accelerator pumps missing

I have some really important questions that I hope are easy to answer and informative to anyone who reads this.


First of all, long story really shortened, my bike used to run fine and doesn't anymore. In the process of taking apart the carbs however, I noticed that the accelerator pump that was/is supposed to be part of the 1979 KZ650 carb setup, is not there. So basically, my carbs are just open ended where that pump could hook up. So, the question is: Is this ok? Can the bike run allright without the accelerator pump in place? I mean, it must have before . . . they have to have been missing since I bought the bike in 2004.


Next, I bought new jets and gaskets for the carbs. Are the old jets ok and clean enough if they LOOK clean enough? I mean, if the jet is clean and the hole is not obstructed, it should be fine right?



Putting on new gaskets. Is there a technique or an application glue? Or do I just stick them right in there as is and tighten the bolts.



Last but not least, IF (and I imagine I will) I still have trouble after replacing all jets and o-rings and a good cleaning . . . is it a possibility that the plunger system with the choke could give me trouble? How would I check that? The simple definition of what is not working on my bike is: It starts fine, it runs ok . . . as soon as I go and ride it though, she doesn't run good at all . . . 5 minutes after the engine is warm, it is as if she gets fuel starved when revving. I don't think it is fuel related, as long as the bowls are full it should be fine right?


Thanks for any help and insight.

Post edited by: b4schroer, at: 2007/05/09 19:45

I'm not too sure what you mean by the carbs are "open ended" where the pumps should be. The #2 carb is the only one that actually has a pump the other three are hooked to the pump somehow, my 78 didn't have a pump so I'm not sure how they are connedted.
Put the gaskets on dry with nothing on them. If you have new jets and they are the same size why not use them?
While you have them off the bike, disassemble them from the bracket if you haven't already and check the fuel tees between the carbs. They will get full of crud and cut down the fuel flow to the carbs. When you put it all together, install or replace the fuel filter with a new one.
Good Luck,
Ride safe.

Post edited by: The Milkman, at: 2007/05/09 20:24

Open-ended means that the 4 openings . . . of which #2 is supposed to have an accelerator pump on it and the other 3 are attached to that . . . all have nothing attached to them, they are just open holes.

Sorry, I can't help you much with the pump setup. Like I said mine didn't have them and the Clymer's manual doesn't explain or show them well at all. If you are saying that the pump isn't there either though it seems that there would be gas leaking out of it all the time. By the way you aren't talking about the overflow pipes that hang down from the bowls are you?? They are about in the center of the bowls and should have hoses hooked to them and draped over the rear of the engine in case a float sticks and over fills the carb.

Post edited by: The Milkman, at: 2007/05/09 21:22

del

no, I am talking about the accelerator pump for certain. I have the manual, and according to it, every '79 650 should have an accelerator pump on the carbs. I'm just hoping that someone here will verify that they are not necessary. In addition, there is no way that gas could be leaking out of them, the channels that the pump should be hooked up with lead directly into the chamber where the air and fuel mix, it should never be exposed to fuel being able to go backward down it. I believe, though I may be wrong, that the accelerator pump is a direct unit for additional air supply, it is independant of fuel.

JMKZHI wrote:

If the bike isn't leaking fuel all over the place, then the pump circuit orifices must have been plugged.

Just curious... Are the pump nozzles still there? They project into each carb bore on the airbox side. JMK.<br><br>Post edited by: JMKZHI, at: 2007/05/09 22:09

Well, with my limited knowledge, what is inside the chamber leading to the engine are two holes. One hole is from the fuel jet which gets plugged or unplugged by the needle. The other hole (much smaller) leads to where these accelerator pump hoses should be connected. I can't see daylight through it so maybe it is plugged?? If so, let's assume it is plugged, does that mean it should be fine, relative to this specific item(lack of accelerator pump)?

Sorry for my lack of proper terminology with all the parts.


In addition . . . there are no "nozzles," I don't see where there would be any in the manual either . .. unless I am missing something.

Post edited by: b4schroer, at: 2007/05/09 22:14

=

I do not have those nozzles


RE: the original post . . . can anyone comment on the chances of choke plungers ever having anything to do with carb problems.


Reason I ask this is simply that the choke plungers are the only part which was NOT included in my new carb kits that I just bought. So the plungers look ok, but the rubber on them is appropriate for carbs from the 70's.


Post edited by: b4schroer, at: 2007/05/09 22:39

Post edited by: b4schroer, at: 2007/05/09 22:42

sorry I missed that part of the question, yes if they don't close all the way or seal correctly you will be running too rich as if the choke is partly on. I have no idea where you will find them I don't use those carbs anymore so I haven't had to look for them. but Wiredgeorge has a write up some where here or in the archives about them.

can you post a picture of your carbs so we can see them?? It will help a lot.

I have a 79 Kz650 B3, I do not have an accelerator pump.. I do have however fuel and air mixture screws.[:blink: When the bike is running it runs great. You might not have an accelerator pump. Why would you think it jwould ust dissapear? Hmmmmmm?

b]b4schroer wrote:[/b]

no, I am talking about the accelerator pump for certain. I have the manual, and according to it, every '79 650 should have an accelerator pump on the carbs. I'm just hoping that someone here will verify that they are not necessary. In addition, there is no way that gas could be leaking out of them, the channels that the pump should be hooked up with lead directly into the chamber where the air and fuel mix, it should never be exposed to fuel being able to go backward down it. I believe, though I may be wrong, that the accelerator pump is a direct unit for additional air supply, it is independant of fuel.

The accelerator pump shoots a stream of fuel into the airstream through those brass nozzles you can see in the picture just inside the carb at the bottom of the throat. The fuel spray's function is to enrichen the mixture to help stop hesitation because fuel doesn't instantly come from the main jet and the lean condition causes a slight hesitation in the engine and if left lean too long it will backfire or stall or even both.

Post edited by: The Milkman, at: 2007/05/10 00:49

Also, in the picture, those nozzles that a hanging down on the very bottom of the carbs are the overflows that I mentioned earlier.

Post edited by: The Milkman, at: 2007/05/10 00:53