Volvo 2.5T has new rebuilt head, all new valves, seals, etc., timed, but all cylinders are near zero compression
I am stumped, have done a dozen head rebuilds and have never experienced near zero compression on all five cylinders. Triple checked head and did a leak down test. and all checked out. Set timing up with cam lock tool, spot on, and what is strange is I get 15lb. from cylinder one, and when I apply air I see slight bleed over to cylinder three. Cylinder two bleeds over to four, and only five does not bleed over to other cylinders. Five has 30lbs., so I did wet test with oil in cylinders, helped ever so slightly, so I am stumped, any ideas.
I picked this up and owner had exhaust cam oil seal leak, a friend of owner did repair, but could not get it running. When I got it I found timing out and VVT cam bolt not properly torqued. So I checked compression, it was the same as it is now. I pulled head assuming valves were wiped out, but they were not, did a leak down, all was fine, but there were dings in piston tops. So that is the back story, seems I have exactly the same problem after rebuilding head. What else could cause no compression? Cylinder walls looked fine, I cleaned piston tops, and sprayed oil to keep from rusting as head was off for a few weeks, but covered, didn't see any seepage of oil down pistons. No visible cracks. Engine was running before oil seal job. Any ideas?
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