Carb flooding new member help

[cdavidscee]

Flooding issue

Hey guys thanks for responding but if you read my original post will find answers to most of the questions your asking. I am looking SPECIFICALLY for a reason that someone actually found an answer to in regard to FLOODING as in running out of the bottom of air filter box. Obviously that would not be the fuel T. As for static testing is not needed to figure out that the float is open when fuel is running on the ground. As for pressure testing, I mentioned that I could blew as hard as I could with the carbs upside down and could not blow air past the float needle, turn them over float opens and can easily blow through (not talking about a little fuel getting by the seat when the tank gets hot and pressure builds putting more pressure on the seat). I can shut the fuel off at the tank so the flooding stops, and turn them on intermittently as I ride and the thing runs great and with the new jet kit Sigma) pulls like a bull all the way through the RPM range to 9k. If this was and easy fix I would not be writing. So if you have an idea I have not tried please respond but please read what I have already done first. And as I have mentioned I have already read everything on this site as well as everything on the web I can find as well as every video You Tube. Nowhere have a found an answer to the specific problem I am havingm (which seems unbelievable) (I never been a lucky Guy). As I have mentioned I have ordered new needle valves, cleaned and the seats till the shine like a mirror. I will trim the gaskets next time in but they seem to have lots of clearance as well I will again check alignment of the floats in the bowl. Yes the floats float in gas (like a donut in coffee). Again thanks I don't mean to sound ungrateful but as I mentioned before I wrote to you I have talked to a lot of guys and get a little tired of the "did ya clean em and check the needle seat for dirt".

[Bonz]

Ok, what do you mean in your original post by "...bought the bike and the carbs did not flood" but in parentheses you say "previous owner said he had had trouble too"?

If the carbs are in good order, then you won't have a fuel leak, period. Even if you have an Octy, good carbs will protect against an Octy malfunction.

A leak out the airbox is a leak internally in the carbs, whether bad needle seat o-rings, spec of dirt, bad needle tips, varnished needle seats, float sticking on a gasket, float not pivoting correctly, float needle getting cock-eyed in the tang when inverted on the bike, etc.

Not to sound short back at you, but that's the bottom line.

[cdavidscee]

Off topic suggestions on carb flooding

Hi guys and thanks for responding and attempting to help. When responding please read what I have already wrote, as many of the questions your are addressing have already been tried. Again I am looking SPECIFICALLY for answers to the (gross) flooding issue, not a drip (as in T-line connector). I cannot believe I am the only lucky guy to have had this problem. I have read everything on this site regarding the flooding issue and have not found a solution. I have read Jeffs link and have not found an answer to the specific problem of gross flooding that fits the sinario. As for pressure testing BEFORE putting back on the bike I mentioned in my first post I did the clear hose for visual check of fuel level. This was done with the tank hooked up above the carbs replicating real working conditions (except vibration from the engine running), and besides we are not talking about a little fuel pissing by the needle seat as in the case with a hot tank creating higher pressures and not venting properly. Again as I have already stated I have ordered new needle valves and at that time tirm the gaskets (although there appears to be lots of clearance there as well as the float bowl clearance). I don't mean to sound ungrateful for the advice, but like I said I have talked to lot's of guys and read much and get a little tired of "have ya cleaned em and checked the seat for dirt". And as I 've said if I ride it and turn the fuel on and off to prevent flooding and it runs great, pulls like a bull all the way through RPM's to 9k with the new Sigma jet kit. If there were a problem in said O-rings due to carb cleaner I would be having an idle or driveability issue not gas running on the ground intermittently (along with float stuck closed at time - no fuel)? Thanks again Dave

[cdavidscee]

Sorry for the repeat post

Addressing "please read first post". I said the previous owner said (when I asked him about the current problem) that he had had the problem before. When I bought the kike as mentioned it ran fine (did not flood) but would not go over 6k (started cutting out). I put on a Kerker with hand made glass pack low back pressure baffle and K&N filter, Sigma jet kit 117's 48's , 2 shims, drilled slide per instruction from Sigma. 6k problem solved runs great but developed carb flooding issue. Like I've said been in there 30-40 times tried much no dice. I have moved needles and floats to another carb only to have a different one flood (not the one I just moved). As I've said it is an intermittent problem. I have thought I had found the problem bike ran great for a few miles than after full acceleration float stuck back to flooding, tap on bowl sometimes temp fix. This the exact (as far as I can tell) problem Jeff had and I have not herd what the solution was for his carb flooding. One reply mentions putting in steel rather than rubber tips but most bikes seem to be doing fine with the rubber?

[3Phase]

David,

Remember you're working with gasoline. Don't get frustrated or try to take shortcuts.

We're not just reading old forum posts. At one time or another almost every one of us has SPECIFICALLY fixed fuel leaks that have flooded the airbox. That's involved everything from ignoring it and hoping it will all just go away and stop doing that, to repeated teardowns with much hair-pulling, gnashing of the teeth and wailing.

No, it's not obvious that the fuel tees are not leaking. Check them. Please.

Alright, it's not the fuel tees. From what you're experiencing I still think some of the floats are hanging open and sticking shut.

Take the bike and a fire extinguisher outdoors, then pull the bottom off the airbox, turn on the fuel and watch to see which carburetor is dumping fuel.

If it doesn't leak, hook up the clear plastic hoses to the float bowls, start the engine and do a dynamic fuel level check. Dynamic. That's just like the static fuel level test you did on the bench but it's dynamic. That means do it with the engine running. Slowly work the throttle and watch the fuel levels. The fuel levels should drop as the engine uses fuel, then recover and return to the correct height when the float valves open and close.

Remember you're working with gasoline. Don't get frustrated or try to take shortcuts.

Oh, and don't smoke. It's not because of fire, that's what the fire extinguisher is for, it's because cigarettes taste terrible with gasoline.

.

[motoman]

What the carb gaskets 'look' like IS irrelavent! Trim them on inside as I PREVIOUSLY stated. Do DO that to eliminate that as an issue....one thing/change at a time!....period.(you'll know why as you go forward for resolving upcoming MORE incorrect fueling issues).

[tcoop]

When ever I have drained my carbs to empty then filled them (removed carbs from bike, etc) I get leaks usually heavy flow. I have to tap (sometime HIT) the sides of the carbs (With a wooden handle) for the needle to set. After that they are fine and don't leak, until the carbs are drained again.

[BillyRok]

I've been following your frustrating issue here, did a little search and found this from Motoman last year when somebody was having the same problem...

Flip that carb bank upside down with bowls removed, hook up a fuel supply(tank set above carbs a couple feet), let it set for an hour looking for fuel weeping by the float needles.....easy-peesy. If no leaky, floats are hangin' on gasket edges or float is sinking (leaky float).....again, easy-peesy. No need to overthink it.

Have you submerged the floats to check for air bubbles to ensure they don't have a pin hole leak?

You posted this...

I went and bought pins that were slightly small ID so that they just slide into towers. When I have the bowls off I can blow into the fuel line floats open no problem, flip over floats close completely can't blow through em. Floats seem to have lot's of room in the bowl from side to side. I 'm like Jeff very frustrated.

It would seem that if the carbs are upside down on a bench so the floats are closed by gravity that you would still be able to blow into the fuel line and the air pressure would lift the float but let's wait for the experts to respond. When the carbs are upside down do the floats jiggle up and down freely if you tap on them? You may have an issue that I had --- one of my floats (when the carbs were upside down on the bench) would hit the carb body before the float would close. I had to use a razor knife to scrape away a little of the top of the float so it didn't come in contact with the carb body anymore. Luckily I discovered it before I put the carbs back on or I'm sure I would have had a leak.

I just remembered I made a video ...

http://https://www.youtube.com/watch?v=9iL-OsAC9e4

You may still have a bad needle even though it looks OK, the new ones you are waiting on may be the cure.

One other thought that one of the experts could comment on...I've read threads were there were issues with the carb vents being plugged or fuel lines hooked up incorrectly to the vents...could this be the issue?

Hang in there, it can be aggravating! At least you are at home with carb problems and not hundreds of miles away. If somebody here can't figure this out then nobody can!

[motoman]

In referance to what billyrok statd as far you having new float needles on the way......if they are not from Mikuni, you WILL have issues....again as far as getting RUNNING fuel levels the same on all four carbs.
Some HAVE been fortunate with there use.....majority of time, ainn't gonna happen...period! BTDT! I have actual documentation, not only from me, but others on the Honda ST site that fuel related K&L parts ARE junk!...including petcock kits...don't use the crap, period.
If you use for instance the K&L float needles, and IF they work for you getting fuel levels identical........they will NOT CONTINUE to stay that way!
Hopefully, you take no offense to what I and others have been TRYING to explain to you, but you are NOT going to 're-invent the wheel' here, and advice we are giving is just trying to save YOU the frustrations the years the EXPERIENCED here have all ready been thru. Take our suggestions, ONE AT A TIME, apply them, report back the results, and we'll go from there.
BTW, in all this, 'close is good enough' DOES NOT WORK....period.

[Jeffintampa]

Addressing "please read first post". I said the previous owner said (when I asked him about the current problem) that he had had the problem before. When I bought the kike as mentioned it ran fine (did not flood) but would not go over 6k (started cutting out). I put on a Kerker with hand made glass pack low back pressure baffle and K&N filter, Sigma jet kit 117's 48's , 2 shims, drilled slide per instruction from Sigma. 6k problem solved runs great but developed carb flooding issue. Like I've said been in there 30-40 times tried much no dice. I have moved needles and floats to another carb only to have a different one flood (not the one I just moved). As I've said it is an intermittent problem. I have thought I had found the problem bike ran great for a few miles than after full acceleration float stuck back to flooding, tap on bowl sometimes temp fix. This the exact (as far as I can tell) problem Jeff had and I have not herd what the solution was for his carb flooding. One reply mentions putting in steel rather than rubber tips but most bikes seem to be doing fine with the rubber?

Schimn has my carb, I was were you are at. Then a friend came over to help and broke a post on carb2. My intake valves were major tight if you bike is down right now not really hard to measure and see whats going on, If the intakes are not right may be getting back pressure who knows not me. Schimn has my carbs in pieces and working hard on them, if the answer to my problem you have read about may come. All my intakes will be .20mm and all my exhast .24mm. Carbs gone through and repaired by as close to an expert as I know with these carbs.

Hang tight check your valves.

[mack]

set up

This is my set up for working on carbs. They are mounted on a 2x4 I cut on a band saw and use old carb boots. The carbs just push on and pull off and I can rotate the whole thing so the carbs are upside down.
I sort of do a lot of work on carbs so this is the most efficient set up for me.If they are going to leak, I like to know it before I mount them on a bike and find a nice flamable puddle on the floor the next morning.
Sounds like you have the same type of luck I do, so when you pull the bottom of the air box off, invariably the leaking carbs will be 2 and/or 3 so that tapping the bowl with a screw driver handle is impossible. Been there. Thats why I built the carb station to do the static testing and set the levels properly. I've worked on carb banks for all four years of the XS's, and they will all leak until they are set up properly.

The set off carbs in this picture were off an SF and all four leaked. I played with the fuel levels for days. They'd hold for an hour or two, I'd leave them over night and find they'd leaked when I came back in the next morning. I changed out needles, floats and trimmed back the bowl gaskets, checked the drop tangs and shook and rotated the carbs by hand to check the action of the floats. Nothing worked. I finally just got rid of the K&L seats and needles and put in an old set of mikuni's I had with metal needles. They have never leaked since. Infact I think they might be the set on my SF right now, or they might be the ones I gave to Rob.
If your carbs are 1980, they have the pressed in fuel seats with little o rings. These are held in with a screw and bracket. If you do take the carbs off again thats a good place to check for leaks. The needles may indeed be sealing but your getting blow by the seat itself.
As stated, they will all leak until you find the cause, but they will all stop leaking once you correct it. We've all been there.
Good luck

[motoman]

lol.....Mack, I'm likely gonna do the same with the needles on mine. 'Scuff' the original viton ends removing the seat mark(didn't leak previously, but the o-ring seats did), take the original Mikuni hanger clips BACK off the K&L junk and back on the original Mikuni needles and go thru the running level process again.......that's gonna mean several more carb installs and removal. No biggie though, with the previous dozen times or so in the past few yrs..
Like you've said, best to just 'tap-out' on the K&L junk....unless you just ADORE seeing how fast you can do carb removal and install. BTW, all stock set-up, got that down to 10-12min., INCLUDING fairing lowers removal if they're on there.
On top of that, the K&L junk-crap float needle springs won't hold the same tension after a while from the heating/cooling cycles of the carbs.....wish all the luck though to those who have to 'cheap-out' cost wise for the K&L junk.
Lesson learned for me.

[mack]

2x4

If anyone is interested. Here is a shot of the 2x4 I cut to mount the carbs

The bandsaw cuts were at 22.5 degree's (you only need two cuts) and the boots are 9 1/2 inches center to center. The 2x4 is mounted to the wall with a lag screw with large plate washers on either side so the whole unit will rotate freely 360 degree's.

[mack]

Removal and install

LOL Motoman. I have a number of sets here ready to go, so if I'm doing testing I can have a set off and a new set installed in under 10 minutes. There is a reason the K&Ls are cheap to buy.
cdavidscee: 3 phase was refering to the vent T's. These have been known to cause leaks, particularly if a mistake is made plumbing the carbs and the fuel is hooked up to them not the lower t's. However, if you have 1980 carbs, you will not have vent t's on yours. They are vented through those upper little holes in your bells. Little critters like to build nests in them so if you haven't blown your clear, you should. The bowls need to be vented or the bike will not run properly and can cause a slow seep.

[mack]

Dave

If the leak is at the seat, you wouldn't notice any change in performance while riding. You will however notice the puddle under your bike if you forget to turn the gas off after parking it.