couple engine questions please.

hi everyone, first time builder here so bare with me. Ive been rebuilding this 1981 kz440 for a couple weeks now and ive come across a couple issues.

1. one of the carbs seems to be leaking from the drains. its just a drip or two every few seconds. im assuming the only way to fix that is to clean the carbs? i read around that it may be a bit of rust clogging or making a float stick. it started as a straight surge of gasoline and as i fiddled with the bike it slowed down to barely anything. from what ive read, the drains should be dry the entire time is that right?

2. the engine runs GREAT, however it just started only wanting to start when im sitting on the bike, maybe a ground issue?

3. occasionally after i start and rev it, it will stay at the revved rpms at idle. im assuming this is due to the flooding of the carbs.

as to the flooding of the carbs, i left the tank on prime an i flooded them myself to begin with. is it possible that i just filled the bowls super high on accident and just need to empty them somehow?

any advice for this newbie is much appreciated.

Hi, I haven't worked on a 440 for years, but I'll offer up this in the hopes it may help you...
1. First - just a safety warning - play safe with fuel leaks - don't take a chance when anything more than an occasional drop is coming out of the carbs - don't run the engine like that. Keep a fire extinguisher handy when working on carbs with a running engine. If possible, have a buddy at the ready to use the extinguisher while you are working if a fire breaks out. If your carbs are dripping, place a small absorbent rag under the float bowl to catch and soak up the fuel. Don't let fuel get anywhere near the exhaust system. Don't run a bike like that in your garage or near buildings - outside only and away from anything that could also catch fire. Be ready to shut the engine off quickly at the slightest hint of trouble. Gasoline fires can get ugly very fast. Go ahead - ask me how I know these things!

Now, in my experience, often older carb float needles that have hardened with age will leak after the carbs have been sitting dry for a while. The leak starts out big like you say, then diminishes after the fuel has soaked the needle a few times. Most often it gradually stops leaking completely on it's own.

With the engine stone cold, try and drain the carb bowls a few times to flush out any accumulated dirt and debris. Drain into a small container so you can see that what is coming out is clean fuel. If crap keeps coming out with the fuel, you will need to remove the float bowls and thoroughly clean them out. It would be wise at that time to replace the float needles and seats with new ones form Z1 Enterprises as per the service manual. If the engine runs fine otherwise, you shouldn't do anything more with the carbs.

2. This sounds like your battery and /or starter circuit connections might be loose. Does the engine refuse to turn over with the electric starter motor unless you are sitting on the seat? If so, it is very likely there is a wire / battery cable loose somewhere. First carefully disconnect the battery ground cable to prevent shorting out the battery while you are working on the wiring connections. Check all the connections from the battery to the starter motor for corrosion and carefully clean and tighten them. Lastly, re-connect the negative battery cable to the battery and try starting the engine.

3. This sounds like a fuel / carb problem also. Specifically, something called an intake vacuum leak. But it could also be caused by your fuel leak / flooded carbs. Don't try to fix this until the fuel leak is resolved first. Then if the problem is still there, check the connections between the engine and carbs for being loose, cracked (the rubber manifolds often crack with age), or missing the little vacuum plugs that go over the small tubes that are used to connect vacuum gauges (during engine tune ups) to the rubber intake manifolds between the engine and carbs. One less likely but much simpler possibility, make sure your throttle cable(s) and linkage are free to snap back to idle easily and not binding / sticking....the throttle should literally snap back when you let go of the twist grip...

Time to go through the carbs. Pull them off and take them apart. All the way apart, and soak the hard parts in Berrymans carb dip or similar. Replace all the various O-rings but leave the original jets. Do NOT purchase crappy aftermarket carb kits since they are full of inferior brass jets and such. Places like Z1 Enterprises should sell the various O-rings and gaskets you may need.

While you are at it pull off the rubber carb boots and replace them. The hanging idle you are experiencing is due to an air leak. Best to get new boots for the carbs in front and the airbox too if they are hard and won't seal to the carbs right.

And be sure to adjust the valves.

Do this work right and you will fix the bike the first time. Shortcut the cleaning process and most likely you will become an expert on how to pull off the carbs because you will be doing it again and again.

A few further thoughts on the situation...

1. Check that the fuel tank is clean inside...particularly check for rust. If the tank is rusty, that is a whole other matter and best left to a professional for repair.
2. The problem with your idle not coming down from high revs could also be caused by engine intake / exhaust valves being out of adjustment, but I find that highly unlikely from your description of the symptoms and condition of the bike.
3. If you are a complete newbie with the tools / engines, and carbs specifically - my recommendation is to find a mechanic trained and experienced in carburetor rebuilding (preferably a professional) willing to assist and mentor you before diving in and taking your carbs apart for a complete overhaul. It doesn't have to be a motorcycle technician. Most small engine (i.e. lawnmowers, chain saws, etc.) technicians are familiar with general carb maintenance and repair and can guide you through the process and recommend proper tools, cleaners, and methods. Bribe one (cash works best, followed by beer and women) if you need to! Or sign up for a small engine repair training course at a community college if you can spare the money and time.
4. Yes, as per Nessism's comments - buy only quality carb and engine parts from Kawasaki (genuine Kawasaki parts whenever available) or a respected specialist supplier like Z1 Enterprises. you'll save more than just money in the long run. Buy carburetor parts like jets, floats, needles, gaskets, o-rings and valves manufactured by the carb manufacturer (Mikuni, Keihin, Hitachi, etc.) whenever possible, or from Z1.
5. Because you are a beginner, I suggest adherence to that old saying - if it ain't broke - don't fix it. You don't need to go looking for trouble - trouble will be looking for you. Fix the fuel leak, then the starter problem, before looking at the idle speed issue. Having said that, you might save some time and effort if you purchase all the carb parts needed for a rebuild before you start. Call Z1 and ask for their help on ordering the necessary carb parts...

Good luck!

Another supplier I use. Good for research too.
Steve
jetsrus.com/