160 or 140 Thermostat?
 

It seems most new boats have a 160 thermostat these days. I have a '93
Mercruiser 4.3LX. Can I use the 160 thermostat? I boat exclusively in
fresh water. I want to get the cleaner combustion that the higher temps
give.

160 or 140 Thermostat?
 

On Mon, 23 Feb 2004 20:10:04 +0000, Geoff 93 RRC wrote:

It seems most new boats have a 160 thermostat these days. I have a '93
Mercruiser 4.3LX. Can I use the 160 thermostat? I boat exclusively in
fresh water. I want to get the cleaner combustion that the higher temps
give.

Raw-water cooled or FWC (with heat exchanger)? I'd say if FWC, definitely
go with 160. Raw-water, I donno - I guess you should be OK if you're in
fresh water...

Lloyd Sumpter
"Far Cove" Catalina 36

160 or 140 Thermostat?
 

On Mon, 23 Feb 2004 20:10:04 GMT, "Geoff 93 RRC"
wrote:
It seems most new boats have a 160 thermostat these days. I have a '93
Mercruiser 4.3LX. Can I use the 160 thermostat? I boat exclusively in
fresh water. I want to get the cleaner combustion that the higher temps
give.
==============================================

160 is OK for fresh water usage but not for salt water.

160 or 140 Thermostat?
 

On Mon, 23 Feb 2004 20:10:04 GMT, "Geoff 93 RRC"
wrote:

It seems most new boats have a 160 thermostat these days. I have a '93
Mercruiser 4.3LX. Can I use the 160 thermostat? I boat exclusively in
fresh water. I want to get the cleaner combustion that the higher temps
give.

Ok, I've a different opinion.

I prefer to run a little cooler thermostat with a hotter plug. I've
done this on my antigue trucks and this technique works great.

If you are looking for power and clean combustion, a hotter plug is
always the best choice over fooling around with the thermostat. You
have to remember that the reason you have a thermostat is to maintain
a constant temperature on the block for expansion/contraction reasons
- not for combustion. Combustion is strictly the pervue of how hot
the spark is.

Curiosity question - raw water cooled or fresh.

Later,

Tom
S. Woodstock, CT
----------

Basic Fishing Program:

10 - Fish
20 - Eat
30 - Sleep
40 - Goto 10

160 or 140 Thermostat?
 

"Wayne.B" wrote in message
...

==============================================

160 is OK for fresh water usage but not for salt water.


Why is that?

Thanks,
Rich

160 or 140 Thermostat?
 

"Rich" wrote in message
. com...

"Wayne.B" wrote in message
...

==============================================

160 is OK for fresh water usage but not for salt water.


Why is that?

Thanks,
Rich



Salt will have a bigger tendency to plate the inside of the engine with the
higher temps thermostat.
Bill

160 or 140 Thermostat?
 

"Short Wave Sportfishing" wrote in message
...
On Mon, 23 Feb 2004 20:10:04 GMT, "Geoff 93 RRC"
wrote:

If you are looking for power and clean combustion, a hotter plug is
always the best choice

Actually, the heat range of the plug only refers to the plugs ability to
transfer heat from the plug to the head. A hot plug is one that that the
tip retains more heat, a cold plug transfers heat quickly. When driving,
the tips of the spark plugs are heated to incandescence. The heat must
travel from the tip through the shell and ultimately into the water jacket
of the cooling system. If the plug is too cold it will foul, if its too hot
you will get detonation, that is, the fuel will ignite before the timed
spark -- and you can blown a hole through the piston!

The octane rating of the fuel and compression ratio will determine the
correct heat range plug to use. Unless you have modified the engine, stick
to the manufacturers recommendation.

Rich

160 or 140 Thermostat?
 

"Short Wave Sportfishing" wrote in message
...
On Mon, 23 Feb 2004 20:10:04 GMT, "Geoff 93 RRC"
wrote:

If you are looking for power and clean combustion, a hotter plug is
always the best choice

Actually, the heat range of the plug only refers to the plugs ability to
transfer heat from the plug to the head. A hot plug is one that that the
tip retains more heat, a cold plug transfers heat quickly. When driving,
the tips of the spark plugs are heated to incandescence. The heat must
travel from the tip through the shell and ultimately into the water jacket
of the cooling system. If the plug is too cold it will foul, if its too hot
you will get detonation, that is, the fuel will ignite before the timed
spark -- and you can blown a hole through the piston!

The octane rating of the fuel and compression ratio will determine the
correct heat range plug to use. Unless you have modified the engine, stick
to the manufacturers recommendation.

Rich

160 or 140 Thermostat?
 

In article ,
says...
It seems most new boats have a 160 thermostat these days. I have a '93
Mercruiser 4.3LX. Can I use the 160 thermostat? I boat exclusively in
fresh water. I want to get the cleaner combustion that the higher temps
give.

The manufacturers only distinguish between fresh and raw water cooled
engines. 140 is recommended in raw water, 160 for FWC.

jps

160 or 140 Thermostat?
 

On Tue, 24 Feb 2004 00:00:37 GMT, "Rich" wrote:


"Short Wave Sportfishing" wrote in message
.. .
On Mon, 23 Feb 2004 20:10:04 GMT, "Geoff 93 RRC"
wrote:

If you are looking for power and clean combustion, a hotter plug is
always the best choice

Actually, the heat range of the plug only refers to the plugs ability to
transfer heat from the plug to the head. A hot plug is one that that the
tip retains more heat, a cold plug transfers heat quickly. When driving,
the tips of the spark plugs are heated to incandescence. The heat must
travel from the tip through the shell and ultimately into the water jacket
of the cooling system. If the plug is too cold it will foul, if its too hot
you will get detonation, that is, the fuel will ignite before the timed
spark -- and you can blown a hole through the piston!

It is my understanding that a "hot" plug is aimed more towards keeping
heat available to burn off deposits quicker and help with a cleaner,
quicker burn when the fuel/air mixture is ignited. It is also my
understanding that engine manufacturers allow for a range of types of
hot to cold plugs to adjust for varying conditions like altitude,
emissions requirements and other issues.

I have adjusted plugs for hot/cold on high performance engines because
of the varying temperatures in different cylinders - all within a
range of course but all on the same engine.

Perhaps I should have said Hottest Recommended Plug?

Later,

Tom
S. Woodstock, CT
----------

Basic Fishing Program:

10 - Fish
20 - Eat
30 - Sleep
40 - Goto 10