NO Oil Pressure reading

[vicwa67]

This topic has been discussed repeatedly and I have read through most of them. My problem is different, however. I get no oil pressure reading information. But, the low oil pressure alarm is not sounding. The oil pressure gauge background is displayed but no needle to show the reading and just dashes at the bottom of the gauge. Yanmar has updated the i8150 interface with 1.13. But, still no oil pressure information. My second attempt at a solution will be to replace the oil sensor ground wire. I have read the bulletin on this procedure, but before I attempt it, I thought I would just build a jumper wire between the ground on the sensor and the negative post of the engine battery. Will this test show me if my problem is a bad ground on the sensor?

My third attempt will be to replace the oil pressure sensor. Where can I get a sensor and at what price? I have not removed the oil pressure sensor, so I am not familiar with it. If the pinhole described in some of the posts on this subject is just clogged, has anyone just enlarged it? If so, to what affect?

I could not figure out how to attach an image of my Yanmar engine display.

 

[captstu]

Your symptoms, if you have a Yanmar BY series engine, are covered in Yanmar service advisory YASA2014-005-M.

I put about $1200 into having this free advisory installed.

Eventually the two authorized Yanmar shops gave up and Yanmar said I had to ship the engine (and the boat?) to their regional shop at my expense.

I installed a 1/4" NPT mechanical gauge, in was fine.

Then I put in a1/4" NPT idiot buzzer. It gives a reassuring buzz when I start and stop the engine. Much better than a picture of a gauge that is not visible when charts are up.

Skip the grief, put in a $20 oil warning buzzer, much better!


Stuart Bell
Ranger 25: Shearwater
(561) 352-1796

 

[vicwa67]

I built a temporary jumper wire between the grounding post on the oil pressure sensor and the negative post on the engine battery. Still no oil pressure information on the Yanmar display. Guess it is time to replace the $250 sensor.

 

[knotflying]

I suspect your issue is not the sensor. It sounds like you have lost communication between your display and the software module for the oil pressure segment. If the sensor was bad you should be getting an alarm for low pressure. As part of the grounding service bulletin there is also a software update. You swap out your module for an updated one.
You can check functionality of the sensor by attaching an ohm meter to the terminals. I do not have the specific readings at different rpm's on me now, but if you are getting varying ohms at different rpm' s then you can assume it is functional.

 

[captstu]

I replaced the sensor twice at Yanmar's insistence and my checkbook before the acknowledged they could not put the oil circuit back the way it was before they applied the advisory.

Save your money, put in an analog sensor and a buzzer. Less money and far better engine protection.




Stuart Bell
Ranger 25: Shearwater
(561) 352-1796

 

[knotflying]

Okay, here is the info from the detailed engine manual:
If the sensor is defective no P-codes will be generated.
Resistance at 0- PSI = 10 ohm +/- 5 ohm
29 PSI = 52 ohm +/- 4 ohm
58 PSI = 88 ohm +/- 4 ohm
87 PSI - 124 ohm +/- 5 ohm

To test the ohms remove the existing leads and then put your multi--meter leads on each terminal and fluctuate the rpm's from idle to high.
So If you are getting any reading between 10 and 124 ohm at low to high RPM your sensor is good. If it is not fluctuating I would remove it and make sure the small hole at the bottom is not clogged. If it isn't clogged then your sensor needs replacement.
A while back a Yanmar mechanic told me that they were having an issue with the sensor and they enlarged the hole on the bottom of the sensor. I wouldn't do that until I tried cleaning the original hole first and it didn't work. As long as it is assumed that the sensor is malfunctioning, after that it won't matter if you break it. :lol:

Let us know how you make out.

 

[captstu]

I don't believe the problem is the sensor. Yanmar of tried three sensors on my boat when they broke the oil pressure trying to apply the service bulletin sited above.

If the sensor have been defective I believe you are pressure would've been wrong, zero, pinned or something like that. But no, the well pressure needle disappeared indicating to me the software and discovered there was no oil pressure sensor installed and oil pressure display was not enabled for that device.

Since they were never able to fix the problem on my boat we will never know for sure but analog sensor displays typically fail in the way quite different from digital displays. My display is indicating that oil pressure is not one of the items to be indicated on either their Gauge or the city of Gauge built into the Garmin.

The idiot light horn solution I installed is arguably better than the oil pressure gauge even if it were working. The horn sounds at engine start up and shutdown and says to me, "the indicator is working correctly." Since oil pressure is typically not displayed as a default on either the engine Gauge or the Garmin, the only indication you get a low pressure is a nondescript general alert of check engine followed by a light you can't see that says low oil pressure.

The warning before and I have will wake up the dead if it sounds while you're underway. It's a better way to protect your engine and get you better peace of mind. Don't waste your thousand dollars trying to fix the problem you have spend a few bucks and put a horn instead.


Stuart Bell
Ranger 25: Shearwater
(561) 352-1796

 

[vicwa67]

Remember, my Yanmar engine display shows RPM and temperature. But, the oil pressure information is blank (no needle) and the digital reading is just dashes. Here are my test results, but still no answer.

1. My i8150 was updated to 1.13 by Yanmar. Resulted in no change to oil pressure display.
2. I ran a temporary ground wire from the ground terminal (B2001/1) on the oil pressure sensor directly to the negative terminal on the engine battery. Numbers 1 and 2 resulted in no change to oil pressure display.
3. I tested the oil pressure sensor. I disconnected the two wires from the terminals on the oil pressure sensor. With the engine off, I read 9 ohms between the terminals. At idle or 750 RPM, I read 68 ohms between the terminals. At 1500 RPM, I read 91 ohms between the terminals. This tells me my oil pressure sensor is working fine and that I have oil pressure. However, I still have no oil pressure readings on the Yanmar display.

Can anyone confirm the “audible” portion of the Yanmar oil pressure system is still functional. In other words, I have no digital information, but I still have the low oil pressure audible alarm.

Thanks

Wayne Bernhardt
R-27, Tuggo

 

[captstu]

Wayne, The audible function is not functional on my 4BY2 on a 2010 R-25 after applying the above Service Bulletin. The process of applying the bulletin "broke" oil pressure - it is no longer wrong (the purpose of the bulletin), it is gone.

As I stated above, I put over $1k into paying to repair the damage the Yanmar authorized service statiion did when they installed the bulletin.

Yanmar's position is I must ship the engine(and the boat?) at my expense to the regional service center and they will "try their best" to put it back the way it was before they broke it. No offer to give me the money, nor was there a guarantee that after they were done, oil pressure would work again either correctly or as it did before application of the service bulletin.

I was able to confirm that for each of the three sensors they installed (and charged me for), the sensor current varied as the oil pressure changed with RPM.

Ranger (Andrew) helped as much as possible by contacting Yanmar on my behalf, but Fluid Motion's leverage is limited since they no longer buy Yanmar engines (a good decision).

The older Yanmar engines were rock solid - I ran one or another of these for many years with only normal problems. the new engine is just fine until it isn't - Yanmar just doesn't answer the mail any longer.

Install an idiot light sensor, a wire to the helm, and a buzzer - and give up on the digital gauge. Inexpensive, reliable, and tested every time you start or stop the engine.

 

[knotflying]

Can anyone confirm the “audible” portion of the Yanmar oil pressure system is still functional. In other words, I have no digital information, but I still have the low oil pressure audible alarm.

Thanks

Wayne Bernhardt
R-27, Tuggo

I would think if you remove the leads from the sensor and the low pressure alarm is still working, you will get an alarm. Have you spoken to Yanmar about switching out the old software module? This is part of the oil pressure service bulletin.

 

[captstu]

The module on my 2010 R25 was switched twice. The first switch out was as described in the service bulletin and was intended to change the parameters that were causing the erroneous oil pressure reading described in the service bulletin. The second switch out, actually replacing my unit that had the software rewritten with a different unit from Yanmar was done as part of the debugging effort when the first unit cause my oil pressure to disappear. The second mechanic on the project tested the actual pressure with a mechanical well pressure gauge, and also tested indicator lights and horn. He reported the mechanical oil pressure gauge indicator pressure within range, any indicator lights and horn did not go on either an engine start or when shutting down the engine as it should indicate normal Low pressure.

At this point Yanmar said I had to transport the engine to their service facility, not just an authorized dealer, and they would go no further for the repair.

I removed the factory sensor and install the idiot horn sensor and I'm really quite happy with the results. The horn sounds, as it should, when I turn on the engine and don't start it yet. The horn also sounds briefly and shut down when the oil pressure drops and there still some electrical power break. This is the way my 52 Chevy worked and I was quite happy with that.


Stuart Bell
Ranger 25: Shearwater
(561) 352-1796

 

[vicwa67]

I had no oil pressure. Well actually, I had oil pressure all along, I just had no oil pressure reading on the Yanmar instrument pod. It has been a long process and I got a lot of advice and help from Michael Dolifuss and Michael Angland at Yanmar, and Jordan Clore at Mack Boring & Parts Co. Below are the steps taken to eventually solve my oil pressure problem.

1. My i8150 interface was updated to 1.13 by Yanmar - no change, no oil pressure reading
2. I ran a temporary ground wire from the ground terminal on the oil pressure sensor directly to the negative terminal on the engine battery - no change, no oil pressure reading
3. I replace the ground wire for the oil pressure sensor anyway - no change, no oil pressure reading
4. I tested the oil pressure sensor with a ohm meter. (Engine off - 9 ohms, 750 RPM - 68 ohms, 1500 RPM - 91 ohms)
5. I replaced the Yanmar i8150 interface module with a "test" i8150 from Mack Boring - no change
6. I replaced the Yanmar engine instrument display at the dash with a "test" display from Mack Boring - no change
7. I replaced the Yanmar engine wiring harness with a "test" wiring harness and new i8150 from Mack Boring - CHANGE

I now have an oil pressure reading on the "test" Yanmar instrument pod. I reinstalled my original Yanmar instrument pod and then reinstalled my original updated i8150. The oil pressure reading information remained solid. Evidently, my problem was in the Yanmar wiring harness. I now have a bunch of "test" parts to send back and a wiring harness to buy.

Maybe, my process will help fellow Tugnuts.


UPDATE: Just got an email from Jordan at Mack Boring. I just need to send back the "test" components (two i8150 interfaces and one engine instrument pod) they sent me along with my old engine wiring harness. I keep the new wiring harness at no charge. Can't beat that for service. If you ever have a problem, I highly recommend Jordan Clore and Mack Boring & Parts Co.


Wayne Bernhardt
Tuggo, R-27

 

[captstu]

I had the same problem. The Yanmar distributor in s. Florida said I had to bring the boat to St. Petersburg at my expense to get the new harness. I had already put about $1200 into the service advisory that started the problem, and I just had no way to get to Saint Pete, so I converted to an analog warning instead of the built-in digital system.

Yanmar service is very dependent on where you are located. When I was in Annapolis and worked through
Mack Boring I was very pleased. The results in Florida have not been as good.


Stuart Bell
Ranger 25: Shearwater
(561) 352-1796