N/R 5 port

[anthony_marquart]

I have been given some advice on the volume of water the cooling head of the N/R 5port flows. One bit of advice was to partially fill up the cavity in the cooling head. I'm thinking about doing this but I have some questions.

- In the cooling head there are areas where the water basically would dwell, and then there are areas where the water actually flows through. Should I fill the "dwell" areas all together? This would not really reduce the VOLUME of water flowing.

- Should I also reduce the area in which the water can actually flow? this would restrict the water flow. and what percentage of decrease should I shoot for?

Thanks...

Or should I just drill a hole in the back of the rudder to bleed off pressure there?

 

[John Knight]

Neither. Fill up the water fitting on the rudder with solder or JB Weld. Drill a 1/16'" hole in it and it likely will be about right. Keep the same amt of cooling inside of the water jacket.

 

[Terry Keeley]

Or get a couple different fittings with different holes and experiment a bit. On my 20 mono I use an 0.020" restrictor all year, flows around 2 on an "old school" flow meter.

Be sure to richen up when you do this tho or you'll hole a piston like my bud Olly!

Here's the 0.010" restrictor I've been running in my SAW boat lately, it's a 4-40 brass set screw:

 

[anthony_marquart]

Is this restrictor in the water line? or under the water fitting in the rudder?,...

Or get a couple different fittings with different holes and experiment a bit. On my 20 mono I use an 0.020" restrictor all year, flows around 2 on an "old school" flow meter.

Be sure to richen up when you do this tho or you'll hole a piston like my bud Olly!

Here's the 0.010" restrictor I've been running in my SAW boat lately, it's a 4-40 brass set screw:

 

[Ron Jefferson]

Or get a couple different fittings with different holes and experiment a bit. On my 20 mono I use an 0.020" restrictor all year, flows around 2 on an "old school" flow meter.

Be sure to richen up when you do this tho or you'll hole a piston like my bud Olly!

Here's the 0.010" restrictor I've been running in my SAW boat lately, it's a 4-40 brass set screw:

Hey Keeley,

Most of these guys wouldn't even recognize that coin. It is a loonie, isn't it? Lol And I don't think the hole in Olly's piston was from lack of water. Way too many "clicks" is what I'm thinking.

Jr.

 

[Terry Keeley]

:lol:

Yup, my mate likes 'em "lean & mean". That's a Canadian 10 peso piece, not! :huh:

Anthony: I tap the fitting on the rudder 4-40 and screw the restrictor into it. The set screws are available at McMaster Carr.

 

[Olly]

Ron

If you remember, I had a piece of weed in the restrictor and the motor got way to HOT.

Olly

 

[Tim Kish]

Ron

If you remember, I had a piece of weed in the restrictor and the motor got way to HOT.

Olly

Translation

You were smoking weed in a restrictor and were getting hot flashes :lol: :lol:

Sorry Olly couldn't resist

 

[Richard Dahlheimer]

Ron

If you remember, I had a piece of weed in the restrictor and the motor got way to HOT.

Olly

Here in MN now the water temp is low 40s for sure. I have been running my .20 hydro with a Frank Orlic water jacket which has less water volume than the stock Nova water jacket. I also have a simple tie wrap on the water line just above the rudder water fitting. I have the tie wrap tightened up, to let just a "trickle" of water exit the jacket. Not very high tech but it works well. For this cold of water, it wont take much water to keep your engine temp safe. I am sure you can also fill the stock water jacket with JB Weld, to just under the inlet and outlet fittings. Richen up the needle before you run the boat. Richard D

 

[Terry Keeley]

:lol: :lol: :lol:

ps: forgot about the weeds...

 

[dwilfong]

I have tried the set screw in the water fitting. But now I use a fuel needle in the water line. Had a K&B remote needle and put it in line. Got one of Boris flow meters and use it to set the flow. Seams the same number for the fuel works for the water. Go figure that one.

David

 

[John Knight]

Ron

If you remember, I had a piece of weed in the restrictor and the motor got way to HOT.

Olly

Here in MN now the water temp is low 40s for sure. I have been running my .20 hydro with a Frank Orlic water jacket which has less water volume than the stock Nova water jacket. I also have a simple tie wrap on the water line just above the rudder water fitting. I have the tie wrap tightened up, to let just a "trickle" of water exit the jacket. Not very high tech but it works well. For this cold of water, it wont take much water to keep your engine temp safe. I am sure you can also fill the stock water jacket with JB Weld, to just under the inlet and outlet fittings. Richen up the needle before you run the boat. Richard D

Sorry Richard, I disagree with putting JB Weld inside the water jacket. You want to restrict the water coming into the boat & engine by reducing the flow BEFORE the engine. You reducing flow inside the water jacket is like throwing craps as hot spots are most likely to form and that is not good. All my NR's have the Orlic head and water jackets but in cooler water they are still too large. In the summer they are about right. But always restrict the water in the incoming line and not inside the engine. Several water inlet fittings can be used with different size holes as noted before. What works as temp control in FLA or SC likely will not work in MN, MI or Canada.

 

[Richard Dahlheimer]

Ron

If you remember, I had a piece of weed in the restrictor and the motor got way to HOT.

Olly

Here in MN now the water temp is low 40s for sure. I have been running my .20 hydro with a Frank Orlic water jacket which has less water volume than the stock Nova water jacket. I also have a simple tie wrap on the water line just above the rudder water fitting. I have the tie wrap tightened up, to let just a "trickle" of water exit the jacket. Not very high tech but it works well. For this cold of water, it wont take much water to keep your engine temp safe. I am sure you can also fill the stock water jacket with JB Weld, to just under the inlet and outlet fittings. Richen up the needle before you run the boat. Richard D

Hello John, i dont think you fully understand my post. I am restricting the water before the engine with a tie wrap above the water fitting, of the rudder. The JB Weld in the stock water jacket will decrease water volume : similar to Orlic jacket. Richard D

Sorry Richard, I disagree with putting JB Weld inside the water jacket. You want to restrict the water coming into the boat & engine by reducing the flow BEFORE the engine. You reducing flow inside the water jacket is like throwing craps as hot spots are most likely to form and that is not good. All my NR's have the Orlic head and water jackets but in cooler water they are still too large. In the summer they are about right. But always restrict the water in the incoming line and not inside the engine. Several water inlet fittings can be used with different size holes as noted before. What works as temp control in FLA or SC likely will not work in MN, MI or Canada.

 

[Terry Keeley]

Ron

If you remember, I had a piece of weed in the restrictor and the motor got way to HOT.

Olly

Here in MN now the water temp is low 40s for sure. I have been running my .20 hydro with a Frank Orlic water jacket which has less water volume than the stock Nova water jacket. I also have a simple tie wrap on the water line just above the rudder water fitting. I have the tie wrap tightened up, to let just a "trickle" of water exit the jacket. Not very high tech but it works well. For this cold of water, it wont take much water to keep your engine temp safe. I am sure you can also fill the stock water jacket with JB Weld, to just under the inlet and outlet fittings. Richen up the needle before you run the boat. Richard D

Sorry Richard, I disagree with putting JB Weld inside the water jacket. You want to restrict the water coming into the boat & engine by reducing the flow BEFORE the engine. You reducing flow inside the water jacket is like throwing craps as hot spots are most likely to form and that is not good. All my NR's have the Orlic head and water jackets but in cooler water they are still too large. In the summer they are about right. But always restrict the water in the incoming line and not inside the engine. Several water inlet fittings can be used with different size holes as noted before. What works as temp control in FLA or SC likely will not work in MN, MI or Canada.

Was always amazed at how warm your southern lakes get in the summer, haven't measured but bet some would be 90F or so.

Lakes up north stay fairly cool all year and it's real easy to over cool things...

 

[Ted buckley]

Neither. Fill up the water fitting on the rudder with solder or JB Weld. Drill a 1/16'" hole in it and it likely will be about right. Keep the same amt of cooling inside of the water jacket.

I think I like John's Idea the best.. I've tried all the others - especially with the tie wraps, and you can just never get the tie wraps just right. I think JB weld in the fitting will be my next attempt. You can always make the dia. of the hole bigger as needed - and also, you can remove the JB weld from the fitting - with some heat if you don't want it anymore..

 

[Jerry Wyss]

Very intresting subject, one that I have been toying with for a while. The "before" the water cooling head pressure& volume reduction or "after" the head is basically the two camps. Also the stock full size waterway in the head or a custom head with reduced waterway are also differing factors.

The "before" the head reduction would create very little pressure in the head waterway, unless in the event that the water flashes to a boil.

The "after" the head waterway reduction could raise the water pressure in the head. The upside to that is that if it was enough pressure it could actually raise the boiling point of the water beyond 212*. Now I really don't think that a water rudder or the other methods of picking up water are going to raise the water column very high but it could be enough to make things more efficient.

Both methods are subject to possible plugging of the reduction orifice and we all know what means. With my testing JB Weld in the head is more susceptible to plugging the after head reduction. Epoxy in water seems to develope a softening of the surface, and with the heating, sometimes super heating, it can start to break down or seperate from the aluminum head.

So with me I favor the custom waterway in the head (all metal) along with the after head volume reduction.

2 cents is all it's worth

 

[Ted buckley]

Very intresting subject, one that I have been toying with for a while. The "before" the water cooling head pressure& volume reduction or "after" the head is basically the two camps. Also the stock full size waterway in the head or a custom head with reduced waterway are also differing factors.

The "before" the head reduction would create very little pressure in the head waterway, unless in the event that the water flashes to a boil.

The "after" the head waterway reduction could raise the water pressure in the head. The upside to that is that if it was enough pressure it could actually raise the boiling point of the water beyond 212*. Now I really don't think that a water rudder or the other methods of picking up water are going to raise the water column very high but it could be enough to make things more efficient.

Both methods are subject to possible plugging of the reduction orifice and we all know what means. With my testing JB Weld in the head is more susceptible to plugging the after head reduction. Epoxy in water seems to develope a softening of the surface, and with the heating, sometimes super heating, it can start to break down or seperate from the aluminum head.

So with me I favor the custom waterway in the head (all metal) along with the after head volume reduction.

2 cents is all it's worth

Jerry, Of course I don't use h2o in my .12 period - Cause I like to use YOUR Cool-to-fuel method, but on my .21, I've been using the After Head reduction method in the form of a fuel line w/ brass tubing/Jb weld w/1-16" drill bit hole.. It seems to work pretty well, but I've been starting to consider pressure now and not muss with the Water jacket period. The temp's I've been experiencing have been between 180-220 degrees, but varies with our cold Minnesota water. I was thinking about John Knights Idea for most of the summer now, and think maybe it's worth a try.

 

[John Knight]

Richard,

I did misunderstand you earlier. I have used the tie wrap many times as the southern temps vary a great deal during the year. It is simple to do. If you have flow meter you can regulate it quite well. I have used the OS manual needle in the cooling line too but don't like the flopping around of it. Just use what works for each of you. But many of the stock water jackets are too large and cools too much for the most efficient running.

The summer months we have lake water temp in the mid to high 80's easily. We see temp swings from the low 50's to close to 90 during the year. A real challenge to keep on top of it.

 

[anthony_marquart]

Well it's cold here... I plugges the water fitting with JB weld and drilled a 0.050 hole in it. I think what I'm going to end up doing is put a set screw in the water outlet of the head to block it,.. then put a 0.05 hole in the top of the water jacket. This will slow the flow, keep the pressure,.. etc,..

your thoughts?

 

[dave roach]

Anthony

Get a os in line needle and put it back by the rudder and you can control the water to the Engine.

Dave Roach