Fill all six 6V Trojan Plus deep-cycle batteries through a single quick-connect port in seconds. Automatic shut-off valves stop water at the correct electrolyte level every time -- no overfilling, no acid spills, no cell-by-cell guesswork.
Deep-cycle battery banks in RVs, golf carts, and floor equipment demand regular watering -- but removing vent caps, checking every cell with a flashlight, and trickling water into each one is tedious, messy, and easy to get wrong. Overfilling dilutes electrolyte and shortens battery life. Underfilling exposes plates and causes permanent sulfation damage.
The Flow-Rite BG-U36V-7J Pro-Fill replaces every stock vent cap on your six-battery 6V bank with precision automatic shut-off valves, then links them with low-profile 127 flex manifold tubing. Connect your water source to the single external quick-connect fitting, fill until the flow stops, and you're done. The whole process takes under a minute.
Float-controlled valves stop water flow the instant each cell reaches the correct level -- preventing overfill on every charge cycle.
Pre-cut flexible tubing routes between cells and batteries, conforming to tight battery compartment layouts without rigid fittings.
One external quick-connect port serves the entire bank. Compatible with Flow-Rite hand pumps, gravity reservoirs, and inline systems.
Engineered specifically for the Trojan Plus series 6V deep-cycle batteries, ensuring proper valve seating and correct fill levels.
Each automatic shut-off valve threads directly into the existing vent cap opening on your battery cells. Inside the valve, a float mechanism rises with the electrolyte level. When the correct level is reached, the float seals the valve inlet -- stopping water flow to that cell. Because all valves are plumbed in parallel through the flex manifold, cells that need more water simply stay open longer while already-full cells hold closed. The result is a perfectly equalized water level across every cell, every time.
After filling, disconnect the water source. The valves vent normally during charging, just as standard vent caps do, preventing pressure buildup and allowing gasses to escape safely.
The single quick-connect port on the BG-U36V-7J accepts Flow-Rite's standard Pro-Fill male quick-connect fitting. You can connect:
Always use distilled or deionized water only. Tap water introduces minerals that contaminate electrolyte and accelerate plate corrosion.
This kit is designed for banks using six (6) Trojan Plus series 6V batteries, which is a common 36V or paired 12V configuration in RV house banks and traction applications. Trojan Plus 6V batteries are three-cell batteries, so this kit covers a total of 18 cells. The 127 flex manifold tubing is pre-selected for typical Trojan Plus cell spacing. For other Trojan 6V models (T-105, T-125, T-145) or different battery counts, Flow-Rite offers alternate kit configurations.
Pair this watering kit with Flow-Rite's hand pump, inline pump, or gravity reservoir to build a complete no-touch watering station. The Pro-Fill quick-connect standard is consistent across the entire Flow-Rite product line, so accessories interchange without adapters.