Replace working VST fuel pump?

[DannyMart]

I run a pair of 2005 200 hp HPDI. They have required little in the way of repairs and I have the motors services regularly. The engines have about 670 hours on them. On a recent trip, I attempted to start the motors to return to the dock and the port motor would crank but would not start. We ran back 38 miles on 1 engine at 29 mph– those HPDI have some torque.

My mechanic said it was probably the medium pressure fuel pump when I called to have him take a look at the engine. His prediction was correct. The medium pressure pump in the VST failed and burned up a coupel of relays. He replaced the relays, pump and filter. I haven't run the engines on the water since the repair, but the port engine runs fine on the rabbit ears.

My questions are, would monitoring the VST pressure given me a warning that the pump was gradually failing or do these pumps go quickly from working to not working? I am considering replacing the starboard engine VST medium pressure pump to prevent another on the water failure. Is that a reasonable move or overkill?

[99yam40]

my thoughts are what caused the pump in VST to fail.
was it no fuel in the VST for it to pump and that took it out?

no fuel being pumped means no cooling and lubrication

would hate for you to have a repeat

also running a twin engine motor with only one pushing at high speed mean you are lugging the motor badly as it is propped for both motors to be pushing

[DannyMart]

my thoughts are what caused the pump in VST to fail.
was it no fuel in the VST for it to pump and that took it out?

no fuel being pumped means no cooling and lubrication

would hate for you to have a repeat

also running a twin engine motor with only one pushing at high speed mean you are lugging the motor badly as it is propped for both motors to be pushing

I asked the mechanic why the pump failed and he said, “they just fail sometimes in 12 year old engines”. On the water when the engine failed to start, I pulled the inline, 10-micron fuel filter and the fuel looked fine without debris or water. I looked that the canister with first fuel filter under cowling and it also looked normal. I assumed that after 12 years, one could expect electromechanical devices to occasionally fail.

I realize the one engine run was lugging, but I wasn’t going to limp in at 4 knots for 9 hours or wait hours for sea tow to arrive.