ZN1300 Voyager Fuel Injector Service

		ZN1300 Fuel Injector Service

Last Update 8/22/08

This is what I use when I have my tank off the bike to work on it but need to hook the fuel lines back up so I can start the motor. It's just a dolly with a 4x4 of the right length and a piece of 2x4 screwed to the top.

I took a small piece of metal pipe and screwed it on to hold the front

And in the back I use a lag screw so I don't have to worry about it coming off if I move the dolly. With it sitting on the dolly in the direction I show, the weight balance makes it very stable.

This is how I spliced a fuel pressure gauge into the return line and in front of the regulator. I later found out that there's a better way and I'll be installing fuel pressure regulators with gauges in the future. You can get a fuel pressure gauge off ebay for as little as $17 even with liquid filled gauges, but the last thing you'd want is to install a cheap gauge and have it spring a fuel leak while you're riding. Can you imagine what kind of fireball that would make!

I bought a B&M gauge locally for $35 that was not liquid filled and it works OK, but the needle does bounce around some. The better idea is to buy an adjustable fuel pressure regulator as they have gauges on them too and we can replace our stock regulator with an adjustable one and it will have a gauge built in. The benefit of this is twofold. The stock regulator was $125 from Kawasaki last time I bought one and they do go bad on occasion. A lot of people still have the original and they're pretty old now so we can buy an aftermarket one to replace it with and get a gauge too. I've seen adjustable fuel pressure regulators on ebay as cheap as $23 with a liquid filled gauge! A good quality one might run $100 or more, it's your choice.

The gauge is nice if you suspect a fuel delivery problem and think maybe your pump is going bad as you can glance over and monitor your pressure when you're working on it. The second benefit is being able to adjust the pressure itself. I was talking to Mike Chestnut with Horsepower Unlimited who's a Kawasaki ZX750 Turbo specialist. Here's what he has to say about these:

"The problem with the bike is that it was lean from the factory to meet US emissions when new. Pump gas in this country has changed dramatically in the last 20 years. Today's fuels are highly oxygenated, and burn 10 - 15 % leaner than they did now, which makes the bike incredibly lean. You compensate for this by turning up the fuel pressure. The regulator that I sell is an exact replacement for the factory one. The bike will actually run better than it did when it was brand new. All of the early Kawasaki fuel injected bikes suffer from the same problem. Plus you can also use the regulator to tune the bike for mod's, such as exhaust pipe, piston kit, and so on. I have sold 100's of them over the years. The price is $95.00 exchange. I need your stock regulator as a core. I am so sure that it will make your bike run much better, that I will give you a money back guarantee."

So next time I take my bike apart I'm going to start using one of these and see how it works. Of course you can only turn your pressure up as high as the pump is actually capable of putting out, but they do have probably an extra 10 lbs or more of pressure capability engineered in. I'll experiment with this an post back what I find.

If you pull this vacuum sensor off and lay it to the side you can get to the hose that runs between the airbox and emission control air injection valve.

You can slip these injectors off as a unit with the distribution pipe and the holders as shown here after you get the top airbox off. The hoses are crimped to the injectors on some types of new injectors, so try not to damage the hoses. Easiest way to disassemble is to pull the 9 screws that hold all the injectors to the throttle body and the whole set of 6 injectors with the fuel rail will come right off no problem as you see in the picture.

Then you just work the 3 plastic pieces off that each hold 2 injectors together. Then you pull the rubber seals off. A small one on the bottom of each injector, and a big one on the center. You may need a super small screwdriver to get up under it and work it over the lip on the injector body and slide it down and off. Be careful and don't damage these though they're easily replaced if you do.

Now slip the metal (OO) double rings off each pair of injectors. To remove each individual injector from the fuel rail you loosen the clamps and slide them down towards the injector as far as possible. Twist and pull each injector off the fuel rail one at a time. If they seem to be stuck to the rail, it helps to use some silicone spray. A spray you can get from any auto parts store that's made specifically to spray on rubber when attaching or detaching rubber hoses.

Use that small screwdriver if it's small enough, or I actually use the pointed tip of a 12 volt test light because it's pretty long, it has a strong tip, and it has a handle. Slide it in between the hose and the fuel rail slightly and spray the silicone in and work it around best you can without damaging the hose in the process.

Since yours hasn't gotten hot yet from being used on the bike, they will probably come right off and you won't have to go through all this. Be careful with the ends of the injectors because they can be damaged.

Once you're in to this injection you should make sure all your hoses are in excellent shape. I offer injectors on an exchange basis on my parts page that are ultrasonic cleaned and flowed and they come with new seals as shown here. Old seals in the top of the image, new ones at the bottom.

Here's how I solve the air filter problem to make it always fit tight. I think that's 3/4" heater hose I used, but I cut a piece that's about 75% of the length of the filter and jam it up under the filter and then put the cover on. In theory the cover is supposed to hold the filter on one end and the other end sits on a tang at the far end. When I had my throttle bodies off one day I bolted the top airbox piece back on and installed the filter. What I found was that it didn't fit very tight and on the K&N filters they can actually bow in the middle as the filter is only being touched on the outside ends by design. This hose puts constant pressure all the way across and there's no air leaks with dirty air getting into your motor!

NOTE: On these newer browsers I've noticed that they don't always display my large images in full size when you open an image from the thumbnails. Once you click the thumbnail and open the larger image, if you 'mouse over' the image you should see a " + " symbol or some other indicator like a box with arrows usually on the bottom right edge of the image. If you click on the indicator, then the image will expand to it's full size which displays full screen on computers that use a 800 x 600 resolution setting for the monitor. If you click the indicator again it will go back to the smaller image. Some people use a resolution setting of 1024 x 768 or higher on their monitors and for those users the images will appear smaller than full screen in size. You can change your monitor settings easily enough if you desire. Also, the indicator I've noticed is slow to appear even after the image appears to of completely loaded. The indicator in Netscape seems to be a lot faster to display than the one in Internet Explorer.

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