Hi, I know a similar question has been asked before but it didn’t give proper answer. my cat 301.5 dogs fairly well, tracks well, but the only problem is when I put an excessive load on the machine it stalls, the worst service is the dipper arm, if I’m pulling the dipper back and try to crowd the bucket at the same time it stalls the machine pretty much straight away. I have learnt to deal with it when working with the machine but it makes jobs a lot slower than they need to be. My first thought could be fuelling but it’s recently had a new lift pump and doesn’t struggle to start. Any ideas?
Good day I believe your machine has a load sensing system and from your description it could be lack of engine power maybe a fuel issue or less likely delta P pressure is out of adjustment. Operating the arm using maximum flow while stalling the bucket requiring maximum pressure will make the most demand from the engine. I hope the explanation helps. Welcome to the forum Kind regards Uffex
Thanks for your reply. Any idea where I could find the load sensor?
Good day Alex Subscribing to the forum you have a Cat guy "Nige" he is able to furnish most folk with the hydraulic schematic ect. that you need. Just appeal to him with your serial number and Im sure he will help if he can. Kind regards Uffex
Serial number
5DW07131
That's the engine. The machine S/N is 3YW04015. Attached the hydraulic schematic.
Good day According to the schematic, the machine has a fixed displacement system. This means engine overload is most probably an engine issue. (No load sensing). Sorry if made any confusion. Kind regards Uffex
When the engine stalls, is it easy to restart? If so it sounds like a fuel supply issue. If not it's probably something else. When it's running, does it sound like it's running rough? Any smoke? We can go checking main relief and pilot pressures, but the results don't really mean anything if the engine isn't running properly.
Have you checked the fuel and air filters?
Edit: When the engine stalls, is it hard to restart? If so it sounds like a fuel supply issue. If not it's probably something else.
starts bob on no mither
its got an inline fuel filter like the little cheap transparent plastic ones with the red filter inside. I've seen similar machines with a proper canister filter attached so whether that will make any difference i don't know
I'd remove the entire filter/ priming pump assembly from the machine, remove the priming pump, remove the element, run a wire thru the inlet elbow to ensure absolutely no restriction buildup, and make sure that the Oring between the water bowl and the element is in there.