probably one of 3 things. cupseal, valve/poppet, or one of the orings on the ram.
all of them are less than 1 dollar to fix i believe so i personally wouldntbut a ram cap adjuster if you already have one. on the other hand an adjustable ram cap is one of the best upgrades you can get for a timmy so if you dont already have one it is a good idea to pick one up anyways.
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