Recently you posted some info on an easy temperature sensor alarm.

My fanbelt broke and my Yanmar 4 overheated and blew the head gasket.

I can do the replacement head repair no prob, but need to fit some kind
of sensor to stop it happening again. The raw water flow wasn't
affected, just the sealed water system this time.

I have a buzzer on the control panel but it's only for 'ignition on' -
can I add the overheat warning into that circuit?

--

Molesworth

--
http://www.stcustards.free-online.co.uk/

Molesworth wrote in news:ukmole-
:

I have a buzzer on the control panel but it's only for 'ignition on' -
can I add the overheat warning into that circuit?



Of course! Yanmar even has them! No boat should be without overtemp
alarms....but you knew that, right?

Look in your Yanmar manual. That SAME buzzer is supposed to blast away if
the engine overheats! You may just have a bad sensor, or some idiot
removed it because he didn't like to hear it warning him his engine was
overheating....

Which Yanmar do you have that DOESN'T have a high temperature alarm LIGHT?

If it's got a light, you can easily add a loud alarm to it by paralleling
that light with an electronic siren module from any Radio Shack store.

I can't find any Yanmars without overtemp alarm circuits.....

In article ,
Larry wrote:

Molesworth wrote in news:ukmole-
:

I have a buzzer on the control panel but it's only for 'ignition on' -
can I add the overheat warning into that circuit?



Of course! Yanmar even has them! No boat should be without overtemp
alarms....but you knew that, right?

Look in your Yanmar manual. That SAME buzzer is supposed to blast away if
the engine overheats! You may just have a bad sensor, or some idiot
removed it because he didn't like to hear it warning him his engine was
overheating....

Which Yanmar do you have that DOESN'T have a high temperature alarm LIGHT?

If it's got a light, you can easily add a loud alarm to it by paralleling
that light with an electronic siren module from any Radio Shack store.

I can't find any Yanmars without overtemp alarm circuits.....

I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.

Thanks Larry!

--
Molesworth

--
http://www.stcustards.free-online.co.uk/

On Thu, 18 Sep 2008 16:48:45 -0500, Molesworth
wrote:

I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.

You should probably take the head to a machine shop and have it
checked for warping and cracks.

In article ,
says...
In article ,
Larry wrote:

Molesworth wrote in news:ukmole-
:

I have a buzzer on the control panel but it's only for 'ignition on' -
can I add the overheat warning into that circuit?



Of course! Yanmar even has them! No boat should be without overtemp
alarms....but you knew that, right?

Look in your Yanmar manual. That SAME buzzer is supposed to blast away if
the engine overheats! You may just have a bad sensor, or some idiot
removed it because he didn't like to hear it warning him his engine was
overheating....

Which Yanmar do you have that DOESN'T have a high temperature alarm LIGHT?

If it's got a light, you can easily add a loud alarm to it by paralleling
that light with an electronic siren module from any Radio Shack store.

I can't find any Yanmars without overtemp alarm circuits.....

I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.

Thanks Larry!

--
Molesworth


What model Yanmar do you have? Larry is correct that all of the smaller
Yanmars commonly used in yachts have a warning system - both low oil
pressure and high water temperature. The Yanmar panel has warning lights
and a warning buzzer.

--
Cheers,

Bruce in Bangkok
(pbaige125atgmaildotcom)

Bruce in Bangkok wrote:
In article ,
says...
In article ,
Larry wrote:

Molesworth wrote in news:ukmole-
:

I have a buzzer on the control panel but it's only for 'ignition on' -
can I add the overheat warning into that circuit?


Of course! Yanmar even has them! No boat should be without overtemp
alarms....but you knew that, right?

Look in your Yanmar manual. That SAME buzzer is supposed to blast away if
the engine overheats! You may just have a bad sensor, or some idiot
removed it because he didn't like to hear it warning him his engine was
overheating....

Which Yanmar do you have that DOESN'T have a high temperature alarm LIGHT?

If it's got a light, you can easily add a loud alarm to it by paralleling
that light with an electronic siren module from any Radio Shack store.

I can't find any Yanmars without overtemp alarm circuits.....
I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.

Thanks Larry!

--
Molesworth


What model Yanmar do you have? Larry is correct that all of the smaller
Yanmars commonly used in yachts have a warning system - both low oil
pressure and high water temperature. The Yanmar panel has warning lights
and a warning buzzer.

In addition, many Yanmars have several places where you can add a sensor
into the water system. You can have both the buzzer and an analog temp
gauge. I added gauges so I can watch the temp go up as it warms up and
even if the fridge goes on. I get quick feedback when a belt breaks,
since the buzzer doesn't trip until about 190, but the normal temp is
about 170. The only downside is that my wife has decided that 180 is
"too hot" and she starts to throttle back when I'd rather be running
closer to the design RPM.

In article ,
Bruce in Bangkok wrote:

In article ,
says...
In article ,
Larry wrote:

Molesworth wrote in news:ukmole-
:

I have a buzzer on the control panel but it's only for 'ignition on' -
can I add the overheat warning into that circuit?



Of course! Yanmar even has them! No boat should be without overtemp
alarms....but you knew that, right?

Look in your Yanmar manual. That SAME buzzer is supposed to blast away
if
the engine overheats! You may just have a bad sensor, or some idiot
removed it because he didn't like to hear it warning him his engine was
overheating....

Which Yanmar do you have that DOESN'T have a high temperature alarm
LIGHT?

If it's got a light, you can easily add a loud alarm to it by paralleling
that light with an electronic siren module from any Radio Shack store.

I can't find any Yanmars without overtemp alarm circuits.....

I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.


What model Yanmar do you have? Larry is correct that all of the smaller
Yanmars commonly used in yachts have a warning system - both low oil
pressure and high water temperature. The Yanmar panel has warning lights
and a warning buzzer.

4JH2E

--

Molesworth

--
http://www.stcustards.free-online.co.uk/

In article ,
Wayne.B wrote:

On Thu, 18 Sep 2008 16:48:45 -0500, Molesworth
wrote:

I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.

You should probably take the head to a machine shop and have it
checked for warping and cracks.

Although I've only got the port side stripped down, I can't see any
leaking from that side of the head. Also, on disassembling the heat
exchanger, coolant ran out, as it did when taking off the water pump, so
it didn't run completely dry (grasping at straws here).

But there is diesel in the oil in the sump.. :-(

--
Molesworth

--
http://www.stcustards.free-online.co.uk/

In article ,
Molesworth wrote:

In article ,
Wayne.B wrote:

On Thu, 18 Sep 2008 16:48:45 -0500, Molesworth
wrote:

I've now got all the manuals and I'll look at the wiring diags. I've got
the heat exchanger and water pump off.. just the inlet man to remove
before I can lift the head.

You should probably take the head to a machine shop and have it
checked for warping and cracks.

Although I've only got the port side stripped down, I can't see any
leaking from that side of the head. Also, on disassembling the heat
exchanger, coolant ran out, as it did when taking off the water pump, so
it didn't run completely dry (grasping at straws here).

But there is diesel in the oil in the sump.. :-(

--
Molesworth

If you have diesel in the LubeOil, then look for a leaky Mechanical
Fuel Pump Diaphram, or a blown seal in the Injector Pump......

--
Bruce in alaska
add path after fast to reply

Bruce in alaska wrote in news:fast-C316E2.08580120092008
@netnews.worldnet.att.net:

But there is diesel in the oil in the sump.. :-(

--
Molesworth

If you have diesel in the LubeOil, then look for a leaky Mechanical
Fuel Pump Diaphram, or a blown seal in the Injector Pump......


How old is this engine? There's always some diesel in the lube oil,
especially in an old engine with loose rings.

If the lube oil RISES....then we have a problem.

Some diesel makes it past the rings, expecially when she's cold and blue
smoking. It's why we change the oil often....

I don't like to just pull the dipstick and look at the level in any diesel.
They all should USE a little oil between changes. But, you can REPLACE the
lube oil with diesel in a perfectly normally working engine...The level
stays relatively constant....not good.