HELP, running on 3 carbs!

[Radiation]

I just bought a '80 XS 1100 special. It had been sitting indoors for about 4-5 years. It ran before it was parked.
I changed all of the fluids and filters. I cleaned out the carbs and sealed the tank( POR 15). I put it back together and when I tried to start it I could only start it with the fuel enrichment valve all the way out. I can only let it idle. If I try to give it any gas it would die. I took off the carbs and totally went through them again. I did the wire tie sychro and pulled the plugs to adjust the valves out 1 1/4 turns. I put them back on and it started right up with the enrichment all the way out. The problem is that I cant touch the throttle or it dies. If I put the enrichment valve in to the first setting it barely idles. I still can't touch the throttle. If I try to shut off the enrichment valve, it dies. I got it running with the enrichment all the way out and started tinkering. I found that the #2 carb does not appear to be fueling. I pulled the plugs and I am getting plenty of spark. I even pulled the valve cover to make sure a valve wasn't sticking. Nope! If I cover the vaccum port on the other carbs the bike will die. If I cover the port on #2 carb, all that happens is the carb will pop a little.
I pulled the carbs and went through #2 again. I couldn't find a thing. I put it back on and it did the same thing.
Sorry this is sooooo long! I need help and you guys are the best!

[Ken Talbot]

No doubt you've seen the phrase "triple clean" here on the forum. Some guys get real lucky and get their carbs clean first time through. Sometimes triple is still not enough. There's no easy way to put this, but you need to go through the carbs again. After that, you may still need to do them again until they're truly clean. IIRC, Stickyfingers' count was up closer to twenty before he finally got it right.

[Radiation]

Everything is shiny clean and I have gone through every part that can be removed and cleaned. I even pulled the float bowl to confirm my float adjustments. They are on the nut right on. Is there something I could be missing? Please help!

[Ken Talbot]

An engine needs three things to run: air, fuel, spark.

You can get it running on 3 cylinders with the enricher.

That pretty much confirms that you're getting air and spark. You are also getting enough fuel into the bottom of three of the float bowls to enable it to run after a fashion.

If there's fuel in the float bowls, but it is not getting to the carb throat, something must be blocking it. The trick is finding out that that is.

When you had the carbs totally disassembled for the last cleaning, did you run a fine wire into every orifice you could see, then blast a shot of compressed air or carb cleaner through all those orifices too?

If you stick your finger in through the throat, lift up the carb slides one at a time, then let them go, do they snap right back down, or do they drop slowy?

Have you changed out or replaced any parts?

When you say the float adjustments are right on, what is the actual measurement?

[Radiation]

Yes, I ran a fine wire. Yes, I used carb cleaner AND compressed air. The slides came down farely slow. I checked the diaphrams for holes. I did not know which spot to check for float height, it seems like everybody checks a different spot on the float, so I made all of them the same as the highest one. No, I did not replace with new. When I compared them to the others, they were the same. I know they were not, otherwise I would be riding instead ot troubleshooting. I am trying to keep the cost down to justify keeping the bike.

[mro]

#2 can get stinky

Since you've checked most of the basics, if you have a compression gauge I see what you have, especially in #2.

Float height, I check from the gasket mating surface.

Pull the plug on bottom of float to see if gas is in #2???


mro
btw
seems that I've read that w/o the air box on you can have problems toooooo

[DiverRay]

Bill, when you cleaned the carbs, did you clean the "T" connecters and the screens above the needle and seats? You may have some "junk" blocking the fuel flow to the carb.
The float adjustment is from the BARE carb body to the TOP or highest part of the float. You have TWO floats per carb, and need to adjust each one, so all are the same. I don't remember the setting for the '80, but use the setting the book calls for.
You DID drill out the plug and remove the pilot screw?! The symptoms sound like no fuel at the low RPM range, and that is the pilot circut.
Ray

[Radiation]

If you mean the "T" that the fuel line plugs into, yes. I also blew through it while raising and lowering the floats to assure the needle valves were working. I cleaned and blew out the needle seat screens.
I couldn't figure out, from the book, where on the float I was supposed to take my readings, so I set the other 3 set of floats to the same height as my lowest one. I removed the float bowl from #2 and from the other carbs, with gas in them and they all looked to be at the same level.
I just remembered something. The one thing I did not take off was the brass screw that is on the motor side of the carbs. It is a big head screw that is on the outside of the carbs. When I tried to remove it, I almost chewed the slot out. I could only move 1 of the 4 about 2 turns. They are almost impossible to get to with the carbs bolted together. What does this screw go to? The screws face the middle, in other words carbs 1,2 the screw is facing the inside and carbs 3,4 the screw is on the other side so they are facing the inside also.

[DiverRay]

Bill,

I don't have a book with me, so I can't tell what screw you are talking about. You can look at the Yamaha web site, go to the "parts catalog" and look at a "blow apart of your carbs.
There are some differences between the '78/'79 and '80 on up carbs. I've worked mostly on the early carbs, as both my bikes are early models.
Look for the "pilot jet" on the Yamaha site, and also the "pilot adjustment screw". I'm almost positive this is the problem area you need to address. There are some good pictures in the "Tech tips" area as well.
Ray

[Radiation]

That screw I am talking about is not listed on the Yamaha sight either. It is below the throttle linkage. I know they are a b**** to turn. I guess I will work on it some more when I get home from work.

[Brian_D]

Bill,

I'm at work now and not in front of my bike, but I believe the screw you are referring to on the '80-'81 carbs simply prevents the butterfly valve return spring from moving/sliding off of the post on the carb body - I do not recall it having any other purpose.

[Radiation]

That seems about right from where its located. I know the screws are unbelievably tight. They didn't feel like they were "gunked" tight, just tight!
I am wondering, I keep hearing about pilot screw, pilot jet, pilot adjustment screw, pilot circut. Are some of these the same? I only have so many jets, screws, etc.
Also, does the tube that runs down the middle of the carb, that the main jet screws into, come out? How, and should I remove it? I sprayed the insides of all them out until they were shiny clean, but I want to be sure!
Thanks.
PS.
How do I put my bike info at the bottom with my name?

[TopCatGr58]

Aha.....the truth comes out!!

Hey Radiation,

I am wondering, I keep hearing about pilot screw, pilot jet, pilot adjustment screw, pilot circut. Are some of these the same? I only have so many jets, screws, etc.

This statement tells US all that you have NOT done a thorough carb cleaning afterall!!

Okay, you pull the vacuum slide tops off, and the slides out, and then flip it over and pull the MAIN jets out, and THEN you can push the brass "nozzle" up thru the carb, it has about 16 small holes in it's sides that are possibly clogged!!

Secondly, the Pilot JET is in the tower next to the MAIN jet, and they, too, need to be removed and cleaned. Then the Pilot Screw is on TOP of the carb body, in or on that tube next to the part that mounts into the INTAKE manifolds. Those also need to be removed. And THEN you can spray cleaner fluid thru from the PILOT JET tower/hole and see IF it comes out the PILOT Screw hole and the holes below the Screw location...there are 3 little holes on the inside of the carb throat, in front of the butterflies, on the inside of the top of the throat, and fluid should squirt out thru at least one of those holes depending on from where you are squirting the cleaner!

So....as Knewsome says, "Tear apart your carbs", and get that Triple Clean done!!
T.C.

[Ken Talbot]

Originally posted by Radiation
Also, does the tube that runs down the middle of the carb, that the main jet screws into, come out?

Now we're getting somewhere! Getting those tubes out and clean is absolutely critical. Like TC says, all the little holes in the sides of those tubes need to be clean, and so does the bore that the tubes come out of.

Third time might be the charm, eh?

[Ken Talbot]

Originally posted by Radiation
PS.
How do I put my bike info at the bottom with my name?

Click on the UserCP tab at the top of the page, then click on the Edit Profile button. You'll see an entry field about half way down on the right side for your signature entry.