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rangeron33s
Well-Known Member
Just finished up my compression test and need help with the results. But first a little back story. Naught this truck for $900 not running. Got it running after running through some wiring and find it had leaky valves. So I bought some refurbished complete heads from oreillys. Didnt have them checked because they are new. Put them on, following the exact step by step instructions in the tech library. Did everything correct. Started it up, drove it about 20 miles. Took it back home to re torque the lower intake and found coolant in the oil. A lot. So in Hope's it was just the lower intake I bought a compression tester to test it out. Cylinder 1 reads 110 psi, cylinder 2 reads 115, cylinder 3 reads 115, so. Passenger side head seems fine, all the compression is pretty low assuming rings probably got trashed in those 20 miles. Now this is where it gets crazy. Cylinder 4 is at half. 60 psi. Huge leak there. Cylinder 5 is at 145 psi, being the highest compression. Cylinder 6 is at 120. Same as majority. So obviously cylinder 4 is leaking. But what's up with cylinder 5? Theres no way every cylinder is leaking except for 5. If the rest of the "good" cylinders are between 110 and 120, then why is 5 so high considering it is closest to the bad cylinder?
