Carb Slide Problem

[Donvito]

Thanks to all for your help in my last post especially Gary who walked me through the carb cleaning process. I am happy to say the bike is running better but there is still a problem. The left rear carb, #1, slide doesn't move when observing it through the intake. The other 3 do. It also will spit gas out sometimes when I hit the throttle.

 

I removed the diaphragm and slide and they are moving freely and the diaphragm looks good. The vacuum port plug is on and I don't see any obvious leaks. What should I do next. Thanks.

[Peder_y2k]

That gas spitting is indicative of either an improper fluid level in the carb (float level), or a loose/leaking main jet/emulsifier tube.

Others will chime in here on this issue.........

-Pete, in Tacoma WA USA

'83,88VR

Edited May 25, 2013 by Peder_y2k

[Snaggletooth]

One detail to ask about. Did you get the small o-ring at the bottom of the diaphragm cover back in place when you put the covers back on?

[mbrood]

Pete has the floor on the spitting, I believe. For the "reluctant" slide, did you insure the integrity of the SMALL o-ring just inside the carb diaphragm cover?

[usedcyclesales]

Thanks to all for your help in my last post especially Gary who walked me through the carb cleaning process. I am happy to say the bike is running better but there is still a problem. The left rear carb, #1, slide doesn't move when observing it through the intake. The other 3 do. It also will spit gas out sometimes when I hit the throttle.

 

I removed the diaphragm and slide and they are moving freely and the diaphragm looks good. The vacuum port plug is on and I don't see any obvious leaks. What should I do next. Thanks.

 

Glad I could help:) One other thing I do once cleaned is use MARVEL MYSTERY OIL, not every tank full but maybe every other or so. depends on how often you drive. It's more of an all around lube,cleaner, stabilizer type additive. I'll leave you to these other guys on the slide issue they're the expertise on that is far superior than mine . And feel free to call ANY TIME for help.

[abusive throttle cranker]

There is a black tube from each carb which goes thru the loop and sticks out the side under the carburetor assembly. It plugs onto a little black plastic nipple. I replaced these tubes with clear tubing much like aquarium tubing. Brace these tubes so that they are near vertical and the end is above the center of the slide. Then open the drain screw and turn on the key. Turn the key off and on several times till the fuel pump doesn't click any more. Then look at the fuel level in the tubes. The fuel level is equal to what it is inside the bowl. Adjust as needed. It should be 15- 16.5 mm below the center of the slide. Of course all 4 should be equal.

 

P.S. the bike should be on the center stand and the front elevated a bit to make the carbs as near vertical as u can when this test is performed.

[KIC]

There is a black tube from each carb which goes thru the loop and sticks out the side under the carburetor assembly. It plugs onto a little black plastic nipple. I replaced these tubes with clear tubing much like aquarium tubing. Brace these tubes so that they are near vertical and the end is above the center of the slide. Then open the drain screw and turn on the key. Turn the key off and on several times till the fuel pump doesn't click any more. Then look at the fuel level in the tubes. The fuel level is equal to what it is inside the bowl. Adjust as needed. It should be 15- 16.5 mm below the center of the slide. Of course all 4 should be equal.

 

P.S. the bike should be on the center stand and the front elevated a bit to make the carbs as near vertical as u can when this test is performed.

 

 

Great idea !!

[pmelah]

seafoam lots of seafoam ..................... ok yammer Dan its been said

[Donvito]

Thanks. I switched the slide diaphragm assembly with the right rear carb and the problem moved also. So, it is a problem with that assembly. There is a small hole in the diaphragm so I guess I should repair that. I know there is a lot of info on repairing diaphragms and I've done it before but I can't remember what I used. Any help there?

 

Also, what should I be looking at on the slide and needle valve? Someone mentioned "loose/leaking main jet/emulsifier tube" but I don't know what that is or how to check it. Thanks again.

[Peder_y2k]

At this point, concentrate on the slide/diaphragm assembly first. the slide should move with just a little resistance from finger pressure, but zero sticking. If it sticks, closely examine the slide for burrs. The diaphragm should have no rips, but a few pinholes are OK for now. The rim that seals the diaphragm to the carb body needs to be uniform all way round, so look for anything unusual that seems irregular.

Since the problem moved with switching the slide to another carb, the main jet/emulsifier tube is not the primary issue. There's something about the slide/diaphragm/needle that's not right.

Tool Dip is a good product for filling the pinholes in the diaphragm, the kind used for coating plier handles. Just a drop on each hole will do.

-Pete, in Tacoma WA USA

'83,88VR

[Snaggletooth]

If you are finding enough pinholes to be a concern here is a fix that holds up extremely well.

 

http://www.venturerider.org/forum/showthread.php?t=71496

 

Or a dab of the liquid version would patch a larger hole for a temp fix.

 

But if you are dealing with a hole large enough that you're not getting any movement on the slide you are needing to look at replacing that diaphragm.

 

But inspection of the slide for free floating movement would be the first step. Cracks, worn spots, a loose diaphragm or a ridge would prevent the slider from working properly.

[Donvito]

The slide move freely. I have a question about the needle valve. I am including pictures. there is a gap between the lock washer (not sure of the correct name) and the spacer. I never removed this so I assume it is correct. There is a small tab on the spacer which I know goes into the corresponding hole in the slide. Then there is a spring and a washer. I assume the spring goes against the spacer and the washer above the spring and before the screw but I'm not sure of this. Please let me know the correct set up. Thanks.

 

[ATTACH]76899[/ATTACH]

 

[ATTACH]76900[/ATTACH]

 

[ATTACH]76901[/ATTACH]

[Snaggletooth]

You might find some useful info here.

 

http://www.venturerider.org/forum/showthread.php?t=28432

[abusive throttle cranker]

That diaphragm looks useable. In my case the small washer was on top of the circlip. I was running hot and lean so I put it under the clip thus lifting the needle. I'm not sure of the original setup. The PO had taken the carbs off and played with them. They were off the bike when I got it.