accelerator pump doesn't pump.

[wyly]

Z

[spencer]

wyly, if you're sure the pump check valves and the diaphragm are ok, the next most likely thing is the six accelerator pump nozzles in the carburetors. If the carbs are off the bike, it should be easy to test them by spraying some carb cleaner in the passage which leads to the six nozzles. See Mike Nixon's book for how to do it. (I assume you have Mike's book.) If all six nozzles squirt, there is not much left to do. If the carbs are still on the bike, it will be harder to test the nozzles for blockage.

While sending your carbs to Dave would be a foolproof way to know they are right, there is nothing wrong with doing it yourself. When you said you cleaned the carbs ultrasonically, I assume you disassembled them first, and did not just dunk the whole rack of carbs in an ultrasonic cleaner.

[wyly]

Z

[spencer]

I know that many people who are mechanics resent being told anything by a customer. I also know that many people who have experience cleaning carburetors fail when they think they can treat CBX carburetors like any other carburetor. I'm not sure what to tell you to do now. A non-functioning accelerator pump will not stop your CBX from starting and running, but if it really does not work, after someone just cleaned the carbs, that probably is an indication of how good a job was done on the rest of the carburetors. Best bet is probably to send them to a real expert such as Dave or Mike or another of the experts who hang out here, but if your budget does not allow that, you can probably do it yourself if you pay attention to detail and follow Mike's book religiosly, and take it slow. Properly cleaning a set of CBX carburetors takes considerable time, even for an expert.

[whatscooking]

Your nozzles are plugged. I cleaned and cleaned the two sets of carbs I did and when I tested each one most were plugged. Somewhere along my journey with these carbs someone had a write up using the rubber plugs that are used to plug the idle jet tower. Taking two and a pair of pliers and squeezing them together to open that passage up, it works but compressed air did it for me also. Learn to use your spray cleaner to check.
Also on both of mine I had to make sure there was just the slightest bit of clearance between the pump plunger rod tip and the little arm that rest on it. Then I had to use washers on the spring to help it out. Mine would squirt fuel out several inches.

[wyly]

z

[wyly]

Z

[Mello]

Hey wyly, most of us are amateurs when compared to Dave, Mike et al. The stripping and cleaning of these carbs does seem daunting but if you work slow and steady following Mike's excellent instruction, a reasonable result can be achieved. I was lucky that my first set of carbs were not too bad and that the pump circuit was relatively clear. Only 2 nozzles did not squirt fuel. I have a set of carbs that I must still get to and these are really bad with no fuel getting through at all.

Give it a go!

[wyly]

Z

[Sharpie66]

Being a complete amateur here, I can state with confidence that with Mike Nixon's book in hand and the gracious sharing of years of CBX knowledge here on this forum, you can most certainly disassemble your carbs and successfully service them yourself. I did two carbs this past winter. One had been stored for 27 years and was clogged everywhere. The other not so bad. Both had the check valve in the accelerator pump cover gummed up. Carb cleaner and air took care of the blockages.

At the risk of pointing out the obvious, is it possible the cotter pin or the plastic sleeve that holds the spring in place has not been installed properly.....

image.jpg

I'm great with details but often overlook the obvious. By the way, Randaak ships his carb kit out very quickly. My first set took 2 weeks to complete and the second set I was able to do over a weekend. There is still hope you can get out riding before the season ends. The best tool you will ever have is this forum!

Wish you luck in whatever you decide to do.

Patrick

[herdygerdy]

A couple of suggestions......

1. On two occassions I found I had forgotten to install the special O ring on carb. no. 3, which sits on the top of the float bowl and is in addition to the float bowl gasket. This O ring seals the accelerator pump input circuit completely and if not fitted, fuel may escape out the side of the junction between float bowl and carb body if missing. Herein lies the important lesson of bench testing your carbs before they get anywhere near the engine.

2. Here is the tip on clearing the blocked accel. pump jets I came up with. On one set I had ultrasonically cleaned, I found three jets that were previously perfect came back blocked - probably not blown out by the ultrasonic operator once they came out of the tub. This trick in pics below changed that situation from an OMG moment to a far happier one. But it only works if the carb bodies are split. Just lay the body on its side with one of the two plugs installed on the bottom. Then carefully fill the top hole with carb cleaner, all the way to the top. May need to tap the carb body on the bench a couple of times to get any air out. Then put the second rubber plug on the top of the fluid. Firmly squeeze the two plugs together with some big ass multi-grips and let the wonders of hydraulic pressure and leverage work their magic!





3. And this use of two small square match ends when putting neighbouring carbs back together will save you much cussin' and tears......



Keep at it Wyly, keep us posted on progress, we are here to help.

Cheers...Tony