Is 210 too hot? I know the manual says 190 to 210, but they seem to
be on the verge of overheating. I've done the heat exchangers,
intercoolers, impellars and trans cooler and they still run hot. My
idiot light sometimes flickers and flashes indicating to me they are
about to over heat. I'm not sure I totally trust these gauges. Most
of the time the starboard gauges are off by 10 degrees. They seem to
track more closely when I'm running over 20.

Thanks much,

Dan

If you're runining in sal****er, you will want to see if you can get things
cooled down a bit.

Somewhere just above 190 degrees the solids begin coming out of suspension in
sal****er, and there is a risk they will begin clogging up waterjackets, heat
exchangers, etc.

You didn't mention the thermostat in the list of things you had looked at.....

Gould 0738 wrote:

Somewhere just above 190 degrees the solids begin coming out of suspension in
sal****er, and there is a risk they will begin clogging up waterjackets, heat
exchangers, etc.

Not to pick too small a nit but the scale producing minerals in seawater
begin to come out of - solution - around 170 degrees F. Suspended
solids, if any, will eventually come out at any temperature above 32F.

Rick

Not to pick too small a nit but the scale producing minerals in seawater
begin to come out of - solution - around 170 degrees F. Suspended
solids, if any, will eventually come out at any temperature above 32F.

Rick

Well, if they begin coming out at 170, they're *really* coming out at 190. :-)

Gould 0738 wrote:

Well, if they begin coming out at 170, they're *really* coming out at 190. :-)

You got that right! If we let an evaporator go to 180 it will scale up
in just a few hours. I've seen tube bundles scaled so badly that way
they look like they have been dipped in cement.

Rick

Rick wrote in message link.net...
Gould 0738 wrote:

Well, if they begin coming out at 170, they're *really* coming out at 190. :-)

You got that right! If we let an evaporator go to 180 it will scale up
in just a few hours. I've seen tube bundles scaled so badly that way
they look like they have been dipped in cement.

Rick


Thanks for your replies. I have not done the thermostats yet, but
will be doing them this week. This last trip was the first since I
went through both engines cooling systems. Thanks again.

Capt. Dan wrote:

Thanks for your replies. I have not done the thermostats yet, but
will be doing them this week. This last trip was the first since I
went through both engines cooling systems. Thanks again.

Hang on a minute ... Chuck and I were talking about a raw water cooled
engine, one which is cooled directly by seawater. If your engine uses a
heat exchanger to remove heat from the engine's freshwater coolant loop
then follow the manufacturer's recommendations.

Rick

Capt. Dan wrote:
Is 210 too hot? I know the manual says 190 to 210, but they seem to
be on the verge of overheating. I've done the heat exchangers,
intercoolers, impellars and trans cooler and they still run hot. My
idiot light sometimes flickers and flashes indicating to me they are
about to over heat. I'm not sure I totally trust these gauges. Most
of the time the starboard gauges are off by 10 degrees. They seem to
track more closely when I'm running over 20.

Thanks much,

Dan


That "might" be correct Dan depends on what motors you have. "Some"
(not many) of the japanese based diesels have the thermostat on the
inlet side of the block (i.e at the bottom not up the top as usual)
however they maintain the temp sender up at/near the outlet, so yes the
water coming "out" of the top is hotter.

Typically a bottom of block mounted thermostat will happily show
over 200 on the gauge. Before you go punching at clouds it's worth
checking to make sure where they're mounted & that they're in good order.

K