Puzzled on an 803

[TheAlfredo]

Today I started up one of my 803s. Started right up. Let it ran for several minutes to charge up the batteries (has been sitting for months). I decided I’d run it on load. So I turned it off and brought out my load bank. Wired it all in and went to start the genset and nothing. No pump priming, nothing.

so I jumped off another of my 803s thinking the batteries might not have enough charge. Nothing.

checked the dead crank....it was on normal. Tested to see if it cranks...and it does. So not a battery issue.

if I turn the switch to Aux fuel...you hear the aux pump run. But if I turn it to prime and run, nothing
After switching it to start, starter doesn’t engage. Switch to off and back to prime...over voltage light is on. Reset the light...switch to start and nothing. Switch to off and back to prime, over voltage light comes on again.
Any thoughts?

 

[G744]

It is said to hold it in start for a short time.
DG

 

[G744]

It is said to hold it in start for a short time.
DG

 

[TheAlfredo]

Yes, I know to hold it in start until oil pressure is up. But it isn’t cranking at all. So it won’t have any pressure

 

[kloppk]

If the overvoltage light is on this will prevent the primary fuel pump from running and prevent the starter from engaging. When the fault monitor thinks there is a fault the relay K12 is tripped killing the starter and fuel pump. K12 is the fault relay.
I suspect your K4 Overvoltage relay may be the culprit or the fault monitor itself may be bad. I've had to repair a couple of fault monitors lately.

 

[Ray70]

If you suspect the fault indicator, simply unplug the white ( natural ) rectangular connector on the back side and try starting it again.
Unplugging it usually bypasses all the safety's ( or at least most, I never tried overvoltage )

 

[Guyfang]

Correct.

 

[TheAlfredo]

If you suspect the fault indicator, simply unplug the white ( natural ) rectangular connector on the back side and try starting it again.
Unplugging it usually bypasses all the safety's ( or at least most, I never tried overvoltage )

so unpluggingthe fault indicator worked. It primed and started. Unplugged it back in and changed out the K12 relay and it worked a couple times and then it went back to faulting. I put back the original relay and it worked.

since I had the top cover opened. I vacuumed and used compressed air to clean out the compartment.

it’s still working and I load tested it today. I hate it when something starts working when you didn’t fix it.

 

[Ray70]

Don't feel bad, there are several components in that machine the will "Die" and then start working either by whacking with a hammer or just removing and shipping through the mail ( K1 Relay for one example ) or sometimes just a short ride in the back of a pickup will occasionally cause issues with fuel gages, no fuel lights etc.
Just another one of the gremlin you eventually learn how to tame.

 

[TheAlfredo]

Don't feel bad, there are several components in that machine the will "Die" and then start working either by whacking with a hammer or just removing and shipping through the mail ( K1 Relay for one example ) or sometimes just a short ride in the back of a pickup will occasionally cause issues with fuel gages, no fuel lights etc.
Just another one of the gremlin you eventually learn how to tame.

I have 2 more I need to go through. I’m sure I’ll be posting on here. One won’t start...has fuel all to the injectors. I’m thinking it isn’t making it past.
The other runs perfect with a 8kw load. I put 9kw and it bogs down and turns off....hoping it’s a fuel issue too.

 

[Ray70]

Ok, probably should start new threads for the other gens, but to get you pointed in the right direction:
1) on the one that won't start, how does the compression / cranking speed sound compared to the others? If it cranks faster and without the compression pulse sound you may have carbon buildup hanging the valves open, but we need more info to diagnose.
2) on the one that won't pull 9Kw, very likely could be fuel. If it bogs with no apparent smoke etc. it could very well be a fuel starvation issue with clogged filters or a weak pump. Just last week I sold a really nice 803, I did the well nut and fuel lines on it the day before the buyer came so I load tested the night before with no issues. Customer shows up and now the machine is starting and immediately dies. Once I get it running it won't pull more than 50% load, but it was at 100% just 12 hours earlier.
Turned out to be a weak 1074 fuel pump. Swapped it out quick and gen was back to normal and customer was happy.

Post up a couple new threads with more details and lets get the other 2 fixed!

 

[G744]

I've had several gensets over the years that ran fine, then die. Start it up again, same scenario.

In each case it was a shop rag in the fuel tank. It got sucked up to the inlet, stopped the machine. It falls away then, and repeats upon startup.

Not funny.

DG