Paguro 4000 not starting

[skipperpete]

Assuming that I’m the mechanic that attends the call out here’s the quick and skinny on what I’d do after dipping the oil , checking the coolant and closing the seacock
1. Verify clean bubble free fuel flow through suction/supply side including solenoid.
2. Loosen the injector pipe at the injector and verify HP fuel flow ( usual start sequence)
3. If no fuel here, check start solenoid voltage.
4. Attach master oil pressure gauge and verify oil pressure. If good, move to 5
5. Check temp switch. If not grounded move to 6
6. Attempt start using auto decomp lever and coldstart device and be ready to open seacock.
This takes about 5 mins to do and depending on the results, establishes what to do next. A lot of what to do next depends on getting clean fuel flow through that damned fuel solenoid (which has to be about the dumbest commercial solution to engine shutdown) and fuel out of the injector pipe.
Your wiring diagram shows fault to earth shutdown.
All loads to be off for these basic tests.

[lawrence_craig]

Thanks Pete, that's super helpful.

How do I test if sensors are grounded/fault to earth? Is it just test if voltage goes to an earth point when powered?

[skipperpete]

The sensors are normally open when the engine is running and then close if there’s a fault. In your wiring diagram the engine would be stopped because the oil pressure switch is closed. Take the wire off the sender to neutralize the shutdown but you need to know that you actually have oil pressure before neutralizing the oil P switch to avoid doing harm to the bearings.

[lawrence_craig]

I managed to get a bit further today in that it’s definitely a control circuit issue. I cleaned all the contacts on the sensors and also the control panel plug. It started up and ran for a few seconds then shut down. No more “alarm buzzing” when trying to start. I guess it’s now to find what’s stopping it. I suspect the control panel plug or the control panel itself.

Any way to bypass the control panel to stop it shutting the engine down?

[waltini]

I have the same engine in a different brand generator. To check fuel flow I would take off the fuel return line. As soon as i turn the ignition on and prior to starting I can hear the fuel pump going and fuel will be coming out the return line.
On mine only the oil pressure switch stops it from starting and I have to depress a button on the control panel to override it.

I have a relay on the back of the control panel and if was comfortable that the oil pressure switch was okay I would replace the relay.