Can 2.5T Cams Be Installed 180 Degrees Out And Create No Compression On All Cylinders?

FREEBUSINESSES · Post by **FREEBUSINESSES** » 16 Oct 2020, 13:58

I know, it sounds crazy, but I acquired a 06 XC70 with 2.5T and a hack so called mechanic attempted to replace exhaust cam seals which was leaking badly. Engine was running before taking off can sprocket. So here is my dilema, car would not start, I checked compression, and practically zero on all 5 cylinders, 1 had 30 LBs, 5 had same, others had dead zero??? So I thought the worse, they screwed up timing and wiped out the valves which as most know is common issue with these no tolerance motors.

OK, I have don several head rebuilds, no issues. So here is what I found, there were nicks on pistons, but I did a valve leak down test and all valve were good??? I had already ordered a full set of new valves, so I replaced them with valve seals, lapped in new valves having cleaned up carbon on head and piston tops along with all surfaces. Put head on, timed, with locking tool, but same issue, no compression to speak of. So I am stumped, triple checked timing, checked piston one just before TDC, so given he had sprocket VVT off and did not have locking tool, could he have put cams back in 180 degrees out??? I know, defies logic as there was no cam to piston issues, but for the life of me, I can not figure out what is wrong.

Does anyone know what the cam ends are set at, I saw conflicting information and wondered if cams have serial part numbers in different motors are imprinted on cams differently. I just put cams back in same position they were after timing and properly torque settings which was left loose. The SN imprint is on top of cam on intake, and bottom on exhaust. Anyone remember if this is correct or reversed by chance. I didn't want to risk killing new valves even turning over by hand first. As I mentioned, I saw conflicting information on pictures of proper cam installations.

Thanks,

Post by **jimmy57** » 16 Oct 2020, 16:44

Intake and exhaust cam swap can cause this. There is usually, but I can't attest to ALWAYS, are part numbers on back end of cams and there will be "I' and "E" at the end of the part number screen. Reversing the offset up vs down would not do it. Both offsets up or down gives valve contact as I recall from trying many combos once as a test.

FREEBUSINESSES · Post by **FREEBUSINESSES** » 23 Oct 2020, 11:23

Thanks, was curious if this was even possible. The cam lock tool seems to only fit one way properly, but given the intake cam was chipped on end, I wondered if the tool was at fault.

Post by **abscate** » 25 Oct 2020, 05:19

If you put the cam tool on upside down and didn’t use the “ holder piece” you could lock cams 180 out. There are also some junky cam hold tools out there that if you cheap out, they teach you a lesson about that.

FREEBUSINESSES · Post by **FREEBUSINESSES** » 01 Nov 2020, 16:31

Thanks, was curious as i am stumped as I checked timing a dozen times, and tool was $60. and I have used it many times with no issue, my concern was if it was possible to have cams in 180 degrees out of whack, and there is no valve interference. I am at total loss. seems impossible to have zero and 15 lbs on just one and five.

Sweedy · Post by **Sweedy** » 23 Jan 2021, 15:12

Did you figure it out? Im having similar problem , 60psi in all cylinders. I replaced headgasket, timing belt.

Jraptor2000 · Post by **Jraptor2000** » 04 Oct 2024, 10:27

Did anyone resolve their issues here?

Jraptor2000 · Post by **Jraptor2000** » 04 Oct 2024, 10:29

This is current with crank at lock. Is this the correct orientation? I do have the locking tools but they aren’t of highest quality and seems they fit either way.

Engine is B5254T12 from 2016 Xc60.