Topic: Start up after winter hibernation Update 3/30... FIXED

[Tews19]

I started up my gold K1 a few weeks ago and she started right up. There was a stench of gas but I didn't pay any mind to it until today. I picked up my battery and started her up again. This was the second time since I shut her down for the winter. This time the stench was back. I looked down and there was a puddle of gas. I turned her off and pulled the bowl on carb 4. I made sure the floats weren't sticking on all the carbs. Gas was coming out of the airbox. I checked all 4 pipes and all were hot.

My question is it normal on the 750s to be like this after months of sitting? What else should I check to see why gas is coming out of the airbox? It is 9 degrees and could this play a role with the rubber o rings in the carbs?

[Greggo]

Probably just a sticky float valve...

[iron_worker]

Yep. The fuel level is going up so high it's flowing into the airbox through the carb throat. It also could be going into the engine so best to sort it out straight away.

IW

[flybox1]

^+1
check float valve operation and for a bit of debris preventing it from closing.

[ekpent]

I will say Nick that I had a problem with gas coming out of the carb throat on the airbox side once and fiddled with it.I seem to recollect that it was because the over flow tube,the rubber one,was plugged and something was not venting correctly. I remember Terry from AU concurring and saying he had the same problem once.Gas should overflow there anyways before going in the airbox one would think. Just something to check if its not your float.Speaking of which do you still have brass ?  Might want to make sure its still good and not leaking in gas.

[flybox1]

^ absolutely 
the overflow vents are there to prevent gas from flooding the engine/airbox, and the reason they didnt, needs to be discovered.
the issue of why the float valves are not working, needs to as well.

[kck3]

I'd check your floats. Might have a hole in one of them. That was my issue on my k1.

[Gordon]

My K1 does the same anytime it sits for more than a couple of weeks.  Always has, always will.  I've tried everything to keep the floats from sticking, even hand-polished all the float hinge pins, but it still happens.  When I know it's going to happen, I just keep a screwdriver handy on start-up and tap on the sides of the float bowls as I open up the petcock.  This has never failed to stop the overflow and it doesn't happen again until it sits for a long time, and since it's predictable and easy to remedy, I just chalk it up to one of the quirks of riding a 42 year old bike. 

[KC_Northstar]

I had the same problem with my SL350 K1 and my CB750 K2.  What I discovered was that in both cases the
petcock was leaking in the off position.  If my bikes sat a long time there was always a puddle under them.
This was even with rebuilt carbs.   I installed new petcocks on both bike's - never leaked again.


KC

[Old Scrambler]

Nick.........relax and let the bike hibernate until you (and the weather) are ready for a ride. The one thing that cold  metal needs is a short-term warm-up only to go back to the cold condition. The old fuel will be slightly sticky and tends to make things worse. 

All good advice above Just put it in proper order...........starting at the petcock.  I will add one thing........one or more of your bowl-gaskets may be touching a float. 

[Tews19]

The weather here has finally started to be more like spring. This has allowed me to spend some time on my Gold K1 before riding season is officially here in Wisconsin...

Now on to the scenario....

Carb 3 keeps spewing gas....

I checked the float level on #3 and the rest.     All are the same...

I made sure the float is not sticking to the gaskets... They are not.

I kept trouble shooting to where I have swapped out the floats from a non leaking carb to the leaking carb
, changed out the float needles on the carb bodies and even the gaskets.... Yet #3 continues to over flow...

I have no idea what else to do but to take them apart and reclean... It doesn't make sense due to me swapping out the parts from one carb to another and yet the same problem exsist with #3....

Any ideas?

[ekpent]

Is it leaking out of the mouth of the carb towards the airbox side still. As mentioned before when it happened to me once it was a clogged overflow tube,the actual rubber hose that attaches at the bottom of the bowl. Blew it out and problem went away. Maybe I was lucky or it was a coincidence bet I felt it was the carb having some kind of a venting problem.

[Tews19]

I pulled every bowl and used the air compressor to clear out the vent lines and vent on the bowl itself. Still over flowing.

Tomorrow am I'm going to put on carbs from the other K1 on to see if the problem happens with a different set of carbs.

Side note- All pipes were hot. So no fuel starvation.

Eric- Once the bowl was full of gas it would come out the airbox again.

[ekpent]

Off topic Nick but check out this guys extra parts. See a gold sidecover in his stash.  http://forums.sohc4.net/index.php?topic=119631.0

[bjbuchanan]

Try the other rack if you have a good one in positive working order, if they work well keep em on

Then go thru the problematic rack and see what is the issue. It is gonna be a sticky needle, bad float, possibly oddly swelled gasket or junk n the carb despite a treatment

[Rigid]

Flowing into intake has to be leaking petcock when closed, plugged drain line/ tube, and leaking float needle.  Takes all three.  2 other common leaks are cracked copper drain tubes in the bowl and orings between carb bodies at inlet. 

[kghost]

Does it overflow when stopped, when running, or both?

Doing it while running could be a blocked bowl vent. Not the one on the bottom. The ones on the side (2).

If it does it when stopped I have found that a quick lapping of the float needle to the seat will often cure the overflow.

I've used a touch of valve lapping compound on the needle while giving it a few spins in the seat with light pressure. Clean out the compound then reassemble.

Rubber, steel or brass needles....doesn't seem to matter....a few spins in the seat and the leaking stops

[Tews19]

I took the carbs off this morning to box them out and send them off to our very own carb guru SOHC DIGGER. I had to do a once over before sending them off to make sure there was no obvious error on my part... WHich I was sure there was.........

I swapped out everything again and noticed the float wasn't springing back... The float itself was bent. Getting caught on the body itself.... I swapped it out with another float and no more leaking....

I did a 10 min shake down and no leaks/over flows at all.........

I think it is fixed.