Yanmar 1GM10 TEMPERATURE

[toughy]

Hello everybody, this is my first post,hope someone can point me in the right direction! The yanmar 1GM10 in my Vega has been problem free since buying the boat one year ago.Last saturday, after returning from a lumpy ride back to harbour, for the first time since I bought her, the alarm buzzer on the Yanmar engine panel activated when I stopped the engine and turned the ignition off, this was accompanied by two of the three red lights showing, I turned the ignition back on and they stopped! I had a meal and took her out again for an hour or so,sure enough the episode repeated itself again. I started the engine the following day and ran it for about twenty minutes, there was no repeat of this problem. As an add on, I now notice after running her today for twenty minutes at one third throttle, the water pipes are cold, as well as the exhaust manifold, the thermostat housing and cylinder head are all touchable by hand
I apologise for the length of my spiel!! Any ideas? Many Thanks.

 

[Tranona]

Almost certainly poor connections in the wiring loom. The main connector probably needs cleaning. Check all other connections including the sender units. It might be a duff temperature sender so worth replacing that as well.

 

[agurney]

I've had the temperature alarm go off in lumpy seas in my 1GM10/Vega, but I've put it down to catching air in the intake when I've been pushing hard. It goes away when things calm down.

 

[afterpegassus]

habit

A habit I've got into from being in similar situations is having a quick glance over the side to check if water is coming from the exhaust. It only takes a second before you dive for the shutdown and narrows the search for the cause of the alarm considerably.
I appreciate your engine did not appear to be overheating.

 

[Severnman]

Have noticed similar when being in a lock chamber that is being filled pretty quick! Definitely sounds like air being sucked in cooling intake.

 

[Bilgediver]

Hello everybody, this is my first post,hope someone can point me in the right direction! The yanmar 1GM10 in my Vega has been problem free since buying the boat one year ago.Last saturday, after returning from a lumpy ride back to harbour, for the first time since I bought her, the alarm buzzer on the Yanmar engine panel activated when I stopped the engine and turned the ignition off, .

Disregard some of the replies as the kind folk did not read your post!!!!

If the alarm only sounded after you stopped the engine and contnued after you turned the ignition off then you could have an electrical fault. I would agree with those about checking connections.

It seems you also may have a stuck open thermostat as the cylinder head should be just too hot to touch when running a while. Running too cool will put condensation in the oil which may appear as creamy sludge at the inside of the filler cap.

In these days of polluted water I would suggest getting in the habit of looking at the exhaust from time to time to see what is or is not coming out when the engine is running and not only when the alarm sounds.

 

[steve28]

the problem with your post is you dont mention which of the lights was on at the time the buzzer sounded, it could be oil or water causing it. the two lights that came on could be the normal two (charge and oil)


More testing is needed to find out which is causing the problem.

Steve

 

[afterpegassus]

In these days of polluted water I would suggest getting in the habit of looking at the exhaust from time to time to see what is or is not coming out when the engine is running and not only when the alarm sounds.

Quite the seed I was trying to plant with my previous post.

 

[boatmike]

Hello everybody, this is my first post,hope someone can point me in the right direction! The yanmar 1GM10 in my Vega has been problem free since buying the boat one year ago.Last saturday, after returning from a lumpy ride back to harbour, for the first time since I bought her, the alarm buzzer on the Yanmar engine panel activated when I stopped the engine and turned the ignition off, this was accompanied by two of the three red lights showing, I turned the ignition back on and they stopped! I had a meal and took her out again for an hour or so,sure enough the episode repeated itself again. I started the engine the following day and ran it for about twenty minutes, there was no repeat of this problem. As an add on, I now notice after running her today for twenty minutes at one third throttle, the water pipes are cold, as well as the exhaust manifold, the thermostat housing and cylinder head are all touchable by hand
I apologise for the length of my spiel!! Any ideas? Many Thanks.

Many possible answers. Firstly it is always a good plan to allow the engine to tick over for a while at low revs out of gear before switching off. Sometimes belting it and then switching off without a period of tick over does not cool the engine properly and can cause problems. However unless you have the panel live when you switched off the alarms should all be deactivated and only sound when the panel switch is on, so I think you have an electrical fault somewhere.