Summary: When burp drafting, if the pump operator leaves the Tank Fill valve open too long, water can overflow from the tank. On pavement, that’s just a cleanup job — but on grass or soft ground, it can get your truck stuck. Worse, if you're drafting from a dump tank, that overflow is wasted water. The fix? Close the Tank Fill valve quickly and begin flowing water to the fire scene or fill site.
Burp drafting is all about creating a smooth, air-free path for water from your hard sleeve into the pump. But there’s one often-overlooked step that can turn a solid setup into a soggy mess — and that’s what happens if you leave your Tank Fill valve open too long.
If the pump operator starts burp drafting with a full tank and leaves the Tank Fill valve wide open, that water’s got to go somewhere. On pavement, it’ll just overflow out of the tank — annoying, but manageable. But on grass, gravel, or any off-road terrain, it’s a different story.
Too much water runoff around the rig can soften the ground and put your apparatus at risk of getting stuck. And if you’re drafting out of a dump tank, that overflow is straight-up wasted water — water that’s supposed to go toward suppression or filling another unit.
As soon as the intake valve is fully open and you're ready to transition to flowing, the operator should rapidly close the Tank Fill valve. That shifts the water flow from recirculation mode to fireground supply, sending water where it’s needed — not onto the ground.
Don’t ignore overflow just because it’s “just water.”
Always assess your operating surface. Pavement and grass are not the same.
Once burped, close that Tank Fill and flow to the fire or fill site immediately.
This small but crucial move keeps your drafting operation clean, your truck mobile, and your water doing the job it was hauled in to do.