XS1100H Carb's

[Athedra]

I got my XS as a present and in a non-running condition. Carbs was all messed up and electrics was chaos.

I purchased a second hand set of Carbs, cleaned them, fitted new carb kits, did what needs to be done, and she is now a running machine again.

Since then I have a constant leaking second carb. I have removed the carbs probably about a hundred times and cleaned it, reset the float, refit, and the next day I have petrol all over. The carb is leaking through my filter (Cone filter), and even blocked off the primary flow pipe that bypasses the needle and seat. My fuel valves are not working, so shutting down the fuel line is not an option. (The valves is on my to do list)

Any advice would be appreciated. This is the only thing still wrong with her, and a problem that is busy getting me under.

[xs11head]

Did you replace the needle and seat? Even if the float height is correct, if there is any leakage at the needle/seat it will overflow. If you don't have a replacement set, remove the seat and clean it with brasso and a q tip and make sure there is no dirt anywhere near the needle.

[xs11head]

Also, vise grips clamped on the fuel line make a great petcock

[tinman905]

Make sure the bowl gasket isn't catching the side of the floats .

I had that happen on a new rebuild kit. Work the float up and down to see if there is any interference with the bowl gasket.

James

[jjwaller]

One thing about these carbs I've noticed, is that when first filling them,
they will initially leak through the float valves. (and possibly never stop) So if your petcocks don't shut off at all, then they will likely leak.
I have finally replaced the vacuum petcocks with the manual ones
from Mikes XS. God do I love them.
So if you can, fill them and stop the fuel and let them sit for a few seconds.
Then start adding more fuel. They might work this way. BUT, Fix your petcocks!!

[Athedra]

Great advice from all of you. Wil pull the carbs tomorrow during lunchtime and check the carb. I even swopped carb one and carb two's needle and seat to see if it might be a dodgy needle and seat, but leak stayed on carb two. Will look at the gasket tomorrow, and yep do have the old vicegrips on at night.

I am in SOuth AFrica, Bike Hospital cant help me with petcock's, and BD racing's reply to my request was: " You are aware that your bike is nearly 30 years old?"..... Any other newer models petcocks I can use there (with same spec's?, or would it be better to add in an additional Vacuum valve system? Somone (on a similar site) suggested that my float bowl might be cracked and is sucking air through there resulting in the push-up of the fuel in the float bowl into my carb. Is this a possibility? Doesn't sound right, but heck I'm no carb mechanic.

[xs11head]

That is so bizarre about the carbs. I took mine off to check the jets and a light cleaning and when I put fuel to them they leaked. I just kept cutting the fuel to them and they finally stopped leaking. In looking at the floats they appear to be designed a little "off center" with the way they attach.

[skids]

Also, vise grips clamped on the fuel line make a great petcock

WHAT?

[skids]

No. Not possible, or at least it shouldn't be. Our carbs are vented to atmosphere to prevent such a vacuum from occurring. If the vent is plugged, it can cause carbs to overfill while the engine is running.

Somone (on a similar site) suggested that my float bowl might be cracked and is sucking air through there resulting in the push-up of the fuel in the float bowl into my carb. Is this a possibility? Doesn't sound right, but heck I'm no carb mechanic.

[xs11head]

OK,vise grips make a good temporary petcock, if your vacuum ones are leaking fuel to the floor. Don't get sooo technical.

[xs11head]

And it is possible, here are 2 instances where the carbs are clean and the floats were properly set. I have worked on alot of carbs on various bikes and have never seen this happen.

[DGXSER]

Possible that a cracked fuel bowl will cause overflowing of gas into the bike, when the bike is off??? Ummm...not unless physics has taken a hiatis in your neck of the woods.

Sorry, but that is a no-go in my mind. A cracked fuel bowl wil result in fuel flowing out onto the floor or onto your starter, not overflowing the bowl. Since the bowl is vented to atmosphere, the carb/engine is NOT going to pull air through the fuel in the bowl before it gets it from the vent.

Granted I have not been working on these beast NEAR as long as alot of the folks on here, but I have had my hands knee deep into alot of carbs in the last year or so. Every one of them that had gas running out the air box or into the engine had a problem with the float needle valve(s). That valve seal area is so small it does not take much to cause a gap that gas will flow through. I had brand new viton seal valves and new seats on my bike and had ALL kind sof trouble with leaking gas. Two things were the cause, the float sticking on the gasket which I trimmed, and my auto type fuel lines were chaffing against the babrs of the fuel Ts when I put the radiator type clamps on. that little bit of chaffed rubber was sticking the valve(s).

[Crazcnuk]

Just buy the petcock rebuild kit, install it and be done with it.

The problem is the float needle is not shutting off the fuel. Either the needle is damaged, or the seat is, or there is crap in there, or the float itself is hanging up. It's fairly easy to test off the bike, so by the 3rd time you should have been testing it before installation!

[DGXSER]

Canuk,

I do advocate the bench test before mounting the carbs. I follow Proms method of testing them before the bowls go back on, then upright after the bowls are on.

However, in my personal experience, you can test them till your blue in the face, everything come up perfectly, and yet you still get a leaker when installed. This happened to me several times in a row until I figured out it was the rubber from the automotive style fuel lines I was using chaffing small pieces of rubber off into the carbs and that would get to the float needle and hold it open.

[Athedra]

Dropped te Carbs today, checked the gaskets and everything was perfect. Tested the needle and seat with air and fuel, and the close of perfectly.

I have noticed that I am only leaking on Carb 2 when on side stand. What strikes me as odd is that I used the "credit card trick" on all four carbs, and it is just carb 2 giving me the head ache. Me ad the wife puts it on main stand now every time we get back home. I haven't found the one man trick of placing it on the main stand by myself yet, but working on it. Apparently something to do with your knee and right hand ........

Does anyone know the exact measurements for the float?. Thinking I might be slightly out on it. I got my measurements from a Workshop manual for the XS1100G, assumed they would be the same, but might be wrong on it.

I opened up my petcocks when I got home tonight. Not much that can go wrong in it, but they are not working the way they should. Kits her in South Africa is non-existant. I spoke to a guy working for Jonway Scooters, and am going to use the scooters Vacuum fuel pumps on my bike until I can trace down a set of working petcocks for her.