Caterpillar 314C LCR stalling under heavy load

[Jason Stephenson]

Good evening folks. I have a Cat 314c lcr. I bought it a while back and have restored most everything that needed work. I don't know anything on the history of it, other than it had been setting for quite some time before I bought it. When I took it out to use it, I noticed that it ran very well, but when you dig with it under a heavy load it will pretty much stall itself out. I completely cleaned the fuel system and replaced all the fuel lines. Didn't help. I was told this has some kind of sensor on the hydraulics that is supposed to keep it from stalling the engine under a heavy load. Any suggestions would be greatly appreciated.

Thanks
Jason

 

[heymccall]

You cleaned out fuel system?
Did that include removal of the water separator and running a wire or air through the inlet port?
Did you also find and clean the screen in the lift pump inlet banjo bolt?

Is your machine equipped with a display monitor or just 3 gauges, like mine?

 

[Jason Stephenson]

Yes. Cleaned out entire fuel system. i am not familiar with the screen in the lift pump however. Where exactly is this screen? My machine doesn't have the display. Only the gauges like yours.

 

[heymccall]

The white thingy inside the bolt thingy.



It is also possible to find that screen in the inlet side of the water separator, like on my Mitsubishi powered Kobelco

 

[Jason Stephenson]

I will take them apart in the morning to see if I can locate it. I definitely don't remember seeing that one.
Thanks for the info.

 

[AzIron]

There is a roughly 250 dollar solenoid on the pump that destrokes it as engine rpm drop mine went bad and I could stall it it's easy to replace

 

[Acoals]

Before it stalls out, is it making good power? Does it feel like it is making normal digging power? If it is a fuel issue it seems like it would be generally low on digging power.

 

[Jason Stephenson]

Had a local mechanic look at it today. He did several tests on it and said that it has to be the Proportional Valve (PRV). I ordered one from CAT today. Should know for sure tomorrow.

 

[Jason Stephenson]

Well changed the PRV. Still doing the same thing. Seems the ecm is sending info according to computer, however PRV doesn't seem to be receiving the signal. Assuming I will have to check wiring.

 

[heymccall]

PRV calibration should've been checked before shotgunning parts at it. And, anytime the PRV solenoid is changed, it should be calibrated. But, if the fuel system isn't up to snuff, it'll all be for naught.

Before calibration, the engine needs to be up to snuff and on hot oil. Since there is no monitor, youll definitely need someone experienced, and equipped with ET.

I think it can be done without ET, but, I wouldn't know where to start.

 

[Jason Stephenson]

Hey Guys. Sorry for taking so long to get back with the results. So after a few thousand dollars from the local Cat dealership they determined the power wire from the ECM had gotten corroded. Apparently the ECM was getting voltage, but not enough. So when simply not being used everything looked fine. That was why they thought the PRV was not working, because it simply wasn't. The ECM wouldn't tell it to. I have worked on quite a few issues in my time, but intermittent electrical issues are at the top of the list as the worse. Everything is working great again. Thanks again for all of your help.
Jason

 

[WWGConstruction103]

Same machine and same symptoms having a hard time finding ecm wire referred to in this forum

 

[WWGConstruction103]

View attachment 294582
Same machine and same symptoms having a hard time finding ecm wire referred to in this forum

 

[Nige]

Same machine and same symptoms having a hard time finding ecm wire referred to in this forum

Post a Serial Number and I can help you with an electrical schematic.

From the sounds of the posts above either one or both of the permanent battery or the switched ignition supply to the ECM the wire (or a pin/socket in a connector) was corroded preventing the ECM receiving full voltage. At least that’s how I read it.

 

[heymccall]

On my PCA 314CLCR, I had to replace the outdoor fuse panel, years ago, due to water entry from the backside. Made a rain diverted for the new one.

 

[David Braun]

Post a Serial Number and I can help you with an electrical schematic.

From the sounds of the posts above either one or both of the permanent battery or the switched ignition supply to the ECM the wire (or a pin/socket in a connector) was corroded preventing the ECM receiving full voltage. At least that’s how I read it.

Thank you for your assistance. Here is my serial number: CATO314CHPCA00165

I appreciate your help

 

[Nige]

Schematic on the way. Check your messages.