If the exhaust guides are the ones that are leaking, it will not show up on the plugs. On the exhaust stroke, it just blows it by.
The tool is not 100% needed, but I always use them to insure a good job. (Without, you can roll the seal.
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Benzmac:
Donnie Drummonds
1992 500E (very soon I hope
1981 280GE SWB
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