Topic: Newbie needs help w/ checking float bowls

[Suke]

Good morning,
I posted a question earlier in the week stating that gas was leaking from my bike when I started it. It came out very fast, and then it stopped after riding it for a few minutes. I started the bike again last night and the same thing happened. Many of you suggested I check my float bowls and make sure there is no debris blocking the flow. So, this will be my project for the weekend...and it'll also be my first real project on a motorcycle (I just got it a few weeks ago).

I've checked all through this website and printed some great info from the faqs regarding cleaning bowls and measuring height. I also bought a Clymer's manual and have the original owner's manual. I'm armed with all this information, but still have some questions. Everything I've found assumes I understand what they are talking about. Well, I don't have a clue! I have some very basic questions since this is all new to me and I want to make sure I do this properly. So, your answers in the plainest English possible would be VERY much appreciated.

1) Where are the floats? (okay, after you are done laughing could you please tell me exactly how to get to the floats? i know they are in the carbs, but still confused.)

2) Can I do this while everything is still installed on the bike or do I need to take the carbs off the bike? I see the first step is to undo the brass screw/plug at the bottom of each bowl, but can I do this while it's on the bike? Won't the gas then leak over the engine?

3) What materials do I need to clean the bowls and check the float height?

4) A posting in the Faqs, suggest you should have new gaskets since you'll probably need them. Is this true, and if so, can I get gaskets at a local motorcycle shop?

I really appreciate your help with this. I'm totally new to this and trying to learn best I can, although it's pretty intimidating since I want to make sure I don't ruin anything on a 32 year old bike.

Thanks!

[Bob Wessner]

I would like to preface this with, if you find anything other than varnish-like deposits in the bowls, like particles of rust, etc. you should back-up in the fuel delivery system and remedy that as well, such as check the petcock screen, check the gas tank and possibly install in-line fuel filters (small plastic see through things you can get at any MC dealer and splice them into your fuel lines). Note they usually have an arrow on them indicating flow direction. That said..

1) Where are the floats? (okay, after you are done laughing could you please tell me exactly how to get to the floats? i know they are in the carbs, but still confused.)

The floats live inside the bowls. They hang down within the bowls on pivet pins. You will see them once the bowls are off.

2) Can I do this while everything is still installed on the bike or do I need to take the carbs off the bike? I see the first step is to undo the brass screw/plug at the bottom of each bowl, but can I do this while it's on the bike? Won't the gas then leak over the engine?

Some have serviced the bowls, floats and float needles on the bike, but I prefer taking them off, makes the rest of the work easier. If you elect to take them off, shut  off the fuel at the tank, of course, and remove the fuel lines from the carb bank. I use a small can (like a tuna can) to catch the fuel as you unscrew the drain screw. Personally, then I pour it into the lawnmower.

3) What materials do I need to clean the bowls and check the float height?

Some carb cleaner is the best thing. There is a very good chance you will need to go further than just cleaning out the bowls, so I would recommend getting some Yamaha carb cleaner, any Yamaha dealer or multibrand dealer that includes Yamaha should have it. You can try some spray carb cleaner from an auto parts place first if you like and see if you need to dip any other bits in cleaner. If so, then get the Yamaha. I use a small steel rule with a sliding "T" on it for measuring the float height, it is scaled in MM and inches. Available at almost any decent hardware store. Sorry I can give you some insight on the float height as I'm fumbling with my own at the moment.

4) A posting in the Faqs, suggest you should have new gaskets since you'll probably need them. Is this true, and if so, can I get gaskets at a local motorcycle shop?

Depending on how old the current gaskests are, there is a good chance you will need new ones. If they are dried and cracked to stiff, go for new ones. Even with new ones, when you get ready to install the bowls again, apply some pressure to the bowl and wiggle it around a bit before you snap the locking bale bake on.

Good luck to you. I personally don't get along with carbs, I lack the required Zen I guess.

[pmpski_1]

It helps to have a lot of pictures to look at if you don't know how things work. Here are some that I looked at to learn about carb theory and what the insides look like:

http://oldmanhonda.com/MC/Rcarbs.html

This how-to is for a CB750, but you can get an idea of what is going on:
http://www.salocal.com/sohc/tech/carb/carb.htm

More carb stuff:
http://www.motorcycleproject.com/motorcycle/text/newcarbs01intro.html


I was highly intimidated by the carbs, but I knew it had to be done. I wanted a project and I got it. Learn everything you can before you start so that you know what each part does. Take it slow, take notes, and take pictures. There is no such thing as TOO MUCH documentation. It’s a lifesaver if you need it, if you don’t need it then taking notes just re-enforces your understanding of what you’re doing. Label EVERYTHING.

Use the right tool for measuring float height. I marked 22mm on a piece of wood and measured. Now I have to do it again, most likely because I eyeballed it. Precision counts! Find a T-square like Bob said or get a Honda Float height tool from Ebay. I got one of these and will definitely be using it instead of my trusty piece of wood next time.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4554736745&category=35597&sspagename=WDVW

Others may not like inline fuel filters, but until I re-seal the tank I won't go without them. I'd like to have a little more protection from tank debris so that I don't have to worry about tearing the carbs down for another cleaning.

Don't worry too much about ruining anything on a 32 year old bike. You may make mistakes, but think of it as learning to become its protector

Brian

[Suke]

Thank you guys very much for the info. I'm printing it all out and will read through it many many times before starting. As embarrased as I am, I have a few more questions.

1) Now I understand the floats are in the bowls....but where are the bowls? How do I actually get to them when looking at my bike?

2) Is it easier to clean the bowls with them still installed on the bike, or would you suggest taking them off? If I need to take them off, what is the easiest way to do that?

3) Where can I get new gaskets since it sounds like I may need to replace the ones I have? Can I get this at my local bike shop, or will I need to go to ebay for this?

4) Okay, this one seems really basic but still can't figure it out. (No, I wasn't dropped on my head as a baby!) How do you get the bike on it's center stand? There's got to be a simple way to do this and I can't figure it out! Maybe I should've stuck with other hobbies.

Sorry for all the questions, but this seems pretty complicated. Thank you very much!

[Einyodeler]

There are no stupid questions , only stupid people that don`t ask the questions and mess everything up

1)Check your e-mail , I sent you a pdf. file on the Cb350 carbs and how to disassemble - clean and reassemble them.

2) It`s a lot easier to work on them when they are off the bike.

3) Look here in the FAQ section for places to get gaskets or try your local Honda dealer.

4)Standing on the left side of the bike you place your left hand on the tank to steady the bike put your foot on the centerstand and your right hand on the grab bar behind the seat and pull back while keeping your foot on the stand so it doesn`t slide and before you know it you`ll have a perfectly level bike

[pmpski_1]

1. The bowls are the very bottom of the carbs. They (should) have hoses coming out of them.

2. Take them off. First, drain the gas from them. There is a brass screw that is a drain plug. Open this to empty the gas from the bowl. Make sure you have something to drain the gas into. After the bowls are drained, unscrew the bowl from the carb. There are 4 phillips head screws holding the bowl onto the carb. You will need a "stubby" screwdriver or a right angle ratcheting screwdriver to get to them. Once you have the bowl off you will see the float - it is the plastic or brass "puck" that is hanging from the carb.

3. I guess it is kind of unintuitive if you've never seen it done - put the centerstand down with your foot and keep your foot on it. Now pull the bike up and back, like you're trying to lift it off the ground. The centerstand is a pivot during this process.

Here is a section from the Honda Shop Manual that may help you out:
http://solidcitizen.net/SOHC/Manual_Sections/CB500%2004.pdf  (page 42 of the PDF, page 60 of the manual) In the manual they refer to the "bowl" as the "float chamber body". Figure 183 shows measurement of the float using a float gauge.

[TwoTired]

Centerstand easy operation:
Stand on left side of bike.  Left hand on left bar grip to keep bike balanced side to side.

With right foot on centerstand foot actuator, bring the centerstand down to contact the floor or earth surface.  You can place your own bodyweight on both feet now to maintain your own balance.  Use the balls of your foot on the centerstand lever.
Now rock the bike until you can feel both feet of the centerstand is making contact with the floor.  This stabilizes the side to side balance of the bike.
Place your right hand under the seat or grab bar of the bike.  Your arm should be straight and your wrist should be near your  right hip.
Now spread your right hand and your right foot apart as you straighten your leg.  It's a vertical motion like you were trying to pull the bike pieces apart.   Use mostly your right leg as these are the biggest most powerful muscles used for this operation.   
Although the bike will move backwards, this motion can largely be ignored and is inconsequential to centerstand operation, as the bike will move onto its stand and rest there.

The process will take a small fraction of the time it took to read this description.

[Suke]

You guys are awesome! I really appreciate the time you put in to explain and provide all this information to me. It's a completely new thing to me, but this is extrememly helpful information. This is my weekend project, so I'll let you all know how it went. Thanks again! 

[e_b_c]

Einyodeler/Suke,

Would you mind emailing that 350 carb PDF?

Thanks!
evan

[Suke]

Evan,
Sure, I'll send it right over to you.

[Einyodeler]

Hey Mike
I`ve got a set of carbs that I need to clean so I can do those tomorrow night &  take pics of the procedure step - by - step and e-mail them to you.Probably a lot easier than trying to follow the manual.

Stephan

[Suke]

Hi Evan,
Wow, that'd be awesome if you could do that. I don't want it to be too much of a hassle for you, but that'd really be helpful if you're able to do that!

One more question- I am now looking at my bike and see the four black tubes that connect to each carb. Should I leave those intact or unplug them before taking the float bowl out? If I am supposed to undo them, what is the proper way for that? 3 of the 4 have these little metal rings on the tubes where the connect to the carb, and I just want to make sure I don't unplug something I am not supposed to and then have to go searching for a part I broke.

Thanks again!

[Bob Wessner]

If these are the four tubes that extend to the rear and drape over the airbox, they are just vent tubes. If you are just going to remove the carb bowls on the bike, leave them in place. I you are goint to remove the carbs, I would remove these first, just makes things easier. Those with the clips, remove the clips then the tubes should twist off. Put them in a safe place to return them when you are done.

[El Taco]

I'd sure like to see those pictures, if they become available. I've never done a top to bottom rebuild on a rack.

You can adjust the float height on the bike, without removing the carbs. I use a philips screwdriver bit to remove the four screws around the bowl, adjusting one at a time, bowl by bow, staring from the inside carb, then out. An order often 2-1-3-4. Cylinders are 1-4, looking down over the bike while you are sitting on it. I simply eyeball mine. I'll turn the gas on to fill the bowls, then remove one, and note the amount of gas in it. This is all done on the kickstand, seeing as how my bike leans a good bit, and I musn't have all my gas out on the ground. I set each float to fill each bowl just over half way. I've never experienced any problems with performance with this method, and unless you can't get the tang bent back up to lower the float, you really haven't hurt anything, and shouldn't be able to do much damage.

Good luck.

[Suke]

Thanks!

I was actually referring to the 4 tubes that connect to each carb, which I am assuming are where the fuel goes through. They go to the very bottom of each carb. Should I keep these attached or dettach them before I unscrew the bowl? If I am supposed to dettach them, what is the best way to do this?

Thanks again.

[dusterdude]

suke,sounds like the drain hoses for overflow gas,i would take them off.as far as removing them there might be little spring clamps on them,if so,carefully use a pair of pliers and remove them.however,if they are very old they will probably break off anyway,if they do just buy new ones when you put it back together.good luck

[Suke]

So, the four black tubes that connect to the bottom of the carb (I believe where the bowl is) are supposed to be taken off before unscrewing the 4 screws to get to the bowl? I am not referring to the 4 other tubes that go over the back, but the 4 that connect to the bottom of the carbs. I think these are the fuel tubes, but not sure. I just want to make sure I am only taking them off if I am really supposed to. And if I am supposed to, what is the best method to get them unplugged from the carb?

Thanks!

[Bob Wessner]

Gotcha now, yes these drain any fuel that might overflow in the bowls to the rear of the engine and on to the ground rather than just letting it drain on top of the engine cases. Remove them for now, but replace them when you put things back together. And just to be safe, form the habit of always closing the petcock when you stop the bike in the event it does not seal and keeps feeding fuel to the carbs.

[Suke]

This is funny, I feel like I am in the movie Ground Hog Day and everything keeps repeating!  . I keep trying to find out about one set of tubes, but getting answers on another. At least I think I am.

Okay, unless I am crazy there are two different tubes that connect to the carbs. One looks like it comes from the fuel tank and connects to the very bottom of the carb. The other are an open-ended tube that drape over the back that seem to be used when the fuel overflows, and that is where it escapes.

I am trying to find out about the four black tubes that come from the fuel tank and connect to the very bottom of the carbs, NOT the ones that are open-ended and go to the back. The tubes that connect to the very bottom of the carbs, is that tube supposed to be disconnected before unscrewing the carb to get to the float...or should they remain attached to the bottom? If they are supposed to be dettached, what is the method to get them off properly?

Thanks!

[dusterdude]

gotcha,now im gonna leave that to someone else to figure out.

[Einyodeler]

Your tubes that supply the fuel to the carbs stay attached,you won`t need to  remove these to drop the bowls.

[Suke]

Great, thank you very much!

[Bob Wessner]

You have four tubes from the fuel tank feeding your carbs??? My last question also I think.

[smithrelo]

Suke

One word from female - non-mechanical person: I was looking for easiest, most simple trouble-shooting actions for my Bronco Bike's dying, coughing, sputtering, etc. problems.  So I wanted to see if the gas getting TO the carbs  was the problem. 

I just wanted to start with the simplest work first and eliminate things one by one.  (my hope was that the simple thing was the problem..and that turned out to be right!)

I was able to drain my floats via opening the brass screw at the bottom of each one and my BB has performed perfectly ever since.  I did not have to take carbs off, buy gaskets, etc. etc. etc.   I DID choose to have tank acid washed, and I was helped by Gordon to put in the in-line filters, but again, I wanted to ride my bike, rather than work on it...so I looked for the simplest, easiest thing to do to solve the problem.

What I'm trying to say is, perhaps just by draining the floats, you can visually check for debris, and if there is some, you can take the next step, which is check the tank and perhaps have it "acid-washed" and then the third thing is to install fuel in-line filters.  All three of these can be done in about an hour total, no worrying about resetting carbs, etc. 

Just a thought.

Let us know how it goes!

Linda

[Suke]

Linda,
Thank you very much for your suggestions. I will definitely give that a try first since I'd much rather be riding my bike than working on it too. Hopefully that'll fix it, but if not, everyone has provided me with great info so I feel pretty confidant if I need to fix the float height and stuff like that. I will try your strategy first though.

Bob- sorry if I am asking questions that are confusing or not making the most sense, but this is still all new to me. Yes, I see a black tube connected to the very bottom of each carb. They are basically connected at a 90 degree angle to the ground and go directly into the bottom of each individual carb. I didn't inspect the tubes too much, but it looks like they come from the gas tank, so I was assuming these are the fuel lines. I can take a picture of this when I get home since that'll definitely make a lot more sense than me trying to explain something I don't fully understand.

Thanks again!