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Cylinder leakdown test - Royal Oak

1K views 7 replies 5 participants last post by  Paul04TJ 
#1 ·
My 85 suburban SBC is starting to burn oil, blue smoke likes to come out of the passenger side exhaust. Compression is the following (only checked the passenger side bank)

cylinder 2 = 180psi
cylinder 4 = 32psi
cylinder 6 = 12psi
cylinder 8 = 182psi

so now I'm looking at making sure I just need to do a simple fix or start a winter project.

Anyone got a cylinder leakdown tester or know a place where to get it done, the truck runs and starts and drives fine, its jut not very powerful, at least it has 4.10 gears :)
 
#3 ·
I haven't tried that but I will when I get home, but the issue is that the valve cover with the oil cap is on the other bank.

I'm thinking rings or stuck valve(s), as well as bad valve seals. A lot of vehicles with bad valve seals will give a good puff of oil smoke upon start up, but there is more than that going on providing those compression numbers lol.

When I pulled the plugs out on those middle cylinders there was oil on the threads. I'm still kinda putting this truck together/fixing it up. I purchased around May and I've maybe put 2000 miles on it. The engine is from another truck, its kind of a basket case so I'm not surprised if the engine will need a refresh.
 
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