Help with my floats

[Stone Hands]

Hope someone can help me out. I seem to be brain dead on this. I have restored a 1972 xs2. Was running great until I was sucking up rust. I pulled tank and cleaned and coated. Came out perfect. I pulled the carbs and soaked them, replaced on of the diaphragms that had a hole, new fuel lines, blowed out all passages and reassembled. I have good spark but will not start. Acts like it is flooding out. Fouling out the new plug after a few attempts.

I may have the floats in upside down or out of adjustment. How do you know which way is correct to put the floats back in. When I took them out to check for leaks while cleaning the carbs, I thought I had them back in correctly.

If not that, then what else might be causing my baby to flood out. Help. It wants to start and has burped a few times. Seems to want to start after I drained the fuel out of the bowls and then tried to start it.

 

[5twins]

I think they'll only fit in one way. They hang too low to get the bowl on if you put them in upside down. Here's how they should look .....

The floats are pretty delicate. If you manhandled them removing and installing them, you may have thrown the adjustment off.

 

[ANLAF]

Stone Hands, I agree with 5twins (and he's the wise man of carbs) - those floats are delicate creatures. I spent a while a couple of weeks ago adjusting mine again, and it takes patience and care with them.

There is one thing you might consider - if you are setting them to the correct height but you are still getting flooding, there might be some wear (and these bikes are 30 years old remember) on the delicate parts like the pin the float tang sits on. It only takes a small amount of wear to make a difference. You might consider compensating - for example my BS38s should be set at 24mm but with trial and error I have settled on nearly 26 mm - that's 1mm allowing for wear and 1mm to allow for my weak eyes when trying to see those tiny lines on the ruler. It doesn't sound too scientific, but it really is a matter of getting to know those carbs by making adjustments until you hit on the setting that works the best for your bike.

One more thing, is the flooding on both carbs, or more noticable on one?

Anlaf

 

[ANLAF]

Stone Hands, I mis-read your post - you only say it feels like flooding and it will not start.

OK, let's start again:
Spark - check, so what do the spark plugs tell you (colour, etc).
While the plugs are out, can you see the valves moving properly in both cylinders?
Check there is nothing blocking the exhaust system.
You've got a spark so let's by-pass ignition checks for the moment - back to the carbs: 5twins and the other guys are far more knowledgeable than me, but I have dismantled mine a few times now, and one of the things I learnt was not to mess with the synch screw - see my video (another something 5twins helped me with).

Anlaf

 

[ANLAF]

Stone Hands

Have you got an in-line fuel filter on there?

Anlaf

 

[wherearewe]

Setting float height can be fiddly, esp if your eyes are a bit shit (like mine). Some people make a template tool for float height with an old credit card or something. Kinda make a tee or upside down "L' shape to the spec height. Then you can slide that along the carb surface over the top of the floats to see if it is pushing them down/perfect/not touching at all. Adjust your float tang accordingly so the height is correct. Do so without the bowl gasket on and check both sides as the floats can be bent. Thats pretty much it.

 

[ANLAF]

Wherearewe, I like the credit card idea. My eyes are bad, too, so any help there is good.

Anlaf

 

[Stone Hands]

Thank you very much. I have been careful with them. My pin came out very easy and did not have to use ANY force on any part of the float bowl and its inner workings. Thank you for the pic. Great help.

 

[Stone Hands]

Seem to more in one side then the other. Here is a part I did not mention but should have. I had purchased a new diaphragm for one of the carb slides. Not a new slide. When I put the new rubber one on it does not have the little notch that the originals had so you had the slide aligned up correctly. I had the slide facing the wrong direction. I repositioned it correctly and put back together. When I took the top of the carb off it was wet with fuel. Now neither seem to be leaking. I also am not getting any running out of the overflow lines on the floor either. I think I will adjust the floats as up to this point I have not. I have just made sure that I had it all together correctly. thank you anlaf

 

[Stone Hands]

Thank you very much. Up to this point I have not touched any settings such as fuel, rich/lean settings or idle speed. Bike was running good. I only took off tank, cleaned everything, soaked carbs and blew our all passages. New diaphram on one carb, and put all together. No other changes. I can set everything else once I get the girl running. It wants to start. has chugged a few times before flooding out. It is not starved for fuel. for what that is worth. Thank you Anlaf

 

[Stone Hands]

Yep I do. Always have had one. However you bring up a good point that I did not check. I am using old inline filters that I took off. I am getting plenty of flow so I did not think about that. I will probably swap them out for new just to take something off the list. Thanks for the heads up.

 

[Stone Hands]

That will be my next plan. I will let you know what is the result. Thank you.

 

[Stone Hands]

Thank you everybody on the thread. I have not made any physical adjustments to the float up till this point as I did not think I had changed or moved anything. I was that careful. I will however get my carbs off and be sure that I set them correctly. Thank you again everyone for jumping in. I have gotten some coughs, gasps and about 3 or 4 seconds of running or chugging. I am sure it is fuel, and it is in the floats. Clean tank, new fuel lines, new petcocks from mikes and getting plenty of flow. I am getting good spark as I pulled the plugs and checked it while using the elect start. Will post back my results.

 

[ANLAF]

Let us know how you get on.

I have just posted Part 10 of my rebuild video - the first ride. Ignition timing is off but that's what a 79 sounds like set up 27.5 pilots, 135 mains and second notch on float needle, pods, and through exhausts.

Anlaf

 

[wherearewe]

Stonehands: Have you seen the quote reply? Just to the right of the quick reply button. It allows you to respond to specific post. Might make it easier to follow the thread.

 

[Stone Hands]

Stonehands: Have you seen the quote reply? Just to the right of the quick reply button. It allows you to respond to specific post. Might make it easier to follow the thread.

Did not notice them before. Thanks for the tip. Easier is better. Thank you.

 

[Stone Hands]

Let us know how you get on.

I have just posted Part 10 of my rebuild video - the first ride. Ignition timing is off but that's what a 79 sounds like set up 27.5 pilots, 135 mains and second notch on float needle, pods, and through exhausts.

Anlaf

ANLAF. A question for you. I found what I thought was the problem. The left side carb, as you are sitting on the bike, had a leaky float. I took the carb off and shook the float and sure as heck it had fuel in it. I found small cracks on the float. I had a gas proof, clear cement that I put on the area and let set for 24 hours. The cement cures in 6 hours. Put it all together and it sputtered and tried to run shortly.

The question is this. When I took the carb off and took off the top, the rubber diaphragm had fuel on TOP of the rubber boot. Not allot but enough where you could see that fuel had somehow gotten on top of the rubber boot. What would cause that??? I did not think fuel could get to that side of the boot.

 

[Stone Hands]

Let us know how you get on.

I have just posted Part 10 of my rebuild video - the first ride. Ignition timing is off but that's what a 79 sounds like set up 27.5 pilots, 135 mains and second notch on float needle, pods, and through exhausts.

Anlaf

ANLAF. A question for you. I found what I thought was the problem. The left side carb, as you are sitting on the bike, had a leaky float. I took the carb off and shook the float and sure as heck it had fuel in it. I found small cracks on the float. I had a gas proof, clear cement that I put on the area and let set for 24 hours. The cement cures in 6 hours. Put it all together and it sputtered and tried to run shortly.

The question is this. When I took the carb off and took off the top, the rubber diaphragm had fuel on TOP of the rubber boot. Not allot but enough where you could see that fuel had somehow gotten on top of the rubber boot. What would cause that??? I did not think fuel could get to that side of the boot.

 

[ANLAF]

Stone Hands, you might be lucky and have had a freak appearance of fuel, or it is a failed diaphragm. The Carb Guide tells you how to test the integrity of your diaphragms. I have carried out the test after I found a small pool of fuel on my left carb diaphram. It goes something like this:

With the carbs reassembled (caps secured with springs in, and diapragms properly seated hold the carbs upright. At the intake side you will see a sausage-shaped hole on the upper part of the intake. With a clean finger raise the slide (careful not to bend the jet needle). When the slide is raised hold it there, and with another finger or thumb cover the sausage-shaped hole - hold it there and release the slide. If the diaphragm is working it should fall slowly into place, if damaged it will fall rapidly. Do the test on both sides.

Also, it says in the Carb Guide to hold the diaphragms to the light for a visual check for holes, etc.

Fingers crossed your diaphragms are working.

Anlaf

 

[ANLAF]

By the way, Stone Hands, take great care removing diaphragms, and handle gently.

Anlaf