QSC 540 – 449 fault/alarm code

[Kraig Kilger]

I received a 449 fault code/alarm yesterday at cruise (fuel pressure very high) on one of my engines. The engine runs fine at lower RPMs, but when I ran it up for a minute or so after the alarm to test it was burning substantially more fuel than the other engine and it sooted the transom (so there actually appears to be more fuel being injected into the system rather than a faulty reading).

After being shut down for a few hours the fault code has cleared on the display, but I have only run it at idle for a short bit since this occurred and I suspect the fault is likely to happen again if I were to run it up to higher RPM’s under load.

I read a few posts on this forum suggesting replacement of the fuel lift pump for the same fault code on a QSB. Can I assume the same protocol would apply to a QSC?

In speaking to my mechanic, his initial thought is a bad injector, but he also didn’t have the benefit of the specific fault code.

Any thoughts as to how I should best approach this are much appreciated. Thank you.

Topic

[Kraig Kilger]

Thanks Tony!

Big shout out to Tony! I ordered the fuel control actuator on Monday and they had it at my front door yesterday afternoon. Just installed it and ran the boat and it’s back to running as God had intended. Thank you!

[Tony Athens]

QSC-QSL9 Fuel actuator

Not voltage specific–Sensor are run the the ECM ( 5VDC output ?? )

Not under pressure– Maybe some bleeding but maybe not

Torque = common sense————————-Not sure what you are referring to as to twice ???

[Kraig Kilger]

Installing the replacement actuator??

Tony – Thank you as always for your insights. I’ll place the order for the actuator. May I ask a few follow up questions:

– My QSC’s are 24 volt. Is the actuator voltage specific, and does the actuator I purchase depend on which model QSC I have?

– It looks like a very straightforward replacement (3 bolts and a wire harness). Do I need to worry about the fuel being under pressure when I remove it, and will I need to bleed the system after I install the new one?

– Your website pics reference that the bolts need to be torqued twice. I found something on line for a QSB actuator stating that the first torqueing is at 27 in/lbs, and the second torqueing is at 62 in/lbs. Is that correct for this unit?

[Tony Athens]

QSC alarm

Replace the fuel actuator on the CR pump–Most likely cause.. Pics of it on this site.

[Author]

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