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Spliting EJ25 block...

1949 Views 8 Replies 5 Participants Last post by  HOK
can anyone provide me the steps on spliting the EJ25 block...? with the procedures and first things or order of things to do?
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8 got any pictures??
Are you changing rods or the crank? If you are just replacing pistons you don't need to split the block.
call matt @tri tuning...he has done MANY!!!
just spliting it for educational purposes... hehehe....
You will need to remove the pistons and/or wrist pins first otherwise you'll only get it a few inches apart before the pistons bottom out in their cylinders. There are 4 access holes (2 on the front, 2 on the rear) of the block that are 14mm allen bolts (set screws?). Then you'll need the wrist pin removal tool from Subaru to get them out.

I believe there are bolts along the top and bottom seams of the block, those are apparent, then there ae bolts in the coolant channels around the cylinders, I think 6, but it might be 8.

Actually splitting it after all that is done... I'm not sure. I've never actually done it myself. I think you'll need to rap on it a bit with a mallet and pry it a bit, but I think overall it'll take a lot of effort. I've got a buddy with w VW block that just won't split... I can only predict how a decently-worn scooby block does.

Good luck, though. :)
i split the block... darn 8complex your experience came too late... hehehe the pistons bottomed out in the cylinders... so i put it back together... and was thinking of getting the wrist pin tool but the car has been misfiring at low rpm.. :( dun know why, gonna work on that now...

but there was a neat sound of compressed air when i removed the block bolts...psssssssssssssssshh

Well, if you seperate it an inch or two, you might be able to get the nuts off of the rod bolts and seperate the bottom end that way. I wouldn't suggest it because it'll probably never go back the same way since the bearings will more then likely drop out and you won't know what came from where... but you could do it if it's just an experiment. :)

BTW, you're working on a seperate engine then the one that has been misfiring out of your car, right? Just FYI, I believe there is seals and stuff that is inbetween the block halves that I would suggest replacing when splitting and resealing the block together.
heheh no no... my car is misfiring... this engine has been laying around for a year... i wanted to take out the cracked piston but decided to study the whole thing and maybe clean it up and inspect for more damage..

I started taking the rod bolts out but its too easy to strip them the way i'm doing it will a little 12mm wrench... so i stopped that...

if i'm going to use the block i'm going to send it to australia to rebuild.. so i won't do anything to it hehe.. they'll just have to get it in peices... :p
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