I would check everything. 1. cables from battery up into powerhead where the + and – (big) cables connect to the starter and ground. Are the battery connections solid? Grungy connections have high resistance, which will hurt.2. Connect a volt meter across the battery and hit the starter. Does the voltage drop to 8 or less? If so either your starter is dragging badly, or the battery is bad.3. With everything off is the battery at +12.5 or so? If not, it is suspect.4. Put the muffs on, turn the water on, and with the voltmeter across the battery, have someone crank the motor. Does the voltage jump to +14 or so (at least +13.5)??? If not, then you are not charging and need to get your charging system looked at.It should not take too long with a voltmeter to figure out what is going on.If after step 3, the battery seems low, you might check for parasitic drain somewhere. Take the volt meter, switch to amps, and disconnect the + battery lead. Connect the red voltmeter (now an ammeter) to the + battery post, and the black lead to the battery cable bundle you disconnected. What does it read? 100-200 milliamps or less. You should be OK. More? You have something draining your battery. Could be anything from a compartment light that doesnt go off, to an electronic accessory that is “thirsty”, etc… Eliminate the drain and the battery will stop going flat on you.2008 Pantera Classic2014 Mercury Pro XS 200
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