ the normal recipe and always perfect. Major difference I am seing eyeballing Ebay pics/etc....is the EGR, what am I in for here? I always just use the original intake/tgv/harness/front cover etc....I do notice the egr though being different for the entry into bottom of the RH head. Thanks for any tips! Got 2 under the knife, would love to grab some 17' motors

Hi folks. Currently doing the swap right now and ran into some issues swapping over the tone wheels. It looks like the snap ring is not 100% snug on the groove once I swapped the left hand side. There's a slight gap, but it's not falling off. Would this cause issues? It's not coming off at rest but I'm not sure what happens when the cams are spinning if this will be at risk of coming off or throwing off the balance. The other side which I haven't removed is on there snug with no gaps as a snap ring normally is.

Subaru dealer says they do not sell the snap rings by themselsves but instead the whole cam sprocket...