Shetland 27i

[Chapterxv]

Good day.
I have recently bought my first boat Shetland 27i. It has a Yanmar engine and on starting there was an ear piercing alarm and display advising to check engine.
It was diagnosed as a faulty sensor ; possibly water contaminated, on the fuel pump. This was replaced with a new one and seemed to resolve the issue, however after a week or so it is back again. Water is being pumped through the filter and I have tried giving more revs on start up but it doesn’t clear the alarm. Can anyone offer any advice please?

[Clive]

Can’t help from experience but what is the alarm indicating? If poor water circulation possibly the water intake is blocked with debris. Is there a good outlet flow and is water temp ok? Has the boat been standing?
Maybe ask on some of the Facebook groups, they may respond quicker.
Good luck and keep us posted.

[dellquay13]

There is a lot of knowledge on the ybw world motor boat forum about Yanmar engines.
I have a yanmar 1gm10 on my yacht, but it has only overheat or alternator alarms on such a simple single cylinder engine.
The Yanmar motors are really common engines from yachts to dumper trucks and cement mixers, where most Shetlands have outboards, so you may get quicker advice posting on here:

https://forums.ybw.com/index.php?forums ... -forum.14/

[Chapterxv]

Thank you both for the replies.. There seems to be a good water flow but it has been standing for a while I believe. I will look at the other website and make more enquiries. Will post more later.

[DACS]

The alarm buzzer should sound if the engine is overheating or there is insufficient oil pressure. Have you checked the oil?

[Chapterxv]

Thankyou for your reply. I will double check the oil level the pressure gauge looks to be reading okay.

[DACS]

Although you have a good cooling water flow through the strainer, are you sure that the engine temperature is correct? A faulty thermostat could cause all that water to bypass the engine block and just cool the exhaust.

If you are happy that the temperature and oil pressure are correct then I would check the wiring. If the module that controls the alarm cannot read the temperature or pressure then it may well give a false alarm.

[Chapterxv]

Thank you that is worth checking. I can’t get to look until after the weekend but will feed back.

[Chapterxv]

Alarm issue continues which is very frustrating. I note now the bracket that holds the ECU unit bolted to the engine has broken consequently the ecu unit is vibrating all over the place. It is suspected this may have affected the wiring???
I am tempted to remove the ecu unit and replace the mounting bracket myself but just lack confidence in tackling this. Has anyone experienced removing this before?