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540 with 480 anglevalve cylinders


Well-known member
I just did a leakdown with 60 hrs on my cylinders, the cylinders were done by Jurnigan, I did the labor, I found one at 30lbs and another on the same bank at 5lbs, I used only the good stuff including only av gas, both cylinders are leaking out the ex valves, I made sure the pushrods were adjusted (I added ajustable ones when I did the swap) Just wondering if there might be something else to check before removing the 2 cylinders and sending the back? As always thanks again, Mike (I also tried to reseat with a few taps and no luck)
Sounds like "using only avgas" may have caused the problem. It's not unusual for the exhaust valves to get too much lead in the valve guides. You could put a rope in the cylinder to close the valves and give it another test. It sounds like the valve is stuck open a little. Personally, I'd pull the cylinders and have a cylinder shop check it out. It may not be all that bad. Let us know how it goes.
I seriously doubt using the correct gas is the problem...especially with only 60 hrs...take them off and send them to a good cylinder shop.

I thought sending them to Jr was the best thing going, I will hopefully talk with him in the am before taking them back off. I was just hoping I might have missed something before doing the cylinder dance again..