UPDATE! Gas out bottom of airbox

[qbrainerd2]

Ok, so here is everything I know so far. I took off the bottom of the airbox and fired the bike up to see which carb had the gas coming back out of it.
It is the number 4 carb and it just pours out.
So I tore out the carbs (careful to snap a few pics along the way to make sure all the tubes got hooked back up correctly). I took the bowl off the 4th carb to check the float valve and found it what appeared to be a little sticky. Once I pushed it in, it slid in and out nicely. I went ahead and tore that carb down and cleaned everything, although the only noticable dirty thing was the little tiny screen. There was a decent amount of setiment on the outside of the screen.
I went ahead and took the bowls off the rest of the carbs to see if the floats were working properly and they appeared to be. I cleaned all the resovoirs with carb cleaner, put ti back together and crossed my fingers. No such luck. Fired it up...still pouring out of the number 4 carb.
Now here are a couple of things I find interesting, but not knowing how the octupus of tubing that is the fuel system works, these could be perfectly normal

A. The left side petcock leaks slightly out of the tube ports when in the "on" position and the "off" position

B. With everything hooked up except the bottom of the air box, if I have both petcocks on and turn one of them to off, gas flows freely out of the #4 carb, same as when it is running, until I either turn the other petcock to off or turn the one back to on.

C. I pulled all 4 spark plugs and found all to be carbon-fouled. Numbers 1 & 2 were dry...numbers 3 & 4 however were real wet. In fact, I even had a little fuel leak out from the block side of the carbs from the boot connecting on #4 when i was moving the carb pack a little

I am kind of stuck at this point. I am unsure what the next step should be.
Are the carbs still my main focus?
Should I look at a possible tie-in to something up with the pet cocks?
Could it be something else entirely?

Remember, this came on SUDDENLY. I ran this to and from work on Friday, filled up when I got home, parked it in the garage Friday night. Jumped back on Saturday night and fired ti right up. I didn't let it warm up , just took right off. I could tell from the start it was not running right. It felt all bogged down. then I smelled gas when I stopped and the rest is history.

I need to have this bike up and running by Friday so I can take it on my weekend getaway, departing Friday evening

I REALLY appreciate anyone's input. Thank you!!

[prometheus578]

Profided that no grit nor rust are coming down the tubes from the tank...
You sir, need new float needles.
Look at the tapered tips of the needles. See that little "wear" groove? That little ring? It's no longer sealing properly, hence the flood of fuel.
Nead down to the local motorcycle shop and buy four new needles. Probably will run you $5 per.
remove the seats and take off the screens. Use some Q tips and chrome polish and polish up the insides of the seats. flush out the system with spray carb cleaner. Put back to gether(don't foget the screens.)
Leave the bowls off, and set the carbs upside down.
Hook up a fuel source. "Blip" each float to clear the lines of air, and then dry up the gas and watch for leaks.
No leaks? re set the float level adjustment and put the bowls back on.
yurn the carbs right side up and do the test again.
No leaks...? mount them back on the bike.
(Don't bother wasting your time trying to polish out that little wear ring on the needles.... you'll never get it perfect enough to seal right)
Octopi I'm not familiar with. Even if they leak fuel to the carbs, the needles should be able to stem the tide. Even on a Standard with the petcocks on prime, you should be able to leave it like that and not have it leak any appreciable amount.
Check your oil for fuel contamination. Has your oil level risen due to fuel from the carbs running down past the pistons?
hell, when was the last time you changed your oil, anyway?

[skids]

I wouldn't change the oil yet unless it is real contaminated...but I wouldn't ride the bike or run the engine hard until you sort out the carbs: You would just have to change it again if you fail on your next try.

1. If the float pivot was sticky, it must be cleaned.
2. I see you have an 81 special. That means you need to replace the O-rings around the float valve (aka float needle seats) if you haven't already done that.
3. Just take those itty bitty screens and pitch them out! Use inline filters and replace those fuel hoses to the carbs if they are originals.
4. Have you sealed your tank? It it full of corrosion scale?
5. That petcock that drips should be fixed. You can take it apart, rebend the wavey washer, examine the holey gasket, polish the valve handle where it seats. I have never tried this on the octopus (I own standards), but I think I would try reconditioning the octo. There is probably an o-ring that seats in a conical oriface. The o-ring could be replaced and the cavity polished (mother's milk of course).
6. Check your float, while you have it out, to see if there is gas in it. This is not likely in the plastic ones BTW.
7. Before you button the bowls back on, with the rack of carbs upside down, blow (not with compressed air or you could damage the floats bulbs) into the fuel hoses to check for obvious leaks. You can also hook up liquid to the hoses and check for small leaks.
8. Make sure that the float does not contact the sides of the bowl. There is not much clearance in there.

[qbrainerd2]

Now, now I'll have you know I changed my oil & filter approx 2200 miles ago, thank you very much

In regards to Prometheus' post, there was at some point some crud coming down the tubes, because I found a fair bit of crap when I pulled out the part with the little dome screen on it. I found what looked like little bits of rock or maybe it was chunks of rust or something. Either way there was quite a little bit of stuff, but all on the side of the screen opposite the float needle.
I can't say that I did a close inspection of the float needle looking for damage on the tip, but I did look it over pretty good and do not recall any grooves or anything in the needle from the carb that I tore down completely, #4, which is where the gas is coming back out in to the airbox from. Would it be really obvious or very subtle?

I honestly wouldn't begin to know enough about bikes and carbs to disagree with you, and I do not mind the small $$ or the work, but my only question would be that it came on so quick and in such volume. I mean when I start this thing up without the bottom of the airbox, the gas just pours out of the #4 carbeurator in probably close to a 1/16" or an 1/8" wide stream. Is that typical of this issue?

Again to Prometheus and all who might also weigh in on this, thank you and thank you in advance.

Q

[prometheus578]

I change oil every 2,000, but let's first sort out the fuel problem.
As fer da needles.... those screens screen the big debris, but what about the smaller stuff... the small particles that get past and slowly erode away against the needle seating surface?
Those wear grooves can be/seem very minor. Sometimes I've had to use a magnifying glass to point them out to customers on the metal type needles. Vitron tipped needles, same thing. Replaced them, and problem solved.

Is that typical of this issue?

Yes.
As your bike is an '81, you have different carbs than I do. You have the vitron tipped needles, replace them. You also need to ensure that the vent for the bowl is not clogged. Early carbs have a hole that vents upward... meets the other carb's vent in a "T" and then hoses to the airbox. Your carb has what appears to be another air jet in the "intake" side of the carb. Looking into the mouth of the carb... on the intake side, you'll see 4 jet orifices. From memory, I believe the bowl vent orifice is the upper right hole. Get some carp spray and make sure it blows through into the bowl area. If you're running pod filters, some people report, with different brands, that part of the rubber lip of the filter can obscure those holes. If carb vents are plugged the floats won't rise properly and the neddles wont seal.
Skids is correct that the float needs to move freely, no stickiness.
I happen to like those little screen. (Am also a believer in in-line filters.) Debris will be rust or grit from the tank, but also can be chunks of rubber from deteriorating fuel lines. Might as well replace them, too. They're twenty years old.
Yes, the O-ring... when doing the bench test, upside down with the bowls off, you can see where the leak is coming from. It's not often that it's the O-ring/gasket for the seat, but I have seen it happen, hence the reason for the bench test, and Skid's mention of them.

check the float valve and found it what appeared to be a little sticky. Once I pushed it in, it slid in and out nicely

I can only imagine that you're referring to the little pin that sticks out of the float needle. Replacement will cure that.
Not having any Specials, I'm not as fluent as others concerning the design or the octopus, but the same minute grit that wears the float needles also erodes the sealing surfaces and presumably O-rings in your petcocks. I believe rebuild kits are available.
These are the common remedies for the most common problems. Hard to fix things from memory... especially without the carbs sitting in front of me.

[qbrainerd2]

The Latest...

I tried to get replacement needles at the local Yamaha shops yesterday, but nobody stocks them. They are about $30 per, which is a set with the needle and the seat. I asked for just the needles, but they said they are not available that way. $120 if I wanted to do them all. So obviously I want to make sure those are necessary before I drop the buckaroos.

I dropped the bowl off of carb #4 and found the float needle stuck open. It gave a little resistance but popped back up where it was supposed to be and moved fine once it was back right. This is basically the same way I found it when I took them apart originally.
I remember someone saying something about a possible adjustment that may be allowing the float needle to come out of the seat too far and get cocked open. That certainly appears to be what is happening. When I seated it manually ti stopped the flow of gas, so I am leaning away from there being a wear problem. Now I have to figure out what is allowing it to come out so far that it gets cocked off center and won't slide back up in without assistance.

Any ideas on that? Is it an adjustment to be made or parts that need to be replaced or both?

I fired it up and the #3 carb started leaking gas back, but I tapped the bottom of the bowl and that stopped. So I put it back together and took it for a spin. Got a mile down the road and it started to bog down again. I drove it back home and it is leaking gas again out of the airbox, so I am guessing the float is stuck open again, probably from a bump on the road or something. It was too late to take it back apart last night.

Then on top of all that I found that one of my exhaust pipes that was cracked is now officially broke. I rigged that back together, but will have to get that welded at some point.
But when messing with it i noticed a lot of oily residue around where the break is. And when I was revving the engine in the garage before I took it out, I was getting a lot of smoke out of the right side exhaust, which is a relatively new phenomenon. Smelled a lot like burning oil. Could it just be burning off excess whatever from the gas leakages or could i have messed up my piston seals if the gas leaked past them.

I wish I knew more about this crap, but I will rely on all of your expertise to assist. Thank you in advance!

[prometheus578]

"Nobody stocks them... bah!"

Common for Yamaha's, some Triumphs and Suzukis, but only for one Kawa(and that's an ATV) No Honda applications.
Check with any local "independant shop", one that works on all brands, of any age.
In not on hand, have them order from the K&L parts distributor... part # 81-8944. Comes in a packet of five. Like I stated, should run you about $25 or so, but could be a little more, depending upon the shop.
You shouldn't need the seat, just the needles.

When I seated it manually it stopped the flow of gas

In that case, I'd say the needles are still good.
Now then... yes, the floats can drop too low. And when they come up, they push the needle up at an angle and it can bind.
There was a great pic of this a few months back(John supplied, but I could be mistaken)
There is a tab on the float... not the one that is used to set float height, but another tang that will hit against part of the float post. This can be adjusted to limit float travel(hanging down too far.)

i noticed a lot of oily residue around where the break is

Probably not oily residue, but due to the flooding of XS fuel, this mess is gas mixed with carbon from the exhaust system that is leaking out.
The smoke is probably due to the extra fuel in the system, should go away after everything is sorted out. Any crap in the header pipes will take a while to burn and dry out, too.

[qbrainerd2]

other related issues???

First, Prom, thank you for all your help on this so far. I hope I am getting close to a solution and I really appreciate your assistance. And thank you to all else who have weighed in to this point.

Here is another ?related? question:

If the petcocks are working properly and the octupus is doing its job (not allowing fuel to flow through unless vacuum is present, as I understand it), when I remove the bowl from one of the carbs and displace the float needle, should I have gas flowing at all? I am wondering this because when I pulle dthe bowl last night, I indeed had gas coming out. I would not say in volumous amounts, but enough to make me notice, and wonder.
And if gas is not supposed to flow in that moment, could that be part of my problem, or could it have, over time created whatever problem in my carbs that I am currently dealing with (wish I could put a name on it )

Just a thought I had as I have been going over this non-stop in my head for the past 4 days. I am going to dig back into it again tonight later and am still trying to figure out which direction to start from, i.e. pull the carbs again or disassemble the octopus or the petcocks or or or maybe all of the above.

Thanks again in advance...

[JWSanders]

Yeah, if your petcocks are working right it'll stop it there.

If the octy is working right, the gas will stop there.

If the carbs are working right, then it almost dosen't matter if the other two are bad, because the gas will stop there (where it needs to be stopped the most). If you're pouring that much gas out it's got to be making it run pretty rich as well.

I was able to get my petcocks rebuilt and working properly using kits obtained on Ebay, but the rebuild kit for the octy was not up to the task.

You can get rebuild kits for each carb for less than what they quoted you for the needle....

Take a look at partsnmore.com

They have a $35.00 minimum order though, but I'd be willing to bet you can find $35 worth of stuff you need there. They have a pretty good range of parts. Shipping is flat at only $3.00

You know, I hadn't noticed that they have a replacement for the petcocks (with an adapter) there now too.

[blkryno]

fuel out of the airbox

Hi all,

this may sound kinda of simplistic but on my 81 1100 SH I found that the no 3 carb was doing the same thing intermittently checked like everyone says above. ended up finding a small amount of corrosion inside the hinge hole on the float where the mounting pin slides through. ran a very small piece of 0000 steelwool through there a few times and the float stopped hanging up . My bikes been put away for 21 yrs so I just put new needle and seats in all carbs anyway. A petcock rebuild kit made a huge difference on the fuel flow. I know mine has been sitting along time but the petcocks were acting like they were on prime all the time.

don't fall down

Keith

[TopCatGr58]

Missing photos found!

Hey Qbrainerd,

I found the thread with the photos, it's HERE ! It was MIKE F from across the pond/UK that posted it way back in 2005!!
T.C.

[prometheus578]

"My apologies to Mike F."

I remembered the picture... especially the nice little arrows.
Now, I know that John isn't that talented, but I figgered that Wildkat did the artwork for him.

when I pulle dthe bowl last night, I indeed had gas coming out. I would not say in volumous amounts, but enough to make me notice

Could that just have been fuel drain from the line?
Disconnect the fuel line on the carb side from the octopus. It if drains from the octopus exit tube, yeah, it's the octi.
If it's hangin' floats, then yes, you'll have to pull the carbs.

[qbrainerd2]

Well, I think I have a variety of things going on currently, but I think the biggest culprit is hanging floats.
I went ahead and pulled the carbs again last night (gets easier every time, but not faster).
I disassembled the octi, very carefully (thanks for the heads up in previous threads). There was quite a bit of rusty corrosion sort of garbage on the vacuum side, after I pealed the diaphragm off, so I cleaned that up and cleaned up the diaphragms well. No tears or noticable blockages so I reassembled.
I did the quick fix on the petcocks that has been mentioned previously (bending the wavy washer). Did the trick on the left side, but the right side still drips a tiny bit in the "off" position. Since it was already nearly 3am, I decided top let that slide for now.
Once the carbs were off, I went ahead and pulled all the bowls, floats and needles. I pulled the screens I had been too lazy to clean the other night and found quite a bit of crud, just like the #4 had. Looked like a combination of bits of grass and even some sandy looking granules. Replaced the screens, needles and floats on 1 & 2 and made some adjustments on the float heights. They appeared to have been set around 22mm, so I reset at 24mm to see what happened. I tried to bend the little tang on the floats on #'s 3 & 4 to see if I could keep them from hanging up, per the previous post (Thanks TC!) The pics appear to have different insides than mine, but I got the basic idea. I put everything back together and adjusted the floats on 3 & 4, reassembled and reinstalled the carb pack.
Crossed my fingers, fired it up , and sure enough had a steady stream of fuel out the back of the #4 carb. I went ahead and tapped on the bowl a half a dzen times and the flow stopped. Took the bike around the 4 mi block. Ran great! never bogged down or anything. Made it home and there were no drips out the airbox. I am going to take it out a couple of times tonight to see if it gets cocked in there again, before I take it on any long trips.

SO at this point, if this holds for a bit, am I going to have to replace the float needle and maybe the seat in the #'s 3 & 4????? down the road. I did not really see a wear groove, except maybe a TINY one on the #3 needle, but nothing noticeable on #4. The sides of the number 4 float needle looked a little beatup, but other than that...maybe that is what is causing it to bind up.

I will let ya'll know how I come out after I ride tonight. Thanks again for all your help as I continue to care for this issue.

You'll have to forgive me if any of this looks like the ramblings of a drunk sailor..I am currently working on just over 2 hours of sleep last night, and not too much more from the rest of the week

[prometheus578]

Did I read correctly? You replaced the needles on #1 and #2, but not on #3 and #4... the carbs that actually leaked?
Did you polish the seats with chrome cleaner and Q tips? If the side of the needles seem rough, sand them smooth.

[qbrainerd2]

Sorry...2 hrs of sleep apparently made me ramble...

When I said I replaced them, I was saying that as part of the process that I went through last night, i.e. I removed them from the carb and then put them back...but the originals, not new ones...sorry for the confusing verbage...

about your notes...no, I apparently do not think well when I am working tired. It never even occured to me to polish the seats while I had them out...also, how fine of a sandpaper should I use to smooth the needles?

Did I mention I despise pulling my carbs out? Just checking