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Trying to pick the best engine out of 2

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OK...I have 2 EA71 short blocks. 1 is supposed to have 10 k on it and the other 56k. Problem is that the 56K engine looks cleaner, as if it had less miles than the 10K. (Both these engines sat for YEARS on a shelf, so they are both a little dusty).

 

What are some good ways to determine the better choice out of 2 engines?

 

Thanks for your opinions!

 

Todd

Edited by SUBARU3

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leak down test.

 

borrow, buy, or rent a bore scope?

 

pull spark plug?

 

pull the valve cover gaskets, poor maintenance, oil changes, etc usually shows itself in black and dirty. well maintained 200,000 mile Subaru heads will look surprisingly good when torn down - very shiny and lacking black nastiness.

 

could pull a head off and check condition of valves and cylinder walls.

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Heads are off. It's just a short block with oil pan.

 

There is still crosshatching on the bores and no ridge that I can feel at least. (Can you really feel those)? Tops of cylinders both had some carbon, one a bit worse than the other.

 

I need to get a bore gauge.

 

I will pull the oil pans and look for "black nastyness".

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It's interesting in that one of these engines is clean, clean on the outside and dirty on the inside and the other one is the exact opposite!

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that is funny. i'd lean towards the cleanest one internally.

 

is the "dirty" one also the one with more carbon on the top of the cylinder?

 

if it's anything like the EA81 and EA82, then the difference between 10k and 50k isn't much for engines that make 200,000+ miles really easily.

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OK...I have 2 EA71 short blocks. 1 is supposed to have 10 k on it and the other 56k. Problem is that the 56K engine looks cleaner, as if it had less miles than the 10K. (Both these engines sat for YEARS on a shelf, so they are both a little dusty).

 

What are some good ways to determine the better choice out of 2 engines?

 

Thanks for your opinions!

 

Todd

 

Inspect the cylinder bores for corrosion or other damage.

Pick the one w/best bores and least amount of wear in the top 1/4 inch of ring travel.Normally it is easy to feel on higher mileage engines.

It will be the one with the least amount of carbon on the pistons,IME.

 

Choice would be easier if the motor was more complete.

I`ve had good results at the junkyard by removing a head(not subes) and inspecting the colour of the exhaust valves.

Lighter colour=higher compression

The ones w/darker exhaust valves always have more wear at the top of the cylinders.

 

Checking the PCV intake in the air cleaner for signs of oil from excessive blowby tells a lot too.

 

Forget about a bore gauge.

I have a Snap-On dial bore gauge.Can`t remember the last time I used it.They don`t work well to measure wear at the extreme top of the bore where most wear is.

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Thanks for the tips. Both engines's cylinders seem about the same, but 10k vs 56K is not a huge amount of difference

 

I think I have picked the one to build up. I am putting together a ton of spare parts into an engine. Better one good engine rather than "stuff" all over!

 

Todd

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