Dealing with a Sany 365C Excavator with a Cummins Engine QSl9 CM2350 this excavator has been giving hard starts and would only start with ether I taught it was my crankshaft and camshaft sensors I change those out felt that it was a fuel problem so I change out the lift pump and also the check valve on the Ecm cooling plate had an issue I change that out and bleed the system now it’s still giving the hard start in using the Cummins diagnostic software no active code just that I notice the fuel rail pressure was only 45 psi I have some videos o f the parameters if anyone wants to have a look at them to offer some assistance
Are there any history codes for pump inbalance
no there hasn't been any codes for pump imbalance what i can say is that when checking the the fuel pressure coming from the fuel gear pump i was only getting 10 psi on cranking and according to cummins troubleshooting manual on cranking i should have at least 30 psi and on idle about 70 psi so since i am not getting the required pressure coming from the gear pump i figure the problem has to be within the fuel gear pump
Ok there are weep holes on those gear pumps. Did you see any fuel drip out or is it wet.
Can you verify that there is no obstruction on the suction side of the gear pump
i'll have to pull it apart to see what i discover i'll let you know what i come up with
Can’t you just run it out of a bucket of fuel just eliminate everything down stream
ok ill have to make some adjustment since the the gear pump is supplied from the lift pump which is connected to the ecm cooling plate
Lift pump runs for 30 seconds on initial start up to prime the system. Then gear pump takes over I would key on see what you getting to pump from the lift. If you get flow from that the check that off list. After that I would see if there is a way to run the gear pump out of a bucket or if there is a spot in suction side to hook up a vacuum gauge to see if there is a obstruction.
ok the lift pump does runs the pressure from the lift pump is 15 psi going to the gear pump to get the gear pump out of a bucket i will have to work on a way to get this done
Any luck