Go ahead and laugh, I would but I have a situation I and my friends have never heard of. We have a 350 engine that has been bored .030 with new pistons, rings, bearings, crank turned and new oil pump. The cam shaft was miked and lifters inspected and reinstalled. The heads were cleaned, new seals installed. The issue is the compression reading is a maximum of 60 psi. on number 1 cylinder, 30 psi on number 3, 7, 2 and 8 cylinder. 0 psi on the remaining cylinders. We used two different compression testers with identical readings. We have never heard of 0 psi but this engine has it, new rings, head gaskets and the valves are seated (closed). I know this makes absolutely no sense but would appreciate suggestions on what to check. Thanks!

 

Bad valve adjustment?

 

Camshaft way out of sync?

 

Weird... As Ken said seems like camshaft timing is way off?? I wonder if you could take rocker arms off- then bring a cylinder to bottom of bore, install your compression tester on that cylinder, then turn crank with socket-ratchet on crank bolt, see if some small reading??? Not sure if that would work... but if you did get some compression that way and had none before with rockers on you would know problem is with valvetrain... Good luck... very strange situation. Keep us posted.

 

Back off the valve adjustment and see if that increases compression pressure.

 

He never said it had adjustable rockers. I am guessing cam timing is way off.

 

Rechecking timing marks this morning, will advise. Thanks to everone!

 

With #1 at TDC the rockers on either the compression or exhaust stroke, the rockers arms should teeter open/close on either side of TDC on either cyl #1 or #6.

With #1 on TDC compression stroke #6 cylinder rockers should teeter, if not the cam timing is off.

Good luck!!!

 

The timing chain get set that was installed previously had an adjustable crankshaft sprocket and it was adjusted to maximum advance, when the harmonic balancer and the timing chain cover marks were aligned for number one cylinder the timing chain sprocket timing market was at 10 oclock. Tomorrow I will pull the crankshaft sprocket and set it 0 advance when number 1 piston is at TDC and see what happens. Wish me luck and thanks again.

 

Good luck. If adjusting the timing gears doesn't fix it, you can determine where the compression is going by doing a cylinder leak down test.

 

Wishing' ya luck! Don't put the front cover back until you do another compression test. Once all seems well photograph the gear etc. at TDC compression stroke for later reference then put the cover on.

 

Good advice, Thanks

 

Did you replace the rocker arm rods? Were they all the same length?

 

Just to update, replaced the adjustable advance timing sprocket set with a factory style set and now have 180 to 190 PSI on every cylinder. Thanks for the help!

 

Great news!

 

Excellent. What brand of timing set was the adjustable one?

 

No I.D. on the parts.