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Why would it 'pop' like that?


Lead acid batteries liberate hydrogen gas when overcharged. Normally this dissipates quickly and isn't a problem unless there's a spark nearby. Loose/dirty cables/terminals might cause a spark, but you said they were tight. <img src="/forums/images/graemlins/confused.gif" alt="" /> You might want to check all the connections again and clean them like fasteddy said.

1990 Monty LS 3.0 A/T LWB. KYB front shocks, OME rears and coils. 33x10.5 BFG Muds. 5.29, 2.85, RD110, RD46. 2 bouncys. Aisins. Monte Disco swaybar disconnects. GenII t-arms, idler arm, UCA's, V45W front brakes. 2in BL.