Wet setting the float levels

Yesterday I levelled my carbs on my Workmate and started the wet setting procedure. Immediately I noticed a steady fuel leak from there:



Chacal and Hogfiddles confirmed that my fuel rail o-rings are leaking and that I will have to break the rack to replace them. I have to say that I was a bit upset, given the fact that they weren't leaking at all last fall when I took the carbs off of the bike.

So today I was ready to order the parts I need, but I returned to the shed on re-opened the fuel valve and surprise! the fuel rails don't leak anymore ! It appears that the o-rings swelled back at their original dimension and make the seal.

IS this common ?

Anyhow it made me able to do the first step of the wet setting procedure. I found that #4 carb is way too high, actually it is less than 1 mm below the reference line, instead of 5 mm. Carb #3 is at 2.5 mm, better but not in specs. Carbs #1 and #2 are spot on 5 mm or very close. So , tell me if I'am right: with the carbs upside down, I will have to bend the tang up a bit to improve the situation of the carb float #3 ad #4, right?

What kind od adjustment should I be looking for? Will I drop the fuel level 5 mm down if I bend the tang 1 mm up?

 

think about it like this.
if the floats are too high the tang it too far away from the needle and visa versa
that way upside down or right side up doesn't matter

 

So I have to bend the tang towards the float needle to lower the float level, right? Does a 1 mm difference on the tang makes a huge difference on the fuel level?

 

Yes it does. You want to just barely bump the tang each time you go to adjust it.

 

So it is like a trial-and-error procedure, nobody can tell by how much I should bend the tang to lower the level 5 mm?

 

if a guy was really good with geometry he could figure it out but the poke and hope guy would be done by then.
while you're doing this, don't scratch the area of the tang that slides on the needle pin. a divot there could cause the pin to hang up

 

Thanks for the tip. I may give geometry a try before I go to bed.

 

he has the rule under the carb to do it

 

I went back to the shed this morning and noticed a small fuel puddle on the floor under my carbs. I forgot to shut the fuel valve of my temporary fuel supply and carb #4 has flooded during the night and was dripping by the overflow. So there is more than an adjustment to be done on this one I guess. All float seats were very clean, and I put a fuel filter on my setup.

When carb bowls were off, I noticed #4 carb float needle spring was operating like the others but looked noticeably weaker than the other ones when I performed what I'd call a bouncing test. Could it cause the carb to flood?

I'll swap needles with carb #1 and see what happens.

 

Lift the float manually make sure it's shutting off. Sometimes a rap with the handle of a screwdriver will stop the flooding, of course, when the motor is running the vibration does that anyhow.

 

I'll give it a try. If the flaot seems to shut normally I'll try swapping with #1 carb.

 

The float operated very smoothly when pushed up manually so I drained and removed the bowls and measured the float height with the carbs upside down. All carbs #1, #2 and #3 are around 19.2 mm but #4 stands at 17.7 mm, which is a BIG difference. All tangs seem to be equally bent but I,ll try to measure the space accurately with my valve clearance gauges, at least on carbs #1 and #4 that area bit more easily accessible.

 

yes spring can be a prolem, do you have rubber tipped valves?

 

No, metal tips.

 

Well I think I got the picture: carbs #1 and #2 tang "openings" are about the same around 0.013 inch. Tang #3 is around 0.016 inch and #4 is around 0.019 inch !!

What it says to me is that even if the tang is more bent on #4 float, it is not enough to push the needle up to shut the fuel supply. It also suggests that someone has already tried in the past to compensate the weak needle spring by prying the tang more opened., but it doesn't work anymore.

I think it's time to order a new needle. The question is: should I order a new seat to fit the new needle?

 

you should really get the needle and seat as a set

 

I would order a complete set of needles and seats. Chacal convinced me to use the solid brass needles and I've had zero problems with them. Also, I use a very small screwdriver to adjust the tang. I found needle nose pliers hard to deal with, especially when making the final adjustments.

 

Solid brass needles is what I already have. Three of them work properly , so I don't see any reason to buy 4 needles and 4 seats for the moment.

 

did you clean up the seats at all? i take a bit of #0000 steel wool on the end of a q-tip and spin that around in there till it's nice and shiney in there, then a drop of chrome cleaner on a fresh q-tip and spin that a minute, now clean it up and drop the needle in there and give it a spin or two and you should see a line on both pieces where they seated. now they shouldn't leak

 

Yes, but differently: I put the bottom part of a wooden golf tee in my drill , squeeze a bit of Aerosol (chrome cleaner) on the tip pf the tee and spin it in the float valve seat for a few seconds.

The little spring in this needle is really weaker than the other ones. With the carbs upside down and bowls removed, if I give a little tap on it, the float in the other carbs bounces more than four times, but only twice with this one. The measuremetns I took of the height says a lot too: even with the tang bent the most, the float stands a lot lower.

Maybe a could try bending the tang even more and see if I can make it close or not.

 

i think the golf tee is the Rick-o-matic method, i don't play golf. i have seen those little pins get gummed up. i thought that the tang pushing on the pin was slowing the flow down and when the pin was all the way in, the tang hits the needle and stops the flow altogether. i doubt the pressure of that tiny spring could seal the needle/seat.
definitely bend the tang to make the gas level right.
i've seen more carbs without the little spring pins than with them

 

I assumed that the springs were to absorb the bumps and help keep the needle and seat from wearing too fast. That said, a bad or weak spring would alter the float height. I still think replacing the needle and seat, at least for that carb, is a good idea.

 

I bent #4 tang this morning a LOT more than the other ones to reach close to the average float height. I put the bowls back on and connected the fuel supply. The carbs don't leak for the moment, but I know for sure that a slow leak could creep up slowly over hours.

I'll check again tomorrow morning, It it still dry under there, I will try to wet set #3 and #4 again.

 

OK, I got all bowl fuel levels in specs. I bench synced the carbs last fall when I took the carbs off so they are OK too. MIxture screws are set at 2.5 turns. So I thought I was ready to put the carbs back in their boots, I put a bit of oil in the intake boots to help the process.

I've spent more than one hour tring to wiggle them in, with no success, THe best I got was one end in, but as soon as I tried to push the other carbs in , the other end of the rack popped out. VEry frustrating. At a certain point I even use a very long carpenter vise with one end at the headers (with a block of wood) and the other end at the top cross bar of the rack. Almost got it but now I think I'd need two vises to keep the other end in place.

Weather was good, around 70 F so I figured I didn't need to heat the boots with an air dryer, maybe I'm wrong. ANy help will be greatly appreciated.

 

You still need to heat the boots. 70ºF ambient is not warm enough to soften the rubber.

 

We may be right. By the time I had the same thought, it was a bit dark in my shed and I was exhausted, so I quit !

 

Better to quit than to keep trying and mess something up

I know for a fact that 110ºF ambient isn't hot enough to soften the boots much either.

 

i seem to have better luck getting all four lined up with the tubes then push in and wiggle up and down
the clamps have to be off, i use screw clamps

 

I've never had to heat the boots on my XJ700. I do use a light coat of silicone grease and a piece of wood to gently force them in with a wiggle or two. That said, in my opinion getting them back on is the worse part of having to clean them.

 

Agreed.
I also use a piece of wood and found it very helpful to grunt and groan a lot, with a few "for the love of everything holy, why don't you just go on?!" comments thrown in. Although last time I did it it wasn't much over 70F but I had the foresight to make sure it was sitting in direct sunlight a few hours prior to wrastlin' with them.

 

I have to say that I did it twice on my Maxim-X and I found it a lot easier, didn't need an air dryer. The boots of my Seca 900 are a bit stiff.

 

With some grease and some heat on the boots, it took me three minutes to push the carbs right in. Thank you guys !

Now I'd like you to tell me what the tube on top of the fuel supply is for? On the picture , the fuel supply is on the right (it looks grey) the other tube is at its left and looks black. It connects to a T that seems to fit pretty loose in the carb bodies.




I plan to let it stick up during the airboots installation and push it downwards between boots when I'm finished, does it sound right?

 

Last update: I realized two days after I adjusted the tang of the leaky float that it was leaking again.

I replaced the weak-spring needle with a new one this morning, leaving the old seat in there for the moment. It doesn't leak now. Next update in a couple of days, we'll see

 

The other line is for the float bowl vents. It just sits there, not connected to anything else. Let it stick up under the tank. (unless..... do you happen to have a California model? I know that's really unlikely, but....)

Hey, when are you going to put the year and model of XJ in your signature?

 

Done !

 

Also wanted to report that it was 60 F outside when I started to try pulling the carbs out of the intake boots, and I realized quickly that I had to use the airdryer again. My boots are stiffer than they look like.

 

Had no luck with the new needle in the old seat. THe level has slowly crept up for 30 hours and it has reached the point zero. A few hours more and it would leak thru the overflow tube. So I have to put a new seat in there too.

 

LAst update: I installed the new seat-needle combo on carb #4 a few days ago and tested the fuel level several times at my satisfaction. It was stable and in specs. So this morning I put the carbs back in the intake boots (easy when boots are warmed up), slipped the airboots back on the carbs (not easy, luckily I have thin hands, I could push them out of the airbox with my left hand while working in from the outside with the right hand to align the tabs), installed air filter, and battery , with a new vacuum tube, a new 90 degrees fuel filter and a new fuel line. I have to say that the bike hasn't been started for nearly 12 months.

I connected my auxiliary fuel supply (my old lawn tractor fuel tank duck-taped to a ladder) and proceeded to start the bike. It catched at the 3rd attempt and responded properly to "choke" openings varaitions. It idled pretty evenly, so I didn't feel I had to perform a running sync of the carbs for the moment. It let it warm up for a few minutes and when I was satisfied with what I heard I stopped it and put the fuel tank back on and connected both tubes.

I did my best to avoid air bubbles in my fuel line, but I think I still had one because when I hit the road the bike bogged and popped a bit under mild acceleration for the first minutes, just like it did last fall after I messed with the mixture screws, so I was a bit upset at first.

I persisted to ride it 10 minutes more and the bogging-popping totally disappeared. I'll try again tomorrow to make sure this is all gone.

All in all, I'm very glad the Red One is back on the road !

 

You really do need to do this............

 

I know, I just need time to do so !

 

I'd like to know how high the bike is supposed to rev on "full choke" when every thing is right inside the carbs (no passage clogged, no vacuum leak, all selas and o-rings sealing properly, etc)? Does 3000 rpm sound correct ?

 

Around there +\-

 

^ what he said.

 

OK thanks. I wanted to check again how high it revs on "choke" earlier today, but it was too cold , tach wouldn't work until the engine has warmed up. So much for that...

I went for a short ride despite the 40 F , no more bogging nor popping, eveything seemed to be alright, throttle response was pretty crisp. Idle is not as smooth as could be, but considering the only sync I did was the bench sync and the mixture screws are all at 2.5 turns out and that I havn't check the plugs colour, it runs reasonably well.

 

Temperatures are sort of cold these days, between 40 and 50 F, do I have to run a fan in front of the engine during the sync process when it is that cold outside?