Clay, you have a tiger by the tail. There are a lot of little parts to the carb system. I will try to assist you in the basics without carb removal. This may require a few replies back and forth. Start by turning off the gas then drain the carbs. Now turn on the gas and check to see that fuel flows into each carb. If gas starts flowing out of all the float bowls, now that the gas is back on, then all carbs are getting gas. To drain the carbs just remove the drain screw on the bottom of each carb float bowl. Two carbs have the drain screw on the left, two have it on the right side. Reply with what you find.
Testimonial: "Tombones45 is helping me with a problem out of my knoledge. He is awsume and responds. Thanks again. We'll get it fixed."
Tombones- thanks. tank is off to get to the carbs. how would I get fuel to them now? Reinstall tank and turn on fuel and watch screw holes for fuel? I see the drain flat head screws at the bottom of each carb. they are not adjustable at all, right? I cant screw their adjustment up at all right? can I spray carb cleaner into the fuel lines that enter the carbs? with drain screws in or out?
when I loosened the drain screws fuel came out of each carbs, without the tank on, just residual fuel.
Yes, mount the tank but it doesn't need to be fastened down. Just slap it into approximate position. You can't screw them up unless you mess up the threads when reinstalling. They have no adjustments. They are just plugs. One step at a time. Carb cleaner comes later.
with drain screws loose, can I spray carb cleaner in the fuel rails?
tank now back off, air box is off, and carbs are getting fuel. Screws are back in.
Good enough with out the tank. Drain about 1/2 cup out of the tank anyway. I want to be sure any water in the tank is gone. Carb cleaner is okay. Put the screws back in place. Now check for spark in each plug. Remove all the plugs then , one at a time, hook up the coil wire then ground the side of the plug against the cylinder head. Crank the engine and be sure each plug sparks using it's own coil wire. It is best to have a fire extinguisher handy in case things get messy. So, do each of the coil wires provide a spark? Gotta go now. Talk to you in the morning.
What do you mean carb cleaner is ok? Can I spray in the fuel rails and in the air intake aluminum stacks? Anywhere else? Should drain screws be open or closed when spraying cleaner? Thanks, talk in morning.
Carb cleaner can be used on any part of the carbs. leave the screws open. Be aware that over spray onto paint and plastic can mess up the finish. HAVE A FIRE EXTINGUISHER ON HAND! ONE BACKFIRE AND THE BIKE IS TOASTED WITHOUT ONE. Here is the plan; 1) Drain the carbs to get rid of any water in the float bowls 2) find out if each carb is getting gas 3) drain some gas out of the tank to rid the tank of any water 4) check that each cylinder is getting spark from it's coil wire 5) check the carb diaphragms for proper operation 6) try either and intake blockage 7) remove float bowls and clean jets and circuits as best possible without removing the carbs 8) check diaphragms again 9) remove carb caps and check diaphragms for pin holes or tears 10) replace any diaphragms known to be damaged 11) take the bike to a dealer for service.
.
Below is an explanation of how your carbs work. It may help you understand CV carbs a bit.
The first part is the basis for all carbs. Your carbs are CV carbs. " CV " stands for Constant Velocity. That will come after the basics. I have to send it in segments because if my reply is too long, FixYa strips the info out of the file. THE VENTURI EFFECT
When air is still or moving slowly, it is dense and at a standard atmospheric pressure. But when air is forced to speed up faster than the surrounding air, it becomes thinner and less dense. This is known as a Low Pressure Area. And where a low pressure area exists, air at higher atmospheric pressure wants to rush in to equalize the pressure. This phenomenon of low pressure versus ambient atmospheric air pressure is basic to the functioning of carburetors.
How do we get air to move through a carburetor? When the piston goes down, it drastically increases the volume inside the cylinder and creates a vacuum. Open the intake valve, and new air will rush in to fill this vacuum. Throw a carburetor in that path and the descending piston now "sucks" air through the carb. And that's how we get an air flow through the carb. The vacuum, (created by the downward travel of the piston), is actually a low pressure area inside the cylinder, but we will call it a "vacuum" to differentiate it from the low pressure area we will be discussing which occurs inside the carb.
If the air path in the carburetor bore were the same size all the way through, outside air could rush through the bore quite easily to fill the vacuum being created by the downward travel of the piston. It would therefore take high piston speeds (lots of pumping) to achieve enough air speed through the carb bore to thin the air enough to create a low pressure condition inside the carb. However, if an obstruction, (such as a carburetor slide), is placed in the carb bore the air path is now much smaller. The air stream has to speed up greatly to get through this bottleneck. In this way, the air can be speeded up and a low pressure area can be created inside the carburetor bore.
In carb lingo, this bottle neck is called a "Venturi". As the incoming air speeds up to get past the Venturi, it thins out and loses density. We now achieve a "venturi effect" which is a high speed air flow creating low air pressure at the point of the restriction.
How is the venturi effect used in the carb? We know that, at the point of the low air pressure, outside air would love to rush in and equalize the pressure. For example we could drill a hole to the outside air at the point of the venturi and outside air would rush in. But the clever carb guys instead drill a hole which goes down into a bowl of fuel with outside air above it. The higher pressure outside air can't get up through the hole, (it is blocked by the fuel in the bowl), but it does try, such that it pushes down on the fuel in the bowl, thus forcing some of that fuel up a pipe and into the depressed air stream flying by the venturi. The low pressure created by the venturi assists in drawing in even more fuel. That plume of fuel coming out of the pipe mixes with the air rushing by, and that is how we get an air/ fuel mixture to feed the cylinders.
Get back to me after reading the info on carbs.
thanks for the info. I believe I am going to take coils to Honda to test them. do i need to take the plug wires also, or just the coils?
Take it all.
thanks I will take it all. Air breather, tank, ect, is still off the bike will it goop up carbs or hurt anything, if I leave the carbs empty for a day while I wait for Honda tomorrow? Im thinking that one coil is weak? I covered upper engine with towel and placed paper towels in the 4 aluminum air stacks.
also, if one coil is weak, do we usually replace both or just the weak one? Thanks for all your help!
Your bike only has two coils. Each coil does two cylinders. Just replace the bad coil if one is found to be bad. Reply with your email address and I can send you a PDF of the rest of the CV carb info. I can also send diagrams that way. The "comments" and "Replys"on FixYa do not support posting diagram files, photos or large batches of information. The carbs can be in the open without harm.
Tombones49- here's my email= [email protected] (one "r" at the end of Norbery). Thanks- you're freaking awsume! The bike would possibly still run fairly smooth if one coil was weak? note plugs look the same when removed.
It could run seemingly smooth. I am emailing a diagram of the coil layout. and the rest of the CV carb info.
×
1,401 views
Usually answered in minutes!
×