Removing carbs?

Yes, exactly.

 

I would suggest that you do a thorough cleaning of the carbs, making sure you have cleaned the enrichment circuit and its passages in that order. Then after reassembly, clunk test, bench sync, and then wet set the float levels. Wet setting the floats is very time consuming, but of major importance. You will need either a small aux tank, like off of a mini bike or lawnmower, or a long piece of fuel line to connect to your tank that will be off your bike, and clear tubing to connect to the drains to read your float level. Once I got the first carb wet set, I removed all the bowls and "eyeballed" adjusted the other three floats to match the first one. This got them close. Then I continued on the process of wet setting the other three carbs. Very minor adjustment in the float tang makes a big difference in the wet float level. My suggestion also is to put the original petcock (rebuilt or new) back in the bike. Yamaha had it there for a reason. I'm pretty sure Rick C added a on/off after the OEM petcock as more of a safety measure against the petcock failing. That is possibly why Len thought it was a good idea...I dunnno...

 

Not quite true.

That's why there are FLOAT VALVES. If the float valves are operating properly; ie: controlling fuel flow by shutting it off when the proper level is reached, then which style of petcock is supplying the fuel matters not. Nor does the rate of flow.

If your floats are working correctly, you could leave the on/off petcock ON and nothing bad would happen. Just like you could leave the vac-op unit on PRI and nothing should happen.

It's the float valves that shut off fuel flow into the carbs once the bowls are full. Period.

The on/off petcock is considered an "upgrade" because it forever eliminates the vacuum-operated part of the system. No need to rebuild, no diaphragm to get a hole in, etc. Just a simple faucet.

Some of us consider the vac-op unit to be an "upgrade" over the manual type.

 

Then why when ever some one chimes in about gas in the oil all the experts here (and you know who you are) always say to check to see if the petcock is on prime. I have personally flooded my crank case while on prime and my floats is set dead on , using the wet set method and brand new float valves and seat. Don't leave it on prime it does not overflow.

 

The enrichment tube is on the float bowl side right? That small brass pipe that sticks out? If so, those things were spotless, guitar string went right through.

 

I have added an on/off switch onthe gas line between the vaccum operated petrooster and the carbs to make sure than no gas goes any further when the bike is not running. Once I have time to rebuild the petrooster to be sure that no gas overflows the carbs I will grt rid of it.

Sometimes you do not get the wrong answer, you mY be asking the wrong question little grasshopper.
Oogway: The universe has brought us the Dragon Warrior!

 

The reason that we suggest the PRI, is because:

Much of the time there may be a leaky fuel needle or more, often due to a bad float, BUT the petcock is in fine working order. SO.......when it is on RUN or RES, the only gas that goes through is when the engine is running, and when it is off, the gas simply doesn't flow to the leaky float or fuel needle.. However, when the the petCOCK is set to PRI, the fuel flows at all times.......now there is nothing stopping the fuel, it runs through the leaky fuel needle, continues to fill up the carb bowl, it overflows, runs into the cylinder, seeps down past the rings, fills the crankcase, backs up through the vent tube into the airbox, fills the bottom of the airbox, saturates the airfilter, runs out the drain holes in the airbox, ruins your clearcoat on the engine, and then either overheats and explodes, or just goes right to blowing up when you press the Start button and it violently backfires.........and blows up.

Now, that all being said, much of the time when we suggest checking to see if the petcock was left on PRI, we also say: If you did, then you have a bad float or needle valve. If it wasn't, then you have at least a leaky petcock, and also some float or fuel needle leaks, too.

As far as bad floats themselves, If you want to get an idea of what a bad float looks like-----they are either cracked, or even split right open and often shrivelled up sort of like a rectangular-ish prune. When a float cracks open, the gas gets inside, does funky things to the innards, and now the float doesn't 'float'. It sinks. When it sinks, it pulls the fuel needle down, and fuel constantly runs into the bowl, which will fill up the carb to overflowing.......... etc........ etc....... etc............... BOOM.


Finally, just because these mentioned items can leak, doesn't mean you are automatically going to blow up. It can happen though. Most often, not.

SOMETIMES, a little speck of dirt can temporarily make a fuel needle stick open. My 700 is a case in point...........I had been riding it two years, and one day went out to fire it up and found a puddle of gas/oil on the floor. The crankcase was full of gas/oil, etc............. petcock was on ON. So, I drained and replaced the oil, filter, etc..., put an inline switch on the fuel line. Occasionally I will forget to turn the switch off. However, I've never had that happen again. Probably some dirt moved on through.

Dave F

 

.009 or .010 high E string

 

kleraudio, I have doubts about how u said the enrichment tubes were clean. Most guys say they poked for 10 min. And finally got it. I'm not saying yours arn't open but do u know there's a tiny jet at the bottom of that brass pipe? Can u spray carb cleaner thru it with the little red tube on the can from the bowl out the top of the pipe or down and thru it and in your face like everyone else does. U made it sound too easy.

 

Enrichment tube, you mean the the tiny brass tube that sticks up through your float bowl? If that's what you're talking about then yes, I stuck a piece of brass bristle brush right down in there with no problems.... where does the other side connect? It's not that pluger because when I pulled those (which were also very clean to begin with) it doesn't lead down into the floats, it's stopped, I'm still not exactly sure what that plunger does exacty but I cleaned em anyways!

 

How to clean the enrichment circuit: http://www.xjbikes.com/Forums/viewtopic/t=8918/highlight=clean+enrichment+circuit.html

 

Flush the "Enrichment Siphon Tube"

Fill a Bubble Syringe with Carb Cleaner.
Fit Nozzle right over the Tube.

Alternatively:

Shrink-wrap attached to Carb Cleaner Red Tube.
(Only shrink the wrap to the red tube, ... leave the end open too slip-over the Siphon.

 

Working now and am on phone. I saw the link and tried it. Stuck red tube in hole and sprayed. Fountain of youth. At least 10 feet of spray!

Here's the thing. Bike doesn't start when I push the button. I have to throttle it to et her to start??? Everything in these carbs is super clean. Someone has been in here. I spent 2 days breaking it down and doing ricks manual to the letter. So why didn't my bike start when I pushed the button?

I don't feel like I wasted my time though because now I know how to clean carbs!

There's still the gas in the oil thing. I smelled it today and it's only very faint. I'm wondering if it's residual from gas in there before? Maybe the po got the carbs cleaned before selling? This puppy is CLEAN. was very clean before I even got to it.

 

And also, the drain screws are completely stripped. Not by me. Any ideas how to get these out so I can wet set?

Lastly, shouldn't 1 and 2 drain screws be facing riders left and 3 and 4 facing riders right? If so I'm the exact opposite right now.... Can you mix and march float bowls?

 

Heat and/or impact screwdriver. Worst case scenario, you might have to either dremel a slot in the head, or use a screw extractor, but this last one is tricky.

Replace them with drain screws from Chacal. Drain screws are special, can't get them at hardware stores.

You should be able to switch them right way round.

 

I have none of those things listed I feel like the impact screwdriver won't work as that's a JIS screw and anything with force will strip it further? Am I way off there? I also don't have a dremel, do they make cutting wheels that small? If I go in there with a cutting wheel, I'll end up ruining the outside of the float bowl, as that's a set screw?

That leaves extractor, I can get a set from home depot for around 10 bucks, why is that a tricky situation?

And yea, I'll need to move around some float bowls, I wonder why the PO did that?

 

Once you pound the driver in it doesn't really matter. If the screws are stripped they are no good anyway.

They don't. You take a regular wheel and grind a rock or something with it to make it smaller. You can also do it with a burr. If you cut the sides of the hole a little, it will look ugly, but will not affect function - the sealing part is deep inside.

Because if you break an extractor off in the screw you will be well and truly screwed (pardon the pun). They are hardened steel and very difficult to drill through.

 

Mine were stuck bad, before trying an extractor or grinder, buy your self the cheapest propane torch from a hardware store..around 10 to 12 bucks...take the float bowls off the bike and the carbs and wash with soap and water to remove all gas residue. Have some rags or heavy leather gloves ready, Place a few drops of olive oil into the drain screw (which should be facing up) and heat the bowl around on the housing around the drain screw from the outside of the bowl until the oil bubbles, smokes and seems to disappear. It doesn't evaporate, it has penetrated between the screw and the housing. With a lot of downward pressure on a screwdriver, try to remove the screw slowly. Some of the drain screws may require multiple treatments to finally release. Also, without wet setting the floats, will create starting and running problems, as well as gas overflowing into the crankcase. Hope this helps...

 

Screw the bowl to a block of wood, so you can get some real pressure on it.
Then do what Bruce said.

 

Yes, bowl drain screws #1 & #2 should be facing out to the left & #3 & #4 should be facing out to the right when sitting on the bike....

 

OK, I'll have to find a torch and a piece of wood... so just hitting them with PB blaster and letting em sit wont do much aye? That I have handy...

Even so, the threads are almost one on these screws (probably why whoever cleaned it didn't bother to set the floats) not sure if heating them will loosen them so much that I won't need much "grab" on screwdriver to screw connection. i'll see if my buddy has a torch first.

EDIT: a hardware store really won't have replacement screws for these? I for sure have to mail order them?

 

Chacal.....has allen head float bowl screws.....defintiely buy them....makes for next time much easier.....see pic

 

http://www.xjbikes.com/Forums/viewtopic/t=4281.html

 

Milliken,

I'd rather have a screw extractor set than a torch, I know I'd use that more than a torch. but I've been told by a few people NOT to go the extractor route.... I plan on buying something over the weekend to do this, but not sure what....

 

I just thought of something, I have a pretty good cigar lighter that runs on butane and has a triple flame, you think that would work??

 

you need a bigger flame than that......buy a propane torch at Home Depot or Lowes.....

 

Will do. How much flame should I be applying to the outside of the screw on the float bowl? I don't want to discolor it, or worse, melt it...

 

You want to gently warm the BOWL around the screw, not specifically heat up the screw itself.

You won't melt anything.

 

The screw is steel and the bowl is aluminium. The alum will heat faster that the steel. Hopefully the expansion between the two metals allows the olive oil to seep in and believe it or not, cook the corrosion between the screw and the bowl allowing the screw to be backed out. If you apply force and it isn't giving, more oil and reheat. I had one bowl I worked on for about an hour reheating it at least a dozen times before it came out. You have to have patience and take your time and don't over force anything. And Polock, sure wish I would of thought of screwing the bowl to a board...jeez...

 

Yes. They have special tapered tips that seal.

Theoretically you could make them out of regular screws, but considering that we are discussing using a lighter for a torch, I doubt you have the equipment for that.