Good day all,

I have a 2007 Mercury Verado 250 Fuel Supply Module that potentially had a bad lift pump. I changed all parts in the FSM to avoid having to take it all apart again and when I installed it I filled the bowl and connected all hoses, it primed up fine and so I turned over the motor and the FSM casing burst. I thought maybe the casing was potentially suspect, I had another FSM I was going to rebuild, which was lucky so I built that one up and installed it and again the casing Burst. What could cause that! Obviously something is creating too much pressure but I would think there is a relief somewhere in the system but I cannot find info. Any help would be appreciated. Thank you
(I have done this before with no issues on my other motor)

It does have a pressure regulator, is it possible you swapped position of pumps put the high where the low should be? I always replace the whole module if it is available liability reasons.

Hey Tony thanks for the reply. There is only one way they can be installed into the top of case.

I am wondering if the float is working opposite which is keeping the lift pump on therefore over pressurizing the system. Anyone have thoughts on that?