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leaking carb

13K views 30 replies 7 participants last post by  John Hockbein 
#1 · (Edited)
Hey all,

I have a carb issue I want to run by everyone before I start throwing parts at it. If I don't turn off the fuel when it's not running, it will drip gas alll over the top of the motor. this carb was cleaned and the neddle and seat were replaced by a dealer prior to me buying it from a private party. I have the invoice for the rwork done and it specifically says new needle and seat. today I started it up to plow and while it was warming up, it started running like it was loading up and them just quit. It was flooded, so I held the throttle open and it started up and ran rough until it cleared out some of the fuel. I happened to look down under it and the fuel was pourning out of the hose attached to the bottom of the carb. I assume it's the overflow hose. Is this a needle and seat issue or am I looking at a float issue? when it first started hapening, I called the dealer that did the work and they said if it was something they did they would fix it, but if it was something else I would be charged for at least the diagonistic. My guess is I won't get out of there without spending some money. :cussing:I would like to try and fix it myself.

Thanks for any suggestions.
John
 
#2 ·
Have you checked the float level? Take a clear rubber tube that fits over the drain on the bottom. Pull the drain plug and put the hose on. If you hold it up so that it makes a U with the end a little above the seam where the bowl and body meet then turn on the fuel you will see your float level. The gas will come into the hose but only as high up the U as the level is inside the carb bowl.

Now the question is the spec, I don't remember it off the top of my head nor can I find my manual. Does anyone have it?

I'm guessing either the float is messed up (tang bent)and your float level is too high or the needle is not seating correctly. Could be as simple as a bit of dirt in it keeping it from closing.
 
#3 ·
THE EVEL ONE

The clear tube trick will not work in this situation. If it was running correctly before it started leaking then you have trash in the needle/seat. Trash is not allowing the needle to seat, and allowing uncontrolled fuel flow into the carb. Most likely the cause of the initial problem as well. I'm betting the fuel tank was not cleaned out. Shine a flashlight down in there and see. I rule out the float because it would have been doing it since reassembly. Tell your dealer if the tank had been cleaned properly this wouldn't have happened. IMO carb work w/o a tank cleaning is a 1/2 a$$ job dealer or not. All they did was put a band-aid on a bullet wound. You better keep that fuel shut off as it can fill the engine/airbox/exhaust I'm speaking from experience, you definitely don't want that happening. Trust..you'll see trash in the bottom of that tank, the same trash that caused this problem previously. The only other possibilities would be float/needle/seat failure and that's not likely given recent history....:devil::devil::devil:
 
#4 · (Edited)
Ok, It sounds like I will have to pull the carb. Any hints or tricks to make things easier? It looks as if I can get to it by pulling a side panel. It seems to be mounted to a rubber boot and a clamp. Should be easy enough. I wonder if I should just bring the carb back to them instead of the whole bike. They told me it would take thenm a few days to get to it and I have about a 1.5 hour drive one way to get to the shop that serviced it before I bought it.

John
 
#5 ·
THE EVEL ONE

You will have to remove the needle to spray it out. Since it has just been worked on it may be possible to get the bowl screws out without complete carb removal. Sea-Foam is reccomended as it won't swell rubber parts. I'd check the jets as well. Most likely has fuel in the oil as well, so change it. I run a bit of non-aerosol Sea-Foam from time to time as it stabilizes and keeps jets sparkling clean. Clean out your fuel tank as well to prevent this from happening again....:devil::devil::devil:
 
#6 ·
My vote is trash in the main jet not allowing the needle/float to seat. This happened to a Warrior I had with the same description of symptoms, i.e. only run throttle wide open. In my case the sock filter in the tank was ripped and a little piece of red gas can plastic found its was to the jet. Took the bowl off and opened the petcock into a container and there it was. Be careful not to lose the pin holding the float assembly up or you're sol. Reassemble and at some point put an inline filter between the tank and carb.
 
#7 ·
OK i'm having a little troubel. I decided to remove the carb because the screws in the bowl are super tight. How do I get the throttle cable out. I unscrewed the barrel connector, but howw do I get the cable to release from the carb? That is the only piece left before I can get the carb to the bench. I have enough slack to tip the carb on it's side and I tried the screws. I'm already starting to screw up the head, so I really want it on the bench. What will the trick to pulling the bowl screws be?


Thanks guys.
John
 
#8 ·
Use a small manual impact driver with phillips bit to loosen screws.
 
#9 ·
THE EVEL ONE

Loosen all adjustments and work the barrel out of the slot and the cable should come out. I've found the best removal tool for the bowl screws to be a very small set of vise-grips. Might as well forget the screwdriver, and a change to ss allen heads is a wise idea. Coat them liberally w/anti-seize upon reinstallation and don't overtighten. BTW are you working on a 600.....:devil::devil::devil:
 
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#10 ·
Loosen all adjustments and work the barrel out of the slot and the cable should come out. I've found the best removal tool for the bowl screws to be a very small set of vise-grips. Might as well forget the screwdriver, and a change to ss allen heads is a wise idea. Coat them liberally w/anti-seize upon reinstallation and don't overtighten. BTW are you working on a 600.....:devil::devil::devil:

I am working on a 2000 600. I'm not sure what you mean about working the barrel out of the slot. I have the barrwl connector completely off the threaded piece that goes into the carb. There is a grey piece of cable that goes into the threaded tude that is into the carb. It attaches to the butterfly. when you pull it the butterfly opens. I don't see where I can detach the cable from the butterfly in the carb. I'm lost and frustrated.
 
#11 ·
THE EVEL ONE

I've PMed Jack to your rescue. I've only removed mine once and from what I remember I just loosened it up where it enters the carb and slipped the barrel out of the slot it rests in.The barrel BTW is the piece on the end of the cable that looks like a barrel. Welcome to Frustration Central BTW...I got a headache..............I'm just sayin" Back in a bit>>>>>>>>>:devil::devil::devil:
 
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#12 ·
I pulled the triangular plate off the side to expose the area the cable connects to. I see the barel it fits into and I can partially pry the barel out of the hole it's in, but not enough to release the cable. I must be missing something very simple. There were no scratch marks inside this cover on ony of these parts until I started trying to pry the barel out, so the dealer must have had a better way of removing the cable. I do appreciate the help you have provide so far, please keep the suggestions coming.

THank you
John
 
#13 ·
I do shut it off when I'm not using it now, but yesterday the fuel just started flowing out of the overflow tube, even when it was running. It was actually pouring out under the bike and leaving a puddle when It was running and totally loading up on top of it.
 
#14 ·
You would need to add slack to the cable and open the butterfly all the way to have enough cable to pull the barrell from the lever.

Did you read the previous post?
Possibly you don't need to remove the carb........!!!!!
Thank you I did read the post. it ran fine until yesterday if I turned the fuel shut off open about an 1/8 from closed it still let way too much gas in the carb and would run out of the overflow under the bike. I know the shutoff works because I have the feed line disconnected right now and I'm getting no fuel coming from the shut off. I have all the slack in the cable I can get I even gave mysyelf some from the handle bar adjustment. Am I in the correct place under the triangular cover to pry the barel out of the mount?
 
#15 ·
I think I need to stop working on it and give it a fresh go tomorrow. Maybe a new day will give me a less frustrated feel and IT will go easiier for me tomorrow. Now the question is will I be able to sleep or will I be thinking about it all night? Thanks for all the help guys. I appreaciate the time you have given me.
 
#16 ·
THE EVEL ONE

Trust.....It'll all work out. You are in the right place under the triangle cover. As per Jack's instruction loosen all adjustment. There should be a bit of slack between the cable and the saddle it rides in. If you roll it around to create more slack you should be able to slide the barrel out and then the cable. Be double damn sure to lube that cable and saddle w/lithium grease upon reassembly. You should also take the tank off and clean it out. Also you should change the oil. I'm betting if you check it it will read high from gas that entered the crankcase. Oil thinned by gas is not gonna provide proper lubrication. I cannot stress this enough clean that tank and change the oil and filter. It would be a prime time to install an inline fuel filter as well. I've stated this before trash is the number one cause of trouble w/carburated Grizzs. It is a PITA so keep it clean at all costs. Much more fun riding than wrenching. Yes it will look better tomorrow. We will be watching so post up if you need to.:devil::devil::devil:
 
#17 · (Edited)
I will be working on it later this evening. I have been thinking about it a bit and I think When I disconnected the barrel tensioner on the cable I actually shortened it at the carb. I will re connect it and turn it all the way in to see if I get that slack. I will also change the oil and lube the cable while I'm at it. It's too bad, I just changed the oil and filter about 60 miles ago when I purchased it. Oh well, better safe than sorry. Between this and having to change the belt because it had water in the belt case that froze one cold night, I have been doing more wrenching than fishing or plowing with it.
 
#18 ·
While looking at the inside of the throttle, reach up and work the thumb throttle. See how the cable pulls the barrell and turns the plate? Stick your finger or a tool in there holding it up, then release the thumb throttle. The cable will come back down creating you slack. If you don't get it let me know, I'll go grab a quick vid for you.
 
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#30 ·
:icon_ laughup: To get slack in the cable. Also, make sure the barrel is screwed in, that worked good for John. Don't lost anything!
 
#19 ·
Thanks for the help. I threaded the barrel back onto the carb and that gave me enough slack. Thankfully, I plugged the opening into the jug with a rag, because the barrel came out not under control. I found it on the floor though. Now the next problem is getting the bowl screws out. I thought having the carb on the bench would give me a better angle to pull the screws, but I just ended up screwing the head up more. I don't have a needle nose vise grip, so I will have to wait until after work tomorrow to go to the store to get one. I will try the trick posted previously. Hopefully they will come out that way.

It seems like this is becoming a lot more trouble than it shouls be.... at least next time I will be able to help someone because of all my new found experience.......

Thanks everyone.
 
#20 ·
Those are the devil. I used an air hammer and a homemade tool similar to the Shake N Break form Eastwood. Basically a souped up impact driver. Do you have an impact driver? Hammerdrill? The vice grips will work too. Be prepared for another trip to the hardware store for the replacement allen head bolts. (Take an original with you.)

Don't forget to clean the tank or you'll be doing this again.

You'll get it, just have patience and don't get frustrated.
 
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#21 ·
update. The carb is on the bench and the bowl screws are out with the needle nose vise grip trick. Very Nice! The inside looks pretty clean. I did see a tiny bit of debris on the seat rubber, but barely a spec. There was some gunk around a rubber O ring on the float.. I pulled the seat for the needle and that O ring seemed a bit gunked up as well. I'm a little surprised, because the dealer charged $57 for a new needle and seat. It seems he used the old O ring possibly. I also notice that the seat did not seat all that tight. I did have to put preassure on it to get the O ring back in the hole on the carb, but the brass does not sit all the way down unless I keep preassure on it. I'm not sure if that is normal or not. I wonder if that is why I had so much fuel pouring in? Maybe when the bowl in torqued down that keeps the brass seat agianst the carb? How do I set the float level? Should I assune it's ok? I would have no idea of which way to bend it to make it shut off eariler. I did not want to play with it until I hear frome someone on how to check it for the correct adjustment. Hang in there with me guys, eventually I will get this.... I'm draining the tank right now soo I can clean it. I also picked up an in line fuel filter tonight. That will go on before I fire it up tomorrow.

John
 
#22 ·
I wouldn't mess with the float yet. What is keeping the needle from seating? Watch the entire mechanism and see where it is hanging. It could be a bad needle/seat, but I bet there's just some gunk hiding in there keeping it from functioning properly. Got pics?
 
#23 ·
Inthink the needle is seatjing, but the brass seat it's self is not sitting down on the carb hole without pressure. I spent some time last night making sure everything was very clean. I have put it back together and I am going to re install the carb when I;m done helping the kids with home work. I will post later when it's running I hope this fixes the issue.
 
#24 ·
THE EVEL ONE

Yamaha updated the needle and seat a few years ago. One is brass the other stainless. I'm 99.9% sure the updated combo is the stainless one. I'd test it on the Grizz before I went too far as it is likely to leak. You're gonna need the updated one. The small spec of trash is all it takes. That's all that was in mine. You said the needle wouldn't seat unless pressure was applied. Are you testing under flow..I'm thinking you must be because I don't believe you can get a visual. I'm also assuming the carb is the same as a 660, I believe it is though. Float level is set by measuring off the bowl mounting surface. It can be vague at best. I looked at it but did not play around with it. The manual shows a special tool to measure with. I'm thinking your needle/seat is gonna need replacing as no pressure should be needed to shut off flow. The float sure isn't gonna apply pressure. This is a pain believe me I've been there. You must insure the tank is clean and stays that way. I also check my fuel jug regulary and if trash is detected I throw the last bit away. Mostly I fuel straight from the pump now and there's no way to moniter trash from the pump unless you install a filter.
 
#25 · (Edited)
2nd update. I put everythig back together. I also included a clear fuel filter. The fuel flowed into the filter with gravity, but it was not enough to fill the filter. It started right up and more fuel flowed into the filter, but still not enought to fill it up. No leaks at idle and it ran fine after I adjusted the throottle cable to give it more slack so it could rest on the idol stop. I drove it around the block. IT's about 1 mile around. I also finished the plow job I started eariler last week. I parked it in the garage and looked it over well before putting the side covers back on. It all looks good. I decided to start it agian and it would not start without the full choke. Not good since it was running for at least 20 minutes just before that. I pulled the side cover and the fuel filter was empty. I could not start it and get it to draw fuel. I pulled the filter and it started and ran fine. I think the primary issue is fixed.

Now I have to figure out what size filter I should pick up. Would a small filter that a garden tractor uses work?

I want to thank everyone for all the help the have provided me and especially for sticking with it when I got frustrated. Now I will be able to do this job in my sleep if I need to clean the carb.

Thanks Everyone.

John
 
#26 ·
Awesome! Way to stick with it and to know when to take a break when you needed to. My local parts shop sells a couple filters but I'm not sure what they are called. You have to be careful with gravity fed systems or you'll restrict flow (like you saw). I haven't done a filter install, tried one on my '50 Farmall Cub though and had the same results you did. If you haven't found anything by Tuesday I'll check with Ken and see what he sells.

Good job!
 
#27 ·
It seems as if this issue is back at the needle/seat(needle valve set) operated by the float. If it is dirty, it won't seat and shut off fuel allowing fuel to escape out of the fuel bowl at the float chamber vent hose. If the float "tang" was bent, then it may not shut the fuel off even if the needle/seat are clean resulting in the same fuel leaking out of the float chamber vent hose.
Not sure why the whole carb has to come out, but mine is on a 400 and was able to work on the left front fender when I cleaned serviced mine.
If you rule out the needle/seat as the problem, then I would focus on making sure the float is set correctly to ensure the presure is applied to the needle/seat to close off fuel. Throttle adjustment will definitely flood the engine, but don't know that it will cause fuel to spill out of the float chamber vent hose. Just my opinion!

Good luck! You'll get it working soon, and be back riding!:banana:
 
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