2 Spark Plugs Fouling Quickly (1 Viewer)

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I can do that, however, before I do, isn't leak-down more commonly to assess where loss of compression is happening (ie intake, exhaust valve seats, rings)?

If I have good compression (145psi, at 5k' altitude to boot), would a leak down still be the right call here?
 
Just wanted to update here - I solved the non-idle condition when I happened to read a thread on here about the idle circuit and grounding it to make it work. Turns out when I plugged that connector back in, I did so until it clicked once - on the top side. But didn't click in the bottom side of the connector, and it was just enough to keep the idle circuit from engaging.

Still working on the plug #2 issue. Once I fixed the idle issue, and timed it (miraculously at 690rpm!), and did the lean-drop carb adjustment correctly, it seemed that at least at idle I wasn't getting intermittent spark on #2 any longer. Who knows...nothing I did should affect the spark to #2, but I'm going to put some miles on and see if and how quickly it fouls again.

With good compression and a good tune, I'm hoping there are no major issues. Fingers crossed!

And if I'm still struggling with it, I'll break out the leak-down tester to see what I can find there. Thanks all for your help!!
 
I can do that, however, before I do, isn't leak-down more commonly to assess where loss of compression is happening (ie intake, exhaust valve seats, rings)?

If I have good compression (145psi, at 5k' altitude to boot), would a leak down still be the right call here?
If you have bad oil ring(s) you could be seeing a false compression reading thanks to the sealing boost of the oil. But he’s the leak down will tell you where you are losing air from. Rings, valves etc.
 
If you have bad oil ring(s) you could be seeing a false compression reading thanks to the sealing boost of the oil. But he’s the leak down will tell you where you are losing air from. Rings, valves etc.
Seth, thank you for this - learn something new every day. Didn’t know that you could get false readings like that - very much appreciated. Will keep an eye on it and leak down if I get to that point.
 

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