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Nudnik 07-09-2011 04:48 PM

I'm rebuilding my motor. Any tips or ideas?
So my first (technically 2nd I guess) Subaru has been a challenge to say the least. In the month that I've owned it, she has only run approximately 8-10 days. After replacing the timing belt this week, I drove it to work w/no problems and then on the drive home the motor died. After towing it home/shop for the 4th time since I've owned it, I discovered that one of the pistons is completely destroyed, along with the head. Fortunately, the guy I bought the car from gave me the old motor that was in it so I could have some spare parts. I'm very grateful b/c now I'm going to rebuild that motor (which had blown main bearings) to put back in my car. All that being said, any tips or advice on the rebuild process. Any cheap upgrades that are considered a must? Any hints on rebuilding the motor that could prevent some headaches on my end? Thanks in advance & I'll keep you updated on the process.

psinuse 07-09-2011 08:06 PM

Hmmmm where to start.
1) First decided what you want to do with this motor<--that will dictate what parts to buy and in the end how much money your going to spend.
2) Check the price of a shortblock from Subaru. In all honesty if your not going to go all out then this would be a cheaper alternative to rebuilding the existing motor. Quicker as well because you'd had less downtime.
3) There are no cheap upgrades. Tips and tricks to getting it together yes, cheap not really.

Sorry to hear about this bad experience with this car and from the sounds of it the guy before you must have run the dog snot out of it and trashed it pretty good.

Nudnik 07-10-2011 12:52 AM

Rebuilding it stock. Not looking to upgrade or spend any significant amount of $$$$. Really just looking for tips on the rebuild.

As for the previous owner trashing it, he didn't trash it at all. Biggest problem was the fact that it was a used motor & I just ran into a shit storm of bad luck. It happens.

Anything on pullling the old motor or rebuilding the new motor that I should be on the look out for?

psinuse 07-10-2011 06:37 AM

I'd suggest getting a new shortblock from Subaru. When you add up the cost of machining, parts and labor it would be cheaper in the long run. You could sell the 2 current motors to help make up the cost of buying a new shortblock. Keep the good set of heads and just buy everything else new, oil pump, timing kit things like that.

As far as removal it's pretty straight forward, the hardest part will be separating the engine and bell housing, that just takes some force and usually 2 people. If your really wanting to rebuild it then I can make some suggestions, but it really is cheaper if your going stock to just buy the factory shortblock.

Sorry about assuming the previous owner trashed it, it's been my experience over the years that that is what happens more times than not.

wagonracer 07-10-2011 08:27 AM

Keith's advise makes the most sense, and you can save $$ by getting a rebuilt short block from [url=]Welcome Duners[/url] They also have a good price on the complete gasket and seal kit (which you'll need). I have one of their blocks in my car, 45K miles + two seasons of track abuse so far, and have used a couple more in cars I've rebuilt and sold. They use ACL race bearings and warranty them (one year, same as Subaru)

By the time you get the old block with spun bearings apart, find the damage, get the crank and rods machined or replaced, find over-sized bearing sets etc., you'll be in a ton of time and money.

Keep in mind that you'll also need to replace the oil cooler and pump, since it sounds like both blocks have metal in them. You can clean the pump out, but the cooler is pretty much impossible to get all the shrapnel out of. Also, make sure that your turbo doesn't have little bits of metal in it, too or it'll take out the new block.

Full shop manual can be found here [url=]Impreza Manuals |[/url] with all the instructions you'll need, including important stuff like torque specs, valve clearance etc.

Nudnik 07-11-2011 12:08 AM

Thanks for the advice but after examining the original motor & plastigauging all the bearings, I've decided to press my luck on Frankensteining a motor together out of the 2 that I have. There were no signs (at all) of metal in the motor w/the blown piston bearing so I think I will be okay. At least for a little while. Things certainly couldn't get any worse & with the run of bad luck that I've had, I'm hoping that kharma will give me a little good luck. Who knows, maybe this Frankenstein motor will last me 100,000 miles. ;-)

psinuse 07-11-2011 07:36 PM

Not to rain on your parade, but "frankenstening" a motor is a failure waiting to happen to be honest man. Which will put you in a worse spot than your in now. You might get lucky and it run for a long while, you may not. Have you checked the bores to make sure they are within spec? You are planning on honing them correct? Are you going to replace the bearings as well? I only ask these questions because these are things that need to be done before you even consider tearing down either motor.
In any case best of luck and if you need some advice please feel free to ask away.

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