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Subaru legacy outback 1997 no compression? EJ25 DOHC Rebuilt heads/piston rings/gaskets/seals/timing Answered

I toasted my Subaru about a year ago and just now am able to work on it. Had the heads rebuilt, piston rings,gaskets and seals...I do a compression check and zero on all 4.
What else could it be? The lifters? I'm really at a loss and trying to fix it.
Been contemplating getting an actual mechanic to come out and look it over, but I would rather try everything I can first. Anything at all to point me in a new direction would be awesome.

5 Replies

rickharrisBest Answer (author)2017-07-01

A valve is open/stuck.

The piston is passing pressure - perhaps the rings weren't assembled correctly.

The head gasket is leaking but that would be a very serious leak to get zero compression. I would go for a valve first.

Compression has fairly limited options.

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Gtx864 (author)2017-07-01

we figured it out last night. All 8 of the intake valves are are seating properly. Literally all 8 are staying open just a hair. They can be closed by thumb, obviously not while assembled. Managed to close a set of them and was able to start getting compression. I think we have it handled at this point. Thank you both for your responses. You guys (gender non specific)are life savers! :)

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steveastrouk (author)2017-07-01

You haven't set the timing correctly.

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Downunder35m (author)2017-07-01

No compression at all after a rebuild usually means the timing is off.
Keep in mind the cylinder in question goes ot OT twice in a 4 stroke engine ;)

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