I need an express expert.

Okay everyone on here has been alot of help and I have learned so much about maintanence/repair. But I am stumped on this one and I need someone who knows their carburators. Can you solve the riddle?

My 77 express, ran and then ran bad and then didn't. I cleaned up the carburator but didn't get it to seal properly due to gasket/hardware issues, and then after that I was having trouble getting the float needle just right. I bought some new stuff and got it all put together and now it starts immediately. (keeping in mind the gas drain valve is all the way shut). The thing is leaking gas like crazy. It started quicker then I have ever seen but it is literally spewing gas, like if I let it it would drain a gallon in five minutes. All the gas is coming out of the release hose on the bottom of the carb.

help me and i will crown you king of maintanence and repair. (please I'm desperate, im sure you all know what a downer it is to work on a moped and have it still not run properly).

Re: I need an express expert.

Leon Swarmer /

Surely you have closed the screw where the drain hose is connected?

Re: I need an express expert.

The screw that goes into the carb bowl. Is there a o-ring on the screw? a damaged o-ring? And the seal that the carb bowl seats on when you attach the carb together? is it there/damaged? I ran into the same problem u are with my 2 exresses.

Best of luck,

Chris.

See attached. sry i could not use a different colour. the program wouldn't let me use any colour but black.

1159846513_h01140019.gif

Re: I need an express expert.

You might want to zoom in on the pic. sorry.

dhemi1.

Re: I need an express expert.

if the float is not properly lifting the needle, or the needle is not seating properly, or it is damaged you will have a river of gas flowing. or it couls just be that o ring. If it stops leaking while the motor is running its not the o ring. shut off the petcock for now

Re: I need an express expert.

I'll second this. I have an Express and I can say it sounds like your float no longer floats or the float needle is toast. Pull the carb apart and check those two things. While you're in there, back the drain screw out to check for damage.

By the way, get used to taking the Express carb apart all the time, they need what seems like constant maintainence.

Re: I need an express expert.

the solution to constant maintenance is a $3 briggs and stratton inline fuel filter - priceless

Re: I need an express expert.

And that can be purchased at Wal Mart? Ace Hardware?

And the fuel filter is postitioned between the Petcock and the Carb yeah?

Re: I need an express expert.

Oh and as far as the float, I've got a similar model carb with some interchangable parts, there is a different float (plastic instead of rubber) I haven't used it because when I put it in there is about and eighth of an inch of play, where as with my old black rubber one there is about an inch. Which is right, how much should a float be able to move. And how hard can it really be to seat the float needle, it seems like its either in or its not and I don't see any obstructing grime.

I am sure you know putting the needle in the float in can fry your nerves on account of their size and the delicacy of the process. I feel like I am doing a double bypass on a mouse heart.

Re: I need an express expert.

Your problem can be unrelated to the float.

I've seen often where folks turn the bowl screw in too far and split the housing behind the screw.

These bowls are made of very crappy metal. When you put the scooter to bed for the winter, you are supposed to turn off the petcock and drain the carb by opening the bowl screw. Once it stops dripping you turn it back in.

Some folks make it too tight and split where it seats.

If this is the case the gas will run out and the bowl will never get enough gas in it to lift the float.

Just like a running toilet !!!

Take the bottom off the carb and fill it with gas. If it comes out, that's the case.

What you think is happening is overflow. This is when the needle valve won't close. You can test this by blowing through the fuel inlet and move the bowl up and down to cut it off.

It only takes the pressure of the float rising on top of the gas to shut it off.

Make sense?

Mike

Re: I need an express expert.

It makes most sense, but doesn't the float go up when full, thereby releasing the gas through the needle valve? This might not be paramount to me fixing the leak but shows that there are a few fundamentals to the carb's functions I do not understand (i think i got throttle, choke, idle, and mixture figured out at least).

Oh and ps, it its just a busted screw on my drain valve should I just rig it with something removable so that its plugged all the time until I need to drain the carb? Or is that dangerous?

Re: I need an express expert.

RTV? epoxy? not sure.

ace or walmart or northern for the fuel filter, yes between petock and carb.

Re: I need an express expert.

Just plug up your drain hole with JB Weld. I had to do it to mine because the drain screw was lost. Works great, no leaks.

Re: I need an express expert.

Leon Swarmer /

go with the 1/8th inch

Re: I need an express expert.

Try as much as possible to stay stock.

Also do not plug the drain tubing. Gas will come out for overflow issues (this protects your motor from getting a crank full of raw gas) as well as because the screw is hurt.

Be your best judge of how to resolve this but always try to use less permanent solutions if you feel you may want to go back to stock by some means.

Again, make sure you understand or ask.

Good Luck,

Mike

Re: I need an express expert.

So if the drain valve is shut all the way, should I still be able to blow air through it? I noticed that I can when I was cleaning my carb (it tastes so good to put your mouth on bike parts).

Re: I need an express expert.

Leon Swarmer /

If your drain is shut you should not be able to blow through your darin valve, if that is what you are asking.

if however you are blowing into the carb fuel inlet with the drain valve shut, yes you should still be able to do that.

I have a bit of fuel line that has never had fuel in it that I use for testing. It justs tastes like plastic.

Leon

Re: I need an express expert.

I seen the cracked float bowl as well, I fixed mine well enough to last through summer with some 200 grit sand paper and some JB weld.

Re: I need an express expert.

Test it the way I told you.

Take the bowl off of the carb, fill it with gas and see if it comes out of the drain tube when the screw is closed.

When the carb is together and you blow through the drain tube you will be able to.

Like I said the drain sources from two places.

1. From ther drain screw in its open state.

2. From the overflow tube that is sticking up from the bowl like a snorkle.

Again, if it's because of overflow, it's most likely the float valve not closing.

If it's the drain it's because it's not seating well.

You need to understand this then figure out which is which the way I described in an earlier post in this chain.

Mike

Re: I need an express expert.

I usually take the carb all apart and shoot compressed air through the main jet, and sometimes some crap will fly out that has been clogging things up. If you have the little rubber nipple on the top of the needle, and its not crappy looking you should be ok. If you install the needle and the float and put the screw on, take that part of the carb and flip it upside down so that you are looking at the float on the top. The float should be parallel to the surface of the carb, if its not you need to bend the tang on the float so that it sits level. There is a specific height for the float but its easier just to eyeball it than to measure since they are about the same.

does your petcock work? usually on my bikes i run the motor for like 30 seconds when the petcock is switched off so that the carb is not over flowing and then the needle will seat pretty well when the float drops.

Re: I need an express expert.

lost highway /

Okay this is wild. Last night I went to work on the carb knowing that the needle wasnt sitting right. I checked and my float bowl doesn't leak until you open up the screw (good advice). Put it together, started in five seconds ran great, etc. etc. This morning my lady and I went to go on a ride (shes got an 83 express) and it was leaking gas like crazy. Somehow the float got stuck, or something. So I tried something weird, I bent the little metal part of the float attatchment that the needle hangs off to make a tighter fit on the needle valve. It stopped leaking gas, but I think the needles in too tight, it wont start. Heres where it gets really complicated:

I opened the drain valve just to see if there was any gas in the bowl; there was. So is the tighter seated needle still preventing it from starting even though gas is obviously making it in the float chamber? Or does that all check out as functional and I just need to clean it for the twentieth time and make sure the gasket in the carb is set in right for proper pressure?

Re: I need an express expert.

what is your airbox situation right now? Try taking it totally off. see how it starts then.

have you installed an inline fuel filter yet?

Re: I need an express expert.

Well I have a generic air filter, historically it has started okay with it. Fuel filter has not been tried yet, I was waiting to sort the carb out first. Do you think it could straghten this out? I feel like the float needle system on Hondas was manufactured in the firey pits of hell.

Re: I need an express expert.

dude without the inline filter your carb will constantly clog and you will need to clean it every 5 miles. If you can get it to keep clean then you can fine tune it, but for now it seems like its not staying clean enough to be consistent. When they do get junk in them, they drain out the bottom like yours was doing.

Re: I need an express expert.

What you're saying makes perfect sense. Well this weekend: inline fuel filter, reduce the tightness added to float needle ever so slightly/pray to some unknown two stroke late seventies motor bike god.

Re: I need an express expert.

Exactly. Clean the carb too and install everything, then you will be able to eliminate any confusion due to clogs. Let us know how it goes. $3 red or white briggs and stratton filter will work just fine, use hose clamps if you arent sure how tight your connections are.

Re: I need an express expert.

which reminds me cause I am already short on those little hose clamps, where can those be purchased? I didn't see any at the auto parts mart.

Re: I need an express expert.

umm, autozone, carquest if they have em near you. Any auto specific place should, Napa, checker, places like that. They have fuel line too, its like 25 cents for as much as you need (if you need any). Sometimes they keep these things behind the counter, so just ask for it. if you tell them what kinda fuel hose you are using they will know that you need the smaller clamps.

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