Carb issues

[Trader]

So here's the story relating to my 88.

 

When I first got it I needed 1/2 choke just to keep it running. MARCARL and I cleaned out every oriface possible with the carbs still on the bike with carb cleaner and compressed air. We set it up best he could and since then I have seafoamed it with a very strong mixture overnight a few times, and add several ounces every 3-4 tanks. Once in a while I put in a heavier dose .

It's had at least 8-10 cans thru it.

 

I had a case of a sticky float (I think)on the #3 carb earlier this year as gas was pouring out the overflow tube. But it "fixed" itself when I tapped on the carb body with the handle of a screwdriver (I was on the side of the road at the time). Again...dosed with seafoam and it seemed to be OK for quite a while.

 

Now I'm smelling gas (no overflow) and the idle usually but not always wants to hang up around 2500 rpm. What messes me up is that occasionally it is just fine! (900-1000)

 

I"m finding I don't need any choke to start it.

 

I bought a 2nd carb rack (minus diaphragms and sliders) and I have diaphragms and the basic VMAX ebay carb kit. Just wondering if anyone has any suggestions. Even changing out the carb rack would be a major undertaking for my wrenching comfort level so I'd like to wait for off season to do that.

Edited July 6, 2012 by Trader

[JohnMidnight]

Sounds like my carbs on my 90, the gremlins are moving! Except she'll idle at 2K.

 

No vmax kit, sliders are probably sticking..... But they didn't stick when they were off. Worn, but did not stick

[Yammer Dan]

Vacum leak??

[Trader]

Vacum leak??

 

I sprayed either around the carb boots...no difference in idle

[Marcarl]

What happens if you force the throttle back with the grip.

Maybe you need to clean the linkage a bit.

Is there a choke valve hanging up.

Are all your sliders working? One could have come apart.

 

Try CTC carb cleaner in the tank with less than 2 bars showing. Use the spray stuff, and spray in the whole can into the gas tank. Then take it for a short ride to get the mixture into and through the bowls. Then let it idle for about 15 minutes. Shut it off for about 30 minutes, and let it idle again for about 15 minutes. Do this about 3 or four times to get fresh cleaner into the necessary areas. Process could take up to or over 8 hrs. Then take it out for a ride to clean out the rest of the mixture and fill up with fresh gas. You can also use CRC brand cleaner, it works really good as well. Both clean much better than seafoam.

[Trader]

What happens if you force the throttle back with the grip.

idle still hangs up

Maybe you need to clean the linkage a bit.

Is there a choke valve hanging up.

Are all your sliders working? One could have come apart.

it doesn't seem to be linkage related....from what I can see everything is seated ..not hung up I'll have to pull the breather box to check if sliders are working properly so I guess thats the next thing. Seems odd that I have to do all that (below) after you did such a thorough job last fall ....but what do I know....I will bow to superior knowledge and try Carb cleaner again.

 

I think I might just change out the diaphragms...just because I have them.

 

Try CTC carb cleaner in the tank with less than 2 bars showing. Use the spray stuff, and spray in the whole can into the gas tank. Then take it for a short ride to get the mixture into and through the bowls. Then let it idle for about 15 minutes. Shut it off for about 30 minutes, and let it idle again for about 15 minutes. Do this about 3 or four times to get fresh cleaner into the necessary areas. Process could take up to or over 8 hrs. Then take it out for a ride to clean out the rest of the mixture and fill up with fresh gas. You can also use CRC brand cleaner, it works really good as well. Both clean much better than seafoam.

 

had to add this just so the stupid computer knows I'm adding a reply of suitable length!!!

[raybear71]

Have you checked to make sure your chokes are all closing completely? Just a thought.

[KIC]

One thing I noticed on my 89 is that it ran bad when the airbox was off. Once it was back on it ran fine. So, you might see more issues on it running when you take the airbox off to look at the sliders.

 

I have been battling the poor mileage and gas smell gremlins myself. Good luck !

[Trader]

Again...on my 88

That intermittant overflow is now happening almost always...but NOT always!

I have discovered that it is from the #3 carb (rear right when sitting on it)

 

There were no air leaks as before I pulled things apart I sprayed either and carb cleaner (different times) with no noticeable difference

 

I have the air box completely off and the diaphragm and slider out. There are no holes in the diaphragm.

 

SO...is there an "easy" way to get to the drain plug?

 

Once I drain the carb....and hopefully flush away any obstructions...can I or should I try to blow anything into the float bowl? ie. carb cleaner...compressed air?

Is it possible to adjust the float with the carb on the bike? If so HOW?

[Yammer Dan]

Drain plug is easy access. Lower right corner of carb. You can shoot a blast of air back thru it.

[Trader]

Drain plug is easy access. Lower right corner of carb. You can shoot a blast of air back thru it.

 

I thought the drain plug was on the lower INSIDE face of the carb????

[bkuhr]

I thought the drain plug was on the lower INSIDE face of the carb????

Yes and no

 

The actual drain is the black plastic nipple inside lower bottom face with a hose attached comming out the sides. The screw to open the drain is right there on the outside bottom right. It is a tapered valve type screw that blocks off the drain port when closed.

 

No, float adjustments can not be made without rack removal and disassembly.

[bkuhr]

Once I drain the carb....and hopefully flush away any obstructions...can I or should I try to blow anything into the float bowl? ie. carb cleaner...compressed air?

stole this from the vmax site for idle circuit cleaning

http://vmax.lvlhead.com/tips/shotgun.htm

[Trader]

thanks guys...I'm going to have to find some pictures in the manual to figure out where you mean.

 

I"m just not getting it.

 

See the attached picture...I thought the plug circled in red was the drain plug To drain the float area.

 

this is obviously a set of carbs off the bike and upside down

 

 

I just got a flash!...is it the drain screw I circled in blue?

Edited July 9, 2012 by Trader

[bkuhr]

 

I just got a flash!...is it the drain screw I circled in blue?

 

YES

[Trader]

Well, I finally figured out the drain (can you say Duh!?)

Blew out every oriface I could find, now I'm trying to put the airbox back on.

 

I've been playing around with the one hose that runs from the back of the airbox iinto the case at the center of the carb rack. What a PITA!!!!!!!

 

Is there an easy way to do it? I've tried putting it on the air box....and fishing it thru (closest to success) and I've tried putting it on the center pipe and then mounting the box (not even close to getting it.

 

It would help if I had extra long needle nose....might just go buy some tomorrow!

For tonite...I give up! It's been a long day!

[KIC]

You have the answer !

 

Run to Harbor freight and get the set of long needle nose pliers for $10.00. I just used mine AGAIN today on the 87. They are worth every penny. I bought mine to connect that hose and can't believe how many other uses they have had.

 

I won't leave the garage without them !

Edited July 10, 2012 by KIC

[KIC]

And... don't feel bad. I got the 87 started today after replacing the diaphragms and it still runs like crap. Will put new plugs in it tomorrow but if that doesn't work, looks like a rack pull for me..

[Marcarl]

Hose goes on the airbox, then wiggles down through the carb bank, take some time to figure out just where, it makes a difference. Not over as far as it can go and not in the middle of the works either. The long length goes on the airbox, and the shorter end on the T. You don't need to use the clamps, as once all is in place, nothing can go anywhere. Don't drop the airbox all the way down, drop it as far as needed to sight the air tube from the right side of the bike and then bring it down a little at a time as needed. Loosen the lower faring on the right side and then use the long needle pliers to pull and guide the tube onto the T. Be ready to spend some quality time with your baby, it can take anywhere from 5 minutes to 2 hours to get it on.