I replaced my cylinder cooling head over the weekend (last one had some cracked fins). Now it seems like there is more compression when cranking over the engine. I had been able to get it started once for a few minutes, and ever since I have not been able to get it started. I use the rotostart and it has a hard time turning over even with fresh batteries in the rotostart. It seems to have more compression and wears down my batts real quick. I tried to crack the glow plug a little and still no luck. Any Idea's?

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