Hydro-Extra LLC

Improve your Engine Performance with Our Complete HHO Generator Kits

                        Installation and operating Instructions

First locate a cool place within the engine compartment to place your generator; we find that in front of the radiator is a great place, if your vehicle allows for you to attach in this area.

For Vehicles with OBDII computers 1996 and later, you will need an O2 sensor extender or EFIE Enhancer or MAF/MAP enhancer. If you use the extender provided with your kit you will need an O2 sensor socket. You can purchase these from just about any auto supply store.

Disconnect the O2 sensor wiring plug making sure you take notice of it’s routing, so that you can route it back the same way it was. You need to disconnect the wiring plug because the wire needs to rotate with the O2 sensor while removing. Use an ample amount of never seize on the O2 sensors threads and extender threads being careful not to get any never seize on the O2 sensors probe as this could harm the O2 sensor.

Screw the extender in first and tighten snugly, do not over tighten. Then screw the O2 sensor into the extender, tighten snugly also being careful to not over tighten as you do not want to break this off in your exhaust. Re-connect your wiring plug. You will need to do this with only your pre catalytic O2 sensor(s) as some vehicles have more than one. Do not install unless you plan on running the generator continuously, as these could cause your engine to run to lean.

Next find a 12-volt power source that is only hot when the key is in the second position or when vehicle is running. This can be achieved with an ammeter. You should not have any power to this wire when the key is off because you do not want your generator powered when the vehicle is off. When your vehicle is running you should be reading approx. 14 volts, as this is what your alternator is producing.

 I also recommend that you use a 40 amp. relay and a 30 amp. auto reset breaker, these are supplied with all of our plate design kits.

On the carriage bolt design either bolt can be positive. On the plate style you will notice that the top of the positive terminal is red for positive, so you do not have to guess which terminal to hook to. Your pre-assembled ground wire can go directly to your negative battery terminal. You will need to mount your 40 amp. relay close to the battery. Run your 30 amp. auto-reset breaker from the battery to your relay. The 40 amp. relay that is supplied with your kit gets hooked up accordingly. #86 terminal from switch which is activated by your ignition. Usually you can find a hot wire at the distributor when your key is in the second position or when vehicle is running, this wire must shut off with your keyed ignition switch. #87 from battery to 30 amp. auto reset breaker then #87 from your 30 amp. auto reset breaker to relay. #85 to battery ground. #30 to generator. Your amp meter can be wired inline between the generator and your ground which is the negative line. Neg. into the 35 amp. toggle switch then to the amp. meter and negative out of your amp. meter to the negative terminal of the battery.  

Next locate your intake plenum to your carburetor or injector manifold after your air filter and after your mass air flow sensor if equipped with one. I find that the closer you can get to the throttle body the better, but all vehicles are slightly different.

Disconnect the intake plenum boot completely off of the vehicle so the particles from drilling can be easily cleaned. After drilling clean the surface well prior to inserting the nutted elbow.

Drill a 5/8” hole in your boot for the 3/8” barbed nutted elbow that is provided with your kit, use some RTV high temperature sealant around the threads on the inside of your boot prior to screwing the nut on, then tighten the nut snugly careful not to over tighten, then apply some more RTV high temperature sealant around the outside of the nut and threads to prevent any leaks. Re-install the boot.

Now you are ready to hook up the 3/8” supply hose provided with your generator kit.

All of our generators come with a check valve attached to the intake plenum nutted elbow, only letting HHO flow into the throttle body. The flashback arrestor attaches to the hose coming out of your bubbler and as close as you can get to your air intake plenum connection.The bubbler gets hooked up to the bubbler hose barb with no tube that is submerged within. The bubbler hose barb with the tube that is submerged is the inlet from the generator. Run your hose from your generator to this connection.

We use a small amount of Vaseline on the generator rim and threads, which helps to ensure a seal for the lids and allows for easier opening.

Now you can hook up your intake plenum hose and run your engine until it comes up to full operating temperature. A good rule of thumb, if your commute is an hour one way you should run your vehicle for 1 hour and watch for increased amperage over this time period to see how high your amperage has risen to. Typically your generator will never go any higher after an hour of run time.

Feel the generator for heat to make sure it is not running to hot, do not run higher than 140 degrees Fahrenheit . If it is to hot dilute your electrolyte (distilled water and potassium hydroxide.




You will have to tighten the two nutted elbows once you determine which direction they will need to face.

 Start with an 1/4 tsp. of potassium hydroxide and distilled water keeping the level 1½” from the underside of the lid to prevent sloshing/overflowing. Mix well, then screw your electrode lid assembly together. The bubbler only uses distilled water, approximately 2/3 full. Double check your hoses and wires to ensure that they are safe from hot and moving components, use wire ties as necessary.

Make sure your generator is secure so that it does not jump out of its bracket or knocks against hard surfaces.

Start your engine and check for production, start at 6 to 8 amps cold, a good rule of thumb for adding electrolyte potassium hydroxide is if your commute is one hour run the generator for one hour and see how high the amperage gets. Although this isn't real accurate as your generator will run cooler with air from traveling, but it is a good starting point.

The electrolyte sodium hydroxide is the only thing that will increase or decrease amperage. Your amperage can go up by 10 or more amps once your generator is fully warmed up. If your amps get above 15 amps. I would dilute the sodium hydroxide. Just dump some of the water off, and add plain distilled water repeat until desired amperage is achieved. 

The 316L S.S. plate design, which is our best producer, only requires 1/8 to 1/4 teaspoon of sodium hydroxide. You will need to add additional electrolyte if you are running in series (multiple generators) to increase production as you will be running at lower amperage. 

 The object is to maintain a running temperature of no more than 120 degrees farenheit or 60 Celsius or just below. I find that no more than 8 - 12 amps are sufficient, you can purchase an indoor outdoor thermometer at most automotive stores for less than $15.00, put it on your dash and run the sensor to the generator and use electrical tape to tape the sensor to the jar towards the top of the lowest water level, or just below the top of the plates, this will allow you to monitor the generator temperature. 

The 3/8” hoses with the barbed fitting seal very well, but if you want to, you can put hose clamps on all of your connections.

The miles between cleanings is dependent upon how clean your generator stays and your amperage, if the generator is staying relatively clean and the amperage is being maintained, you will only need to add distilled water. Cleanings consist of dumping out old electrolyte and distilled water. Then add distilled water and potassium hydroxide. You should check your water level between fueling at minimum. It is better to monitor your distilled water usage until you get a better feel for how much you are using. If it appears to be getting low just add more distilled water. The electrolyte, potassium hydroxide and distilled water, only needs to be added when cleaning. I have seen approximately 3500 to 5000 miles before the generator(s) need recharging.

In cold weather where you have freezing conditions increase potassium hydroxide level as your amps will be lower in the winter. This will make the water more conductive and prevent the generator from freezing at colder temperatures. The bubbler can be filled half with distilled water and half with devil springs vodka to prevent from freezing. Devil springs vodka is 160 proof and will not freeze.









Hydrogen Gas is Extremely Explosive and Extreme care should be taken when testing and adjusting electrolyte proportions to increase amperage.

Before installation, although it is only a medium complexity system to install, we highly recommend that you consult with your mechanic first.