I just joined this group and have a dilema to present:

My boat has a large engine room and I want to add a genset to it. BUT
it must be diesel as I dont want any gasoline aboard. I can buy a new
marine diesel gen set with warer cooling for $7,000 or so. I dont have
that kind of money to spend. But I can buy a new diesel, AIR COOLED,
getset for under $1000. With the gen set in the engine room I will
either have to supply a MINIMUM (probably more) of 1000 CFM of cool air
and exhaust it as well. This is not altogether too dificult, BUT that
air I am supplying will be SALT air and will promote corrosion in the
new gen set, I am sure.

So I am wondering about the possibility of converting the air cooled
diesel to a water cooled diesel with a salt to fresh water heat
exchanger. I read somewhere once that someone did this by coiling
copper pipe around the head of the engine for the fresh water part and
used a wet exhaust to cool the exhaust. But with no details of how the
fresh water cooling was actually constructed on the engine, and my
limited imagination in this area, I dont see how it could work. I
think it would take more than cooling the head alone.

Does anyone have any ideas along these lines??

jim.isbell wrote:
I just joined this group and have a dilema to present:

My boat has a large engine room and I want to add a genset to it. BUT
it must be diesel as I dont want any gasoline aboard. I can buy a new
marine diesel gen set with warer cooling for $7,000 or so. I dont have
that kind of money to spend. But I can buy a new diesel, AIR COOLED,
getset for under $1000. With the gen set in the engine room I will
either have to supply a MINIMUM (probably more) of 1000 CFM of cool air
and exhaust it as well. This is not altogether too dificult, BUT that
air I am supplying will be SALT air and will promote corrosion in the
new gen set, I am sure.

So I am wondering about the possibility of converting the air cooled
diesel to a water cooled diesel with a salt to fresh water heat
exchanger. I read somewhere once that someone did this by coiling
copper pipe around the head of the engine for the fresh water part and
used a wet exhaust to cool the exhaust. But with no details of how the
fresh water cooling was actually constructed on the engine, and my
limited imagination in this area, I dont see how it could work. I
think it would take more than cooling the head alone.

Does anyone have any ideas along these lines??

I wouldn't waste my time on this, it's not worth it, your just looking
for trouble and the gen set will not be CG approved. If you have a
problem, fire, CO gas, ect, your in trouble, your insurance won't cover
it. And the boat will never pass a survey.

On 27 Jul 2006 09:20:50 -0700, "Capt John"
wrote:

I wouldn't waste my time on this, it's not worth it, your just looking
for trouble and the gen set will not be CG approved. If you have a
problem, fire, CO gas, ect, your in trouble, your insurance won't cover
it. And the boat will never pass a survey.

I agree. Probably your best bet is to find a good used "takeout".
Check with one of your local Kohler or Onan dealers, they may have
some laying around. Also check on EBAY.

You don't want gasoline because it is too dangerous....and you want to jury
rig cooling of a stay ashore generator???? Must be a troll.
"jim.isbell" wrote in message
oups.com...
I just joined this group and have a dilema to present:

My boat has a large engine room and I want to add a genset to it. BUT
it must be diesel as I dont want any gasoline aboard. I can buy a new
marine diesel gen set with warer cooling for $7,000 or so. I dont have
that kind of money to spend. But I can buy a new diesel, AIR COOLED,
getset for under $1000. With the gen set in the engine room I will
either have to supply a MINIMUM (probably more) of 1000 CFM of cool air
and exhaust it as well. This is not altogether too dificult, BUT that
air I am supplying will be SALT air and will promote corrosion in the
new gen set, I am sure.

So I am wondering about the possibility of converting the air cooled
diesel to a water cooled diesel with a salt to fresh water heat
exchanger. I read somewhere once that someone did this by coiling
copper pipe around the head of the engine for the fresh water part and
used a wet exhaust to cool the exhaust. But with no details of how the
fresh water cooling was actually constructed on the engine, and my
limited imagination in this area, I dont see how it could work. I
think it would take more than cooling the head alone.

Does anyone have any ideas along these lines??

No, not a troll. And NO, I dont want to "jurry rig."

I want to do it right the first time. I see no reason why ducting air
to an air cooled device is jurry rigging. After all we duct sea water
to a fresh water cooled engine to cool the fresh water and we dont call
that "jurry rigged". If any thing is a Rube Goldperg design, fresh
water cooled engines are!!!

Sure, if one does not prepare for all the challanges, it would be jurry
rigged. With propper sensing on engines we prevent destructive
failures. Why cant we assume the same for an air cooled system? I
would use temperature sensing to make sure there was no fire hazard
etc.

Dave W wrote:
You don't want gasoline because it is too dangerous....and you want to jury
rig cooling of a stay ashore generator???? Must be a troll.
"jim.isbell" wrote in message
oups.com...
I just joined this group and have a dilema to present:

My boat has a large engine room and I want to add a genset to it. BUT
it must be diesel as I dont want any gasoline aboard. I can buy a new
marine diesel gen set with warer cooling for $7,000 or so. I dont have
that kind of money to spend. But I can buy a new diesel, AIR COOLED,
getset for under $1000. With the gen set in the engine room I will
either have to supply a MINIMUM (probably more) of 1000 CFM of cool air
and exhaust it as well. This is not altogether too dificult, BUT that
air I am supplying will be SALT air and will promote corrosion in the
new gen set, I am sure.

So I am wondering about the possibility of converting the air cooled
diesel to a water cooled diesel with a salt to fresh water heat
exchanger. I read somewhere once that someone did this by coiling
copper pipe around the head of the engine for the fresh water part and
used a wet exhaust to cool the exhaust. But with no details of how the
fresh water cooling was actually constructed on the engine, and my
limited imagination in this area, I dont see how it could work. I
think it would take more than cooling the head alone.

Does anyone have any ideas along these lines??

Jim,

Sorry, but changing the mode of cooling for an engine without proper
engineering *is* jury rigging. Not at all the same as just using a
water-to-water heat exchanger. If you're worried about "salt" air, and
you're running in cold water, put a de-mister coil in the air duct and
pipe sea water through it chill it and pull the moisture out of the air.
Now that's a Rube'd device that would actually work. Bear in mind
though that by the time you buy all the required equipment to make the
aircooled unit functional and long-lived, you'll have a bunch more into
it than the $1K, and you'll have a less fuel-efficient unit.

Keith Hughes

jim.isbell wrote:
No, not a troll. And NO, I dont want to "jurry rig."

I want to do it right the first time. I see no reason why ducting air
to an air cooled device is jurry rigging. After all we duct sea water
to a fresh water cooled engine to cool the fresh water and we dont call
that "jurry rigged". If any thing is a Rube Goldperg design, fresh
water cooled engines are!!!

Sure, if one does not prepare for all the challanges, it would be jurry
rigged. With propper sensing on engines we prevent destructive
failures. Why cant we assume the same for an air cooled system? I
would use temperature sensing to make sure there was no fire hazard
etc.

Dave W wrote:

You don't want gasoline because it is too dangerous....and you want to jury
rig cooling of a stay ashore generator???? Must be a troll.
"jim.isbell" wrote in message
groups.com...

I just joined this group and have a dilema to present:

My boat has a large engine room and I want to add a genset to it. BUT
it must be diesel as I dont want any gasoline aboard. I can buy a new
marine diesel gen set with warer cooling for $7,000 or so. I dont have
that kind of money to spend. But I can buy a new diesel, AIR COOLED,
getset for under $1000. With the gen set in the engine room I will
either have to supply a MINIMUM (probably more) of 1000 CFM of cool air
and exhaust it as well. This is not altogether too dificult, BUT that
air I am supplying will be SALT air and will promote corrosion in the
new gen set, I am sure.

So I am wondering about the possibility of converting the air cooled
diesel to a water cooled diesel with a salt to fresh water heat
exchanger. I read somewhere once that someone did this by coiling
copper pipe around the head of the engine for the fresh water part and
used a wet exhaust to cool the exhaust. But with no details of how the
fresh water cooling was actually constructed on the engine, and my
limited imagination in this area, I dont see how it could work. I
think it would take more than cooling the head alone.

Does anyone have any ideas along these lines??

Keith Hughes wrote:
Jim,

Sorry, but changing the mode of cooling for an engine without proper
engineering *is* jury rigging.

I didnt say I wanted to do it "without proper engineering."

That is why I am here, to get information on how to properly engineer
it. I am an engineer so with proper input I think this can be done.

As you say, it may not be economical, but to reject it out of hand is
shortsighted.

I always like to point out to young engineers that if we didnt try what
couldnt be done, nothing would ever be accomplished. Almost any
engineering project has never been done before or it wouldnt be in the
engineering department, the technicians in the lab would have looked it
up and done it by now.

jim.isbell wrote:
Keith Hughes wrote:

Jim,

Sorry, but changing the mode of cooling for an engine without proper
engineering *is* jury rigging.


I didnt say I wanted to do it "without proper engineering."

OK, but 'wrapping copper tubing around the cylinders' doesn't sound like
an approach resulting from much engineering analysis.

That is why I am here, to get information on how to properly engineer
it. I am an engineer so with proper input I think this can be done.

Well then, surely you must know that you first need the designed
combustion chamber temperature range and the thermal conduction profile
for the cylinder sleeve (top to bottom), to properly size the multiple,
vertically segmented, cooling loops you'll require. You could estimate
the vertical temperature cline by analyzing the relative fin surface
areas, air flow rates, and standard thermal conduction value (F sub r, U
sub L as ASHRAE defines it) and the emissivity of the fin material. And
that just gets you the info you need to design the heat exchange
process. You need to go through the same exercise with the copper
tubing with the bonding method, heat transfer characteristics, mass flow
requirements, baffling to ensure turbulent flow, etc., etc. Not a
trivial exercise.


As you say, it may not be economical, but to reject it out of hand is
shortsighted.

As you seem to have rejected, out of hand as you say, the most simple
way of achieving your stated goal? I.e., not air cooling with "salt"
air. Properly trapped (i.e. collection drain) demisters are the
standard method for achieving these results. Used all the time to pull
moisture from ductwork.

I always like to point out to young engineers that if we didnt try what
couldnt be done, nothing would ever be accomplished.

You might also want to point out that trying to create novel designs and
implementations when existing designs *meet all customer requirements*
results in nothing but higher development costs and, typically,
unnecessary process complexity. This, IME, is the biggest failing of
most engineers (excepting R&D of course).

And, I might point out, this thread epitomizes that situation; trying to
redesign the end point of the process (i.e. the engine) instead of
addressing the problem earlier in the process (i.e. the cooling air
supply) where it can be solved easier, cheaper, and with less complexity.

Almost any
engineering project has never been done before or it wouldnt be in the
engineering department, the technicians in the lab would have looked it
up and done it by now.

Well, sorry but that's just ridiculous. Virtually all day to day
engineering projects are varying implementations of basic
systems/processes that are done all the time. The vast majority of
engineers are not involved in R&D work; they're doing practical process
applications using basic engineering principles. I'm not trivializing
the Engineering process. The most difficult engineering exercise, IME,
is taking an existing process or piece of equipment and implementing
that process or equipment into a specific/unique application and
achieving a result that is timely rugged, efficient, cost-effective, and
meets the specific needs of the end user. If you can do all of those
five, you're a damn fine engineer.

Keith Hughes

"jim.isbell" wrote in message
ups.com...
No, not a troll. And NO, I dont want to "jurry rig."

No, but you want to "warer cool".

Judge not, lest ye be judged.
Sounds like a troll to me.

You could try this. A fan sucking from a long duct inside the hull.
If the hull is steel or aluminum, it would be quite effectively cooled
air from the sea water. The duct plays over the cylinder then exhaust
manifold.

Brian Whatcott.


On 28 Jul 2006 07:43:15 -0700, "jim.isbell"
wrote:

No, not a troll. And NO, I dont want to "jurry rig."

I want to do it right the first time. I see no reason why ducting air
to an air cooled device is jurry rigging. After all we duct sea water
to a fresh water cooled engine to cool the fresh water and we dont call
that "jurry rigged". If any thing is a Rube Goldperg design, fresh
water cooled engines are!!!

Sure, if one does not prepare for all the challanges, it would be jurry
rigged. With propper sensing on engines we prevent destructive
failures. Why cant we assume the same for an air cooled system? I
would use temperature sensing to make sure there was no fire hazard
etc.

Dave W wrote:
You don't want gasoline because it is too dangerous....and you want to jury
rig cooling of a stay ashore generator???? Must be a troll.
"jim.isbell" wrote in message
oups.com...
I just joined this group and have a dilema to present:

My boat has a large engine room and I want to add a genset to it. BUT
it must be diesel as I dont want any gasoline aboard. I can buy a new
marine diesel gen set with warer cooling for $7,000 or so. I dont have
that kind of money to spend. But I can buy a new diesel, AIR COOLED,
getset for under $1000. With the gen set in the engine room I will
either have to supply a MINIMUM (probably more) of 1000 CFM of cool air
and exhaust it as well. This is not altogether too dificult, BUT that
air I am supplying will be SALT air and will promote corrosion in the
new gen set, I am sure.

So I am wondering about the possibility of converting the air cooled
diesel to a water cooled diesel with a salt to fresh water heat
exchanger. I read somewhere once that someone did this by coiling
copper pipe around the head of the engine for the fresh water part and
used a wet exhaust to cool the exhaust. But with no details of how the
fresh water cooling was actually constructed on the engine, and my
limited imagination in this area, I dont see how it could work. I
think it would take more than cooling the head alone.

Does anyone have any ideas along these lines??