2004 200hp HPDI oil problems

[astrobud311]

Hey guys this is my first post. I just bought a grady with twin HPDI's the stbd motor is having oil transfer issues. I know there have been a million threads on this and I have read all of them but I am stuck and at a loss. I went through the troubleshooting manual, here is the run down. Had the boat out and low oil alarm went off, shut the motor down and refilled the engine oil tank and ran her home. The remote oil tank is full. With the key on I tried the emergency switch and pump did not come on. Yesterday I put power straight to the pump, it kicked on and transfered oil to the engine tank. I have continuity at the remote tank pump, emergency switch, and oil level sensor in the engine tank. Went through the trouble shooting steps today, I grounded the blue wire going to the remote tank pump and it came on and pumped oil. The next step says "Test the PBS control unit black wire for proper connection to ground" I traced the wire and I don't know where it grounds to, looking at the schematic i can see it goes to a ground but I don't know where. The black ground wire runs to a connector on the outboard side of the motor and runs down to ??????

It says if the ground is good replace the PBS control unit. I have no idea where the PBS control unit is on this motor. Can anyone help me out with this issue? I've looked through IPB's and the service manual and cannot find anything about the Precision Blend System (PBS) control module. Thanks in advance for your help guys!!

[astrobud311]

Ok well after looking at the wiring schematic I see the black wire coming off the remote oil pump goes to a hard ground. Where it's at I have no idea? However the blue wire coming off the oil pump goes to the emergency switch then it goes to the ECU. Is that what the guide means by CDI, are they talking about the ECU? Does that mean if the ground connection is solid I have to replace the ECU? Oh man I hope not! Help please!!

[Tucker]

In the 2 or so years I've been on this forum I don't think I've ever seen this problem caused by a bad ECU. Since your emergency switch fills the engine mounted tank; it's gotta be the float switch in the remote tank. I recall seeing many posts about HPDI oiler issues. Spend a little more time researching and print out the posts. Many guys have lived this problem.

[astrobud311]

Thanks for your input man, I have read every thread on here about the oil transfer issue probaly twice, and have printed several out. It may be the remote oil tank sensor, the blue wire I grounded to get the pump to work does run to the emergency switch from the remote oil sensor. I still need to figure out where the hard ground is coming off the remote tank pump. Thanks again for your help, I am praying it's not the ECU.

[Tucker]

Ive read a lot of Rodbolt's threads about electrical problems and seems the ECU controls ground paths. So you running the blue to ground bypasses the ECU.

[astrobud311]

Got it figured out today, went back through the whole system, when my buddy was actuating the emergency switch I had the remote oil pump and sensor connector in my hand and it was clicking on and off as I moved the wires. Looked at both ends of the connector, all pins and receptacles were in good shape and none of the wires were loose? Check it again and it was clicking in and off, cut the damn connectors off and spliced the wires together and walla worked like a charm. Drained the engine oil tank, turned the ignition on got the alarm, oil tank filled! Now I gotta figure out this RPM split between the two motors, this should be fun

[Tucker]

Are you saying both ends (male & female) of the connector looked good but there was still a problem inside the connector?? WTF, first I've heard of that. Good luck!

[astrobud311]

Yep, both connectors looked fine, no corrossion, clean, all pins and recepticles were clean and straight, All wires were secure but for some reason when you wiggled the harness it would cut off the pump. We spliced everything together and I was shaking the crap out of the harness without the pump cutting off and the system worked as advertised.