Yanmar 4BY2-150 fuel pump relay failure

[jfmetzger@gmail.com]

Hi.
The fuel pump relay located in the ECU has failed 2x in the past 50h. The engine has only 600h. The relay is a special order through Yanmar and/or auto parts stores, and is listed in the parts manual. The female block has been damaged by heat (ref. https://1drv.ms/u/s!AihEq72OvfPSiIJafkD ... A?e=W5cfaR). I think/hope the relay failed as a result of a poor contact in the block, but am concerned the failure may indicate a more serious issue - e.g. with the fuel pump?

I have now replaced the female block with a generic block - carefully making the connections as there is not a lot of wire available in the ECU. It would be best in my view to replace the block if it is possible to obtain one?

Any experiences, advice, etc. will be appreciated. I note the comments in TugNuts that the ECU is mounted on the engine and thus subject to significant vibration - wondering if this contributed to the relay failure?

Cheers,
John

 

[ALICE J]

Yes, I had a similar relay failure and was able to go to NAPA auto store and buy a new relay and also a plug for the relay, but was able to use the original plug, so it's a spare. Only this one failure. Took Mastery Marine about a week to diagnose why the fuel pump stopped, but offered no reason for the burned relay. They suggested NAPA. as I was in Canada at the time. Sorry, I don't have the part number. I have a 4BY180 2011. This happened in 2018 with 1325 engine hours.

 

[CaspersCruiser]

....... am concerned the failure may indicate a more serious issue - e.g. with the fuel pump?

The electric fuel pump failed on my 4BY2-180. The area around the relay in the ECU was discolored somewhat suggesting high current flow. The fuel pump was the failure and not the relay, but the relay was replaced as a precaution. It’s possible your electric fuel pump is failing and causing high current draw. It is beyond stupid having the ECU mounted on the engine with the attendant vibration exposure.

 

[knotflying]

here is the relay from Napa https://www.napaonline.com/en/p/ECHAR6276