The Harrison Racing Outboards - Legendary Birmingham Metal Products Alky Outboards

[Bill Van Steenwyk]

John:

Go to a thread entitled "water injection questions from the Quincy forum". You can find it under Technical Discussion Topic on BRF, page 6, date 1/21/07. Those comments/information might be helpful to you. The original idea seems to have orginated in the 60's because of research being done to try to increase power on early jet engines on commercial aircraft for takeoff. When injecting a water/alcohol mix into the engine, in front of the compressor blades I believe, they found that the noise level was also affected greatly, namely it quietened the engine down considerably. The reason was that the water/alcohol mix cooled the incoming air and also the combustion process somewhat and that changed the wave form distance in the sound waves being emitted by the engine. As you probably know, changing the distance the sound wave travels from the reflecting point on an exhaust system also changes the power band, and from there it was a short step for people who became aware of that research to try it on exaust systems on 2 strokes, first with megaphone exaust and then on expansion chambers. This research was widely publicized at that time, and I remember calling Harry ZAK about it. This was about the same time that Christner put water injection on the Flatheads and Harry also used it on his first ZAK pipes as they did not slide and he needed a way to change the powerband, which that accomplished. I really don't know who was first and don't think it makes much difference, but that was the time frame involved, so it is not a new concept, and as a lot of other things that speed freaks pick up, came from the aviation industry.

[John (Taylor) Gabrowski]

I kinda walked over to the table with this kit sitting there and asked myself the question if this was some kind of fancy fuel injection setup for some snowmobile engine that blasted something exotic before or after the carbs to make the engine act as if there was an afterburner tied to it and with that I questioned the guy, the seller and he said "you never seen a water injection system for 2 stroke racing pipes"? My answer was "nothing like that"! He said well, its dated, its new, its basically all there, just the wiring harness missing and he thought the price was right! I looked at the tag in shock, used my pocket change (and I do mean coins, not bills) and just paid the man, his first sale that afternoon, put it in a bag for me and I went and locked it in the trunk of the car! Get a load of this!

[John (Taylor) Gabrowski]

Sorry about that!

[John (Taylor) Gabrowski]

Last Picture

[Bill Van Steenwyk]

John:

The two items with the hose outlets on them look to be electrically operated solenoid valves, which would give a positive opening and closing of the water path to the exaust system when actuated, eliminating the problem with the suction of the pipes at high RPM sucking water from the bottle, resulting in the problems I mentioned on the other thread causing piston damage. I would stongly suggest if you plan on trying the system on anything that you use them in line to the exaust as they will eliminate a lot of potential problems with this type of system, including engine damage if the water would be sucked back into a cylinder because it was getting into the system when not wanted. Looks like a very professional system that was probably designed specifically for something, perhaps a PWC as Sam mentioned.

[John (Taylor) Gabrowski]

Unfortunately the picture does not show the 2 discharge nozzles deep in one pocket of the foam packaging that also have a kind of overpressure? return circuit to them.

What ever the discharge or transfer lines were made of are also missing from their section of the packaging but their size seems logical to match.

What bothers me is the large 12 volt DC black pressurizing pump that sits there as well as that control box. There was no wiring or liquid circuit diagram so it leaves one to ask if the pump was used to precharge? or instantly pressurize upon triggering? Do the bottle contents come from another liquid source for a electronically controlled burst to the pipes at some given pressure and is it meant to refill itself but from what when its for a snowmo sled, I assume as the seller only said 2 stroke?

The bottle is thick high impact plastic with a pressure cap. That control box and solinoid system may have some sensor features to them? I looked at my Quincy Flathead water injection diagrams sheets with its single 12 volt solinoid valve that when triggered delivered pressurized water from the gearcase outflow to 4 nozzles at once, each aimed straight backward from the exhausts with the nozzles located on shoulders on the exhaust elbos. I suppose with Quincy 3rd generation bell stacks there was little chance the water was going to get sucked back once the power was cut? When I tried that engine on rebuild I tooled with the water injection a bit but I was not satisfied with the water output or pressure then. It all seemed weak. With this system perhaps there is something more automatic and way higher pressure about it given its complexity?

Would you, Mark 75H or any reader have some kind of schematic that shows the water and power circuitry to a basic bottled water stack injection system similar to this? It would give some guidance in figuring out how it might work leading to test bedding the thing to see how it actually does work without first installing it on any engine and prehaps damaging things going that route when it can be found out otherwise?

It is a very interesting system. I ask myself why some one did not use it as there are no marks on the connectors (still bagged) or components that would show it ever was hooked up and ever tried? Maybe it already scared off somebody for some reasons not yet revealed? When you get something this inexpensively its like something too good to be true? The rule is that it is generally that. (too good to be true)

Here is to hoping for more info.

[John (Taylor) Gabrowski]

Bill wrote a technical article about water injecting pipes. I copied it over here just to refocus what has been said to figure out this system for its pros, cons and potential uses, missuses and problems.

advantage and disadvantage of water injection in pipes

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As Sam has mentioned in his earlier post the injection of water into the exhaust system cools the exaust gas and makes the engine think the pipe is longer than it really is while the water is being injected, giving you more bottom end/torque allowing you to pull a larger prop through the tough part of the power band, which is just when the boat breaks over on plane and puts a load on the engine. Larger prop at peak rpm equals more speed. I set a Kilo record in the mid 80'd at almost 91 MPH with a Yamato Model 80 on fuel with ONE 25mm CARB, using water injection as an aid to keep going after breaking over on plane and continue on with a larger than usual prop, thus achieving a speed that would not normally have been possible.

We used a ordinary aftermarket winshield washer system purchased at an auto supply store consisting of a plastic container that held about a quart of water and had a 12 volt motor mounted in the bottom of the container. Real neat and tidy and easy to mount. Ran two hoses, one to each collector pipe for each expansion chamber with a capability of inserting bing carb jets in the stand off pipe brazed in the collector so as to adjust the amount of water injected when you pushed the button. Used a small 12V battery from a portable VCR that weighed about a pound so very small and lightweight for power.

The Disadvantage: you needed a very good check valve in the line or two was better for safety as the motor would have a tendency at high RPM to suck water from the tank whether the switch was activated or not because of suction developed by the expansion chambers. In addition to slowing the motor down if this got into the pipe at the wrong time, you could actually suck the water vapor into the cylinders where it turned to steam immediately and the additional pressure of the steam plus normal combustion would crack pistons like walnuts. We destroyed several pistons before Harry ZAK finally figured out what was happening and got some decent check valves in the line to stop the problem.

Another disadvantage was that if you had it hooked up all the time, the tendency was to use it too often, sometimes mistaking a non-connected engine problem with loading the engine by thinking you had a little too large a prop on and trying to get the motor going when that was not the problem at all.

Short and sweet, for the right reasons it was good to have but easy to overuse if you weren't careful, and could be hard on the engine as mentioned.

[epugh66]

On the topic of sleaves. On our Yamato 250's, we just put the half block in the oven, let it bake till the sleave fell out. Had the new sleave in the freezer, reheated the block, dropped the new sleave in, making sure to align it fast. Once it clamps down, it's start all over. After that, have the block bored and smooth out the ports.

The problem with bottle water injection systems is, you eventually run out of water. We used two systems.

One was based on picking water up off the sponson bottom and controling flow with a 90 degree ball valve. Casting for ball valve mount was made by Birmingham Metal Products, you could also use ZIP ties, but that wasn't Kay's style. Even at just on plane speed, it provided enough squirt to boost a 250.

The other used a water tank from an '80's Mazda car. Allyn Stevens buily a tester to test the output and PSI of all the water pumps he could find( really, he did). The two down sides was you had to carry a battery(and charge it) and it would wind up empty. My solution to the empty bottle syndrom was to tap into my cooling water intake to refill. I put an over flow hose out the side of the boat for excess.

Yamato put an end to all that nonsense by installing reeds.

[John (Taylor) Gabrowski]

I did some asking around this morning about what was going on with these kinds of bottled injection systems in SnowMo years past.

It turns out that this stuff was being adapted for snowmo drag racing in particular for running unlimited classes for 1/8 th mile drags on grass and snow/ice. No one apparently ever used it for oval racing.

Some used this kind of stuff to inject fuels like nitro, water & methanol mixes into the carbs air/fuel streams (before? or after?the carb not known) and using knock sensors to deal with timing issues when the system was triggered on. On SnowJets Thunderjet 440s systems like these were used with the Yamaha mechanical fuel injection to deal with some of its shortcomings which were apparently frequent piston meltdowns problems.

Some injected water into the expansion chamber racing pipes and the bottle was the ideal size to handle the length of the typical drag races.

Weirder still was some racers tried injecting hydrogen peroxide into the carbs air/fuel streams. Stories to these systems seem to abound.

Evidently with rules changes bottle injection for what ever purpose went out of use for SnowMo some years ago.

[John (Taylor) Gabrowski]

MSD amongst others makes and sells water injection kits for 2 stroke performance exhausts uses in marine 2 stroke applications. The kit pictured in this thread is not an MSD system but resembles the component relationships anyway, so it must be some one else's kit for sale to the public for 2 stroke use.

Their (MSD's) (circa 2007) article can be summarized as follows:

Water Injection Control Systems

Injecting water into an exhaust system fools the engine into thinking it has the best of both worlds.

Exhaust systems cause racers to compromise their engine’s power. Exhaust systems are designed to be tuned to deliver maximum power within a specific rpm range. Performance can be gained by using the exhaust pulse waves to create pressure variations which have an effect on the rate as the exhaust gases exit the combustion chamber. The problem is that you are limited to that one power band which compromises your power!

Fortunately, *** offers the Pulse Width Modulated Water Injection Control Kit that allows you to modify the exhaust at programmable rpm points by injecting water into the pipe. Introducing water to the exhaust alters the exhaust pulses thereby modifying the back pressure! With this technology you can “tune” your exhaust system throughout the rpm range of your engine.

For example, by injecting water into the exhaust chamber at lower rpm, the density of the exhaust pulse is increased which slows it down. This has the same affect as lengthening the chamber to increase low to mid range torque and power!

The ******** Kit takes the engine rpm signal and processes it through a digital controller which pulses a solenoid to allow water to enter the exhaust chamber. The system can be installed on virtually any watercraft and features dip switches for easy adjustment of the rpm activation points. There are also bright LEDs that alert you as to when a solenoid is pulsing water into the system and to confirm a solid trigger signal from the ignition.

It seems the 2 stroke water injection kit I purchased and pictured in Harrison Racing Outboard thread is something older and less developed than what is around today made and distributed by "Snow" or "MSD" and others that are now very programmable and digitally controlled too boot! One thing is for sure when you see their (MSD's) price lists is water injection for what ever the purpose is not inexpensive by any stretch either.