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Maintenance / Re: Rebuilt Engine - black spark plug at #8
« on: August 08, 2018, 08:55:34 PM »
There is a utube video of a guy a guy checking out of the box aluminum heads mainly for valve angle cuts and leakage. It shows some really surprising things good and not so good. I think you brand was one of the brands. Valve seals would be my first place to look. I might would contact them and tell them you are doing that.