club.liberty.asn.au

Hey guys
Recently my liberty spun a bearing
I was just wondering if anyone knows the common causes of spun bearings in turbo ej20's?
I hope anyone has had any experience in this issue

Cheers
Jake

Jake

From http://www.superstreetonline.com/how-to ... gine-tech/
(just one opinion on the net)

Q: Focusing on the EJ205, EJ255, and EJ257 engines, there's been a lot of debate on their strengths and weaknesses and how they were never designed to handle an elevated horsepower level. Is there a secret recipe that can better educate Subie owners on how to build their engines to increase horsepower output and longevity?

A: The EJ-series motors are good motors, and we would not call them "weak" per se. On a stock motor, the two primary weaknesses are the stock cast hypereutectic pistons and oiling to the rod bearings. The pistons (particularly on the EJ255 and EJ257) will crack if subjected to knock/detonation events. Obviously, with proper ECU tuning the engine can be kept away from the knock threshold, making the pistons not as much of an issue.

Oiling to the rod bearings is the other primary issue. We typically don't see very many problems with the EJ255 and EJ257 in this respect, but do see it more on the older EJ205. Fundamentally there isn't a big difference between the 2.0L and 2.5L motors in terms of the design of the oiling system but the EJ205 is at least 5 to 9 years old now and some have not been treated to regular maintenance with quality fluids. From the factory, the allowable range of bearing clearance is pretty broad and if you don't use quality synthetic oil and change it often it can lead to problems. The same can be said of any motor, so while not a strong point of the EJs, it should not be painted as a "bad motor" because of it.

We don't believe in "secret formulas," but rather common sense. In the case of making EJ motors last, it boils down to proper ECU tuning by a reputable tuner who clearly understands the logic of the ECU and its interaction with the engine, along with regular maintenance and using quality fluids in the car.

Iirc knock, in addition to destroying ring lands, can also break, hammer, spin bearings.

So regular oil changes with synthetic, and keeping knock under control are probably the key

Thanks both of you guy for your input!
So would you say stock rods and the oiling journals aren't up to scratch when it comes to modification?
And basic lack of maintenance and care are causes for bearing malfunction?

There are so much more on the North American websites regarding some Subaru issues so Googling subjects and looking for US based forums is a wise idea.
Try this thread.
http://forums.nasioc.com/forums/showthr ... ?t=2401576

It appears that the rod bearings on a Subaru EJ engine need to be cared for. They are a potential point of weakness.
I have read threads in US forums saying that Mobil1 was more prone to rod bearing failures than other oils.
I have read threads that recommend to use Shell Rotella T6 synthetic Diesel Engine Oil in the turbo Subaru engines.
You could Google "Bob Is The Oil Guy" for more input.

I do not subscribe to the Mobil1 theory, it may have just been the most commonly used synthetic at the time the failures commenced in the US.
Everyone eats food and statistically everyone who eats food eventually dies, so is eating food a causal link to death? LOL.

Poor oiling, poor maintenance and engine knock will aggravate the weaker nature of the EJ rod bearings and bring on early rod failure.
If the oil film breaks down and becomes too thin, the extra forces created by engine knock can cause the rod bearing to weld to the crankpin and spin the bearing.
Some people advocate "pinning" the bearing into the rod as a countermeasure to spinning a rod bearing, however I have read posts where even engines with pinned bearings have spun bearings in extreme HP applications.
Pinned bearings should not be necessary in a road car.

Another stated weakness is the physical size of the standard oil filter.
Turbo cars create more particulates than a NA engine, which loads up the oil filter quicker. A clogged oil filter will go into bypass circulating unfiltered oil (and at a lower pressure).
I have seen service bulletin notes on the net from Subaru North America stating that the turbo engine oil and filter service interval is effectively half that of a NA engine and turbo lubrication and engine lubrication failures may occur if the shorter service intervals are not followed.

There are also larger capacity oil pumps on the higher output turbo engines.

So, follow Ben's advice....
(1) Use a high quality synthetic engine oil
(2) Change the oil and filter often
also
(3) Install a high capacity oil pump to get the oil where it needs to go (even under loaded filter conditions).
(4) Ensure that the engine tune does not aggravate knock (consider E85 - cheap horse power and knock resistant)

I would possibly add a (5)
(5) Change your oil filter before a track day.