| Author | Message | ||
     Gmc310 |
Admin please move if not allowed. Trouble with an old Katana 750. Bike was flooding last year and I let it sit for a few months. Took it apart and replaced the float needles and reset float heights. Changed plugs and fuel lines. Started right up. Checked each pipe on header to make sure all were heating up. Moved bike out front, wouldn’t start again. Weak battery and not much gas, threw it on the battery tender. Tried in the morning and started right up. After work added four gallons of gas, wouldn’t start and filled the air box full of gas. Petcock has been rebuilt and doesn’t leak when tank is off of bike. Floats should be good. Battery is probably past its prime but seems to turn over pretty strong. Not sure why it’s flooding, could the weak battery cause weak spark and not igniting the gas being sucked in? I did try for a couple minutes to start it. Any help is appreciated. Again. Move or delete if not allowed. Thanks in advance. | ||
| 2003xb9r |
Hi, yes a weakened battery will cause hard starting. Low volts at ignition coils during cranking will make for a weak spark. | ||
| Ourdee |
Re-check float heights and check needle seats. | ||
| Gregtonn |
When you replaced the needles did you check the jets for cracks? Had a GS550 sit for a couple of years and it showed similar symptoms as a result of cracked jets leaking. G | ||
| Gmc310 |
Gregtonn. I inspected both jets and cleaned them with pins. Didn’t see any cracks | ||
| Torquehd |
Rule of thumb, you've got to have a good battery. There are a good handful of problems that can cause poor starting, and a weak battery is one of the first few variables you want to address. How do you know it's flooding? what exactly is it doing? Fouling plugs, exhaust smells like gas, do you hear normal combustion occuring? Will it start when hooked up to a battery charger set on high/or/50amp? (btw i would check an old battery on 50 amp but never a new battery) Edit. The only way to tell if lead/acid battery or AGM battery is bad is to load test it. You can do this by cranking the starter with a voltmeter across the terminals. Static,It should hold 13+ VDC after charging for awhile. When you crank the starter, if the voltage drops below (I believe it's 9.5 or) 10 VDC then it's only got a surface charge. If it's AGM or maintenance free, it needs to be replaced. If you can add distilled water, try that. Or just get a new battery. It sucks sometimes but it's a sure way to eliminate that variable. (Message edited by torquehd on June 07, 2019) | ||
| Torquehd |
Also you could walk us through step by step. Example. 1. bike has set for 24 hours on the charger 2. disconnect charger, bike has 13VDC. I pull the choke knob, turn key on, ingition switch to "run" and crank engine. 3. After 10-15 seconds bike "fires" but doest not start. Exhaust smells like gasoline 4. After several iterations, plugs are fouled. Walk us through each detailed step. It's hard to diagnose through chat. Paint a detailed picture. | ||
| Adrenaline_junkie |
".....filled the airbox full of gas....." Sounds to me like you should revisit the floats, float needles and seats. | ||
| Gmc310 |
A few more details. Never checked actual voltage Both times I got it to start was after an overnight trickle charge. Haven’t tried to start it with extra amps due to my simple trickle charger Didn’t notice extra gassy smell from exhaust. Tried to start for two minutes. Went inside. Got out of shower and smelled gas inside my house. Looked out window to see puddle of gas and still leaking from air box drain hose(that’s what I meant by filling up air box) As far as float needles and floats, I was pretty confident about my adjustments and how they seated. I’ll swap out the battery today and give it another try. Thanks so much for everyone’s input, I’ll be a better mechanic when this is squared away. Thanks | ||
| Sifo |
If it's leaking out the air box after sitting a while, it sure sounds like gas is getting past the needle valve seat. It's an old bike, and vibration can take a toll on both the needle and seat, or it could be a stuck needle valve due to dried gas (ethanol is terrible to store in a carb), or other debris. | ||
| Crusty |
It sounds to me like one of your floats might be filling with gas, or it might be sticking. That's why it starts after sitting overnight (I assume the petcock is off), but won't start and run after a couple of minutes of having the petcock turned on. A sunken float can drive you nuts. Or it might just be sticking a little. How does the inside of the gas tank look? if there's rust, a little rust can cause a problem if it gets into a carb It can cause the needle valve to not seat, the float to stick or it might even block a jet. If the battery is strong enough to crank the engine vigorously, then the symptoms points to fuel. Even if the battery is junk, gas should not be leaking from the airbox. | ||
| Ratbuell |
+1 on a pinhole in a float. A sunk float will let you fill up with fuel quickly. If you can solder, drill a small hole in the top corner of the float. Blow into the hole you made. If you can blow through the float...it's got a hole you need to solder shut. Find it, fix it, and solder up your test hole. Or...just buy new floats if you can. | ||
| Ourdee |
After this is all sorted out; Check oil to see if it smells like gas, Replace oil if it does. Replace spark plugs. | ||
| Gmc310 |
I should mention that this trouble all started last season when my gas lines blew, I stuck it in the garage for a couple months before swapping out the lines, I did nothing but swap out the lines for new oem lines. When i put new gas in I had the same flooding, leaking out of the airbox and gas in the oil. when cleaning my carbs last week I found the stuck float which I though was the issue, the lower inside of the carbs looked great imo with the exception of the stuck float, I replaced the floats and all lower orings, didnt see any cracks in the floats and was surprised that none of them seemed brittle | ||
| Gmc310 |
tank is clean btw, Thanks for everyones time | ||
| Aesquire |
Yamaha 750 triple had a leaky peacock ( vacuum operated ) and filled the crank case. Bike would start & run briefly, then puke gas out of airbox. Even an inch of gas would come out airbox after short trip down road & keep running. I found torn diaphragm in petcock after dousing legs & bike in gas half a block from the house. Your problem sounds different, but check the oil anyway. | ||
| Gmc310 |
Ok Fellas, took all the advise into consideration and disassembled AGAIN, carb floats were NOT sealing, I found that the float needles themselves were too short, this was the most expensive parts unlimited rebuild kit BTW, small carrier clip on top of float was hitting before the float could seal.I actually filed off .020 from float housing to get the clearance that i needed, Now the floats seem to seal nicely, I'll reset float levels again and put it together, Thanks all for the help especially noting that I no longer have my Buell. Class acts all around, Thanks again | ||
| Ourdee |
Riding is riding even if it does look like a goat 20 bucks is 20 bucks | ||
| Natexlh1000 |
"Leaky Peacock" sounds like a good name for a band. | ||
| Ourdee |
Or a bad symptom. |
