[Full rebuild or top end?]

Normally I would say "do the minimum to keep the car running reliably", but I have been burned by the "new heads on an old bottom end" fix.

 

Yes the cylinders stay good, but I am not so sure the rings keep their spring. I do not know ring wear rate, but they do start at about 5 mm wide, and a from what I know of engineering mechanics, reducing that to 4 mm will reduce the pressure of the ring to the cylinder wall substantially. Math is one thing, molecular interface, material fatigue, and simple cracks another.

 

Testing cold static compression is a standard test, but I a waiting for a spark plug replacement test device (that I can afford) that measures hot combustion compression.

 

Blah blah, in short, new heads on an old shortblock often burn oil. Higher compression may also cause increased pressure on bottom end bearings

 

I for one do not think Subaru bottom ends are "bullet proof". They are aluminum. My experince says they are noisy and loose after 75k miles (nless babied, which I mostly do), and that owners just get used to the noise.

 

I would replace the whole thing with a rebuilt long block. I stand by my recommendation for this builder:.

 

http://www.ebay.com/itm/Subaru-Forester-2-5-Rebuilt-Engine-With-Warranty-/321066261898?pt=Motors_Car_Truck_Parts_Accessories&hash=item4ac10a5d8a

thanks for the advice.  the link advertises a long block for $2050 (with core return) using all oem parts and a 3 yr / 36k mile warranty.  sounds too good to be true.  do you think the builder would provide references from satisfied customers with 36k miles on their engines?

[Full rebuild or top end?]

Hi All,

 

My wife loves her 2001 outback with 2.5l engine and wants to keep it. It has 175,000 miles and within the last 6 months has developed an oil leak at the head gasket.  We re-tightened heads which solved problem temporarily and then added gasket seal to oil as a temp measure and now it is leaking again.  We want to keep the car and are willing to pay for a rebuilt engine but have heard that the bottom end of these engines is bullet proof so are wondering if a top end overhail would be best.  We are skeptical about the quality of the parts that would come in a rebuilt engine.  any thoughts would be appreciated.