Yanmar 4BY High Pressure Fuel Pump

[royf]

My 2012 27' Tug started having some issues last summer with a bit longer to start and a check engine light when throttling up past 1600 rpm. No code was shown on the Yanmar display. Stopping the engine and restarting reset the alarm. So prior to winterization here in Wisc (on the Mississippi) I had both fuel filters changed.

This spring we put it in the water and it wouldn't start. The mechanics came out to the dock and checked over a bunch of stuff (they're mostly outboard and inboard gas guys) and brought it back to their shop on the trailer. Eventually they changed out the solenoid fuel valve as it 'wasn't clicking'. That didn't help.

A mechanic at another marina said he could get it fixed so we trailered it there and he's decided after hours of troubleshooting that it's the high pressure fuel pump. There's no one to rebuild or refurbish them and a new one come from Germany with an installed cost of (well) used car. The folks at Ranger Tugs offered suggestions but the mechanic said his troubleshooting confirmed pressure to the pump and nothing coming out. He's trying one more option with 12 v on the solenoid to keep it open in case it is actually still the problem.

The engine has about 350 hours, so pump failure seems remote. Has anyone else seen this and dealt with it? Are there locations in the US that can work on or sell pumps?

I used to own a 50 year old airplane so I'm familiar with parts availability issues.

Thanks in advance!
Roy
Pepin, WI

 

[Gonad]

Have you replaced the fuel filters

 

[royf]

Have you replaced the fuel filters

Yes. Just before winterization. When launched in the spring it wouldn't start. The priming steps in the 4by manual were followed.

 

[Gonad]

Can you hear the electric fuel pump running. If so is the fuel being delivered to the high pressure pump.

 

[Gonad]

If I was you look for a Yanmar dealer, plant equipment etc. They should be able to connect to the ECM and be able to see fuel pressures etc. It sounds fuel related.

 

[royf]

Yes, there is significant pressure to the low pressure inlet of the high pressure pump and the codes on the ECM were read with the Yanmar interface cable in place. It does appear to be fuel related.

 

[CaspersCruiser]

Is the 350-hour engine original to the boat? If so, that’s very low hours for a 14 year-old vessel, an average of 25 hours per year. That also means that there was very low turnover of the diesel fuel in the tank. That can lead to formation of microbial sludge that can cover the fuel pickup screen in the tank with tar and restrict the flow of fuel. A friend’s low-hour 2012 R27 had that very thing happen.

 

[jeffhowell1]

I own 2011 R-27 with same engine. Last summer boat had problems starting and was running rough when it did. One mechanic here in Anacortes, WA diagnosed fuel pump problem. Took it to mechanic up in Bellingham that works on fishing boats and has much Yanmar engine repair experience. Turns out problem was the glow plugs were shot. Had the glow plugs changed, and engine has run fine ever since. If you have never changed glow plugs, this is certainly worth checking out.

 

[royf]

I own 2011 R-27 with same engine. Last summer boat had problems starting and was running rough when it did. One mechanic here in Anacortes, WA diagnosed fuel pump problem. Took it to mechanic up in Bellingham that works on fishing boats and has much Yanmar engine repair experience. Turnout problem was the glow plugs were shot. Had the glow plugs changed, and engine has run fine ever since. If you have never changed glow plugs, this is certainly worth checking out.

No one's mentioned glow plugs as the issue - just that there doesn't seem to be fuel getting through the system. Thanks!

 

[Trisailor]

Recently had a similar problem on my 4BY2-180 in a 2011 R27 (830 hrs on engine). Turned out to be the relay on the ECU that controls the low pressure fuel pump. There are several posts on this forum discussing the same issue. Just search 4BY2-180 won't start. In my case the engine quit and we had to be towed home. Engine would start/run until the relay overheated, consequently cooking the relay and socket. Apparently the windings in the fuel pump age and start drawing more than the 8.5 amps the relay is rated for and overheat it. I replaced the pump and relay/socket and my baby is now running like the swiss watch she is.

 

[William Sanborn]

Recently had a similar problem on my 4BY2-180 in a 2011 R27 (830 hrs on engine). Turned out to be the relay on the ECU that controls the low pressure fuel pump. There are several posts on this forum discussing the same issue. Just search 4BY2-180 won't start. In my case the engine quit and we had to be towed home. Engine would start/run until the relay overheated, consequently cooking the relay and socket. Apparently the windings in the fuel pump age and start drawing more than the 8.5 amps the relay is rated for and overheat it. I replaced the pump and relay/socket and my baby is now running like the swiss watch she is.

Had a crank and no start on my 2011 RT 27 with the 4BY. Checked the fuel pump fuse was OK and looked at the Relay and it was fried. New Relay and holder and all is OK for 3 years. This is all inside the ECM box.

 

[Gonad]

Yes, there is significant pressure to the low pressure inlet of the high pressure pump and the codes on the ECM were read with the Yanmar interface cable in place. It does appear to be fuel related.

Do you have the codes

 

[Gonad]

No one's mentioned glow plugs as the issue - just that there doesn't seem to be fuel getting through the system. Thanks!

Glow plug trouble will cause the engine light on and buzzer to sound. Warm the engine coolanr to above 50C then turn off for 10 seconds and restart. The engine runs fine just need to shut up the buzzer. Glow plugs are a cold start aid also used to cut emissions down.