Quick question that needs a quick answer

[MarusGTR]

Okay, so I'm changing spark plugs and while I'm there I wanted to do a comp test (just for shits since I'm running more boost now)

So anyway to do a proper comp test I had to warm up the engine and then depressurized the fuel system. I then followed by removing plug no.1 and it's cracked in two.

Now did that happen because I removed it while the engine was hot or was that a fissure that built itself? Should I proceed to remove all the plugs while the engine is hot?

Obviously it's a catch 22 if I can't remove the plugs while the engine is hot and need a hot engine to do a comp test.

PS: The electrode was super clean, only carbon deposits on the metal end.

[MarusGTR]

Head got cold while waiting for an answer. 160psi across.

[Voodoo_ChildR32]

Rule of thumb is not to remove plugs from a hot head. Can cause breakage and worst case pull the threads out of the head.


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[MarusGTR]

I'd agree if it was running temp but I just let it warm up from cold until the thermostat opened. Only the block/valve covers was hot to the touch. No.1 came out with no problems (except the broken ceramic).

Anyway I assume the forged boys need to do wet leakdowns since they'd have to warm up the rings a lot to get proper seal for a gas comp test?

[bobbo]

The ceramic is so brittle as you know. All it takes is one little knock while pulling the coils off or tap it with the socket.
160 is very good and doing it cold is fine, you'll just get worse case scenario.
and stop being so effing paranoid about the restrictor. It's designed and built to run without it.

PS: The electrode was super clean, only carbon deposits on the metal end.

I'm surprised because you're running pig rich.

[MarusGTR]

I'm surprised because you're running pig rich.

You and me both

BTW, I know, I know.

[GTRADDICT]

Get to temp.
Unplug cas.
Remove all plugs
Go one plug at a time.
You must remove all plugs because air can get "Stuck" in an other cylinder. (air bypassing valves)

[MarusGTR]

I depressurized the fuel system so unplugging the cas isn't necessary.

BTW Rob, it's exactly 160 on all cylinders, no variation. Looks pretty promissing about what I'd have with a hot engine...