Stuck in chapter 4... (spoilers)

[Maharajah]

Yea... so I've been stuck at this part for a while... in chapter 4 I got out of the airboat, went into the building with the 2 tanks inside it and wiped everyone out... at the end there is a crank for the doors outside in the water to let the airboat thru, but it is broken.... any idea what i'm supposed to do here? I've got a wrench from the work table by the tanks, but that doesn't seem to do anything either. Please help! thanks

 

[Lazlow]

Go face the broken crank, and turn to the right - see the barrels? You can take it from there.