[motocross77]

I have a 446 and I just put in a new brass float. Ever since I put it in, gas pours out the top of the carb. I set it to 1/8" and no help. I tried everything!! My old fiber float didn't do this. What could it be? The needle is clean, it has a electric pump. Any help would be great!! thanks

 

[RestMyCase]

Did you change the needle & seat ? Is the new float rubbing on the float chamber body ? What is the pressure output of the pump ? Did the new float come with the small assist spring ?

:thanku:

 

[motocross77]

No, i did not get a new needle or seat. It still looked good so i figured i could still use it. I dont think that it is rubbing but it is so hard to tell. I am not sure what the output pressure is for the pump. It was on there when I got it and I never messed with it. I figured since the old float worked fine with it that the new brass one would as well. The new float did not come with a new assist spring. Thanks!

 

[armstrong]

Well I had the same problem when I installed my new brass float also. If you look at it closely you will see it is very flimsey, I found 1/8'' did not work but 1/4 '' works great. Brass is just too thin as you can see, just use 1/4 '' and you will be fine. Remember they are made in china now.

 

[motocross77]

I changed it to 1/4" but still nothing. Its not shooting out the like a fountain but it is more like coming out that top hole a little. It's slowing coming out. Not alot but some. If I put my finger over the hole it runs fine but when I let go and extra gas goes down the carb it runs terrible. I don't know what to do at this point. I tried everything that I can think of doing.

 

[boomers_influence]

moto
nothing ever stated about the top gasket for the carb.???
new? used?
if it is bad the fuel WILL leak before it it gets to the needle and seat.
good luck. boomer ( the used onan engine parts guy )

 

[boomers_influence]

moto
nothing was ever stated about the top gasket for the carb.???
new? used?
if it is bad the fuel WILL leak into the bowl before it it gets to the needle and seat.
since the viton needle came about,
that leakage is almost unheard of.
good luck. boomer ( the used onan engine parts guy )

 

[motocross77]

Boomer-I used the one that was one there from before. It doesn't look beat up too bad. How would I be able to test to see if that is what is happening? That would make sense because it is not shooting the gas out that hole. It is more like slowly dripping out. I will check it again to see if I see any damage. Thanks guys!

 

[ricohman]

I had the same problem. My tractor would run with the needles closed!
The pump is the problem. You have to much pressure for the float to over come so gas is pouring by the seat.
I solved my problem by rebuilding the factory pump. Works great now.
Or you can get a pump with proper pressure or limit the flow with a regulator.

 

[motocross77]

ricohman-I was thinking thats what is happening. I am going to try and see if I can even find my factory pump and maybe stick it back on. If not I will probably get a new pump and see if it helps. I am going to hook up a gravity feed tank tomorrow and that will tell me if it is the pump or not.

 

[boomers_influence]

moto
if your carb has the brass float,
it should be the DD carb.
when used on case, the fuel pump is part of the carb.
can you post some pics.??
your statement about reinstalling the original pump does not compute.
thank you. boomer

 

[jayvee43]

It's the weight of the new float, Brass is heavy and sits lower into the fuel, and the pressure from the pump doesn't help, combine the two factors lack sufficient boyancy to push up against the needle and seat and stop the flow with force.

I bet ya, you go back to your fiber float, and it will work, the few times I saw that problem was the float.

Also, (so no one asks again) is your float filling with gasoline, do the rattle in your hand and listen to seee if there is fluid in it.

 

[Hugh-SS/16]

Yeah x2 on Boomer, could be getting to much fuel from the aftermarket pump. The pulse diaphragm pump on the carb is perfect for the carb.

 

[Ramdeesl]

If it worked with the old float and you didn't change anything else, it will work with the new float. Your problem is with the adjustment of the new float. It proboly is not as boyant as the foam, therefore does not seat the valve and causes flooding. I'm not an expert on carbs but this would seem to make sense, at least to me. Hope this helps. I use elec pumps (1 to 3 psi) on two of my onans and have no problems with them. :dunno: :trink40:

 

[Hugh-SS/16]

Have you adjusted the float gap to spec? You might be letting in too much fuel

 

[motocross77]

Thanks everyone. There is no gas in the float. Also about the fuel pump. It is a DD carb. What i meant was i need to find the other parts to the fuel pump because the only thing that is part of the fuel that is on the carb is the end piece where the fuel line connects too. I will get some pictures of the carb and float later today. I am leaning towards that the pump is too powerful. The pump was on there when i got it so who knows it could be putting out way to much pressure. Also, the float gap is about 1/8"-3/16" and the float only moves up and down like 1/16 of an inch. Is that normal? It moves freely and I can see the needle opening and closing. Could I lower the pressure on the pump by adding another filter or wouldn't that help? The pump is back where the fuel tank is, so there is about 3-4 feet of hosing plus a filter before it gets to the carb. I will tinker with it some more tonight and hope I get it running perfect! Thanks!

 

[ricohman]

Thanks everyone. There is no gas in the float. Also about the fuel pump. It is a DD carb. What i meant was i need to find the other parts to the fuel pump because the only thing that is part of the fuel that is on the carb is the end piece where the fuel line connects too. I will get some pictures of the carb and float later today. I am leaning towards that the pump is too powerful. The pump was on there when i got it so who knows it could be putting out way to much pressure. Also, the float gap is about 1/8"-3/16" and the float only moves up and down like 1/16 of an inch. Is that normal? It moves freely and I can see the needle opening and closing. Could I lower the pressure on the pump by adding another filter or wouldn't that help? The pump is back where the fuel tank is, so there is about 3-4 feet of hosing plus a filter before it gets to the carb. I will tinker with it some more tonight and hope I get it running perfect! Thanks!

Adding a filter will not lower the pressure. You can add a regulator though or a different pump. But by that time you would have spent more than an original pump would have cost.
My tractor ran when I got it but the pump had far to much pressure for this application. Gas would pout down the throat from the top float bowl gasket. And I had installed new gaskets in the carb. Since I rebuilt the original pump it has run very well.

 

[RestMyCase]

The electric fuel pump should have information stamped on it so you can identify the manufacturer and model #. The model # will tell you what the output specs. are. You want 1.5 to 4.0 psig. max ..... If I were replacing the float, it would be a genuine Onan brass float and not a cheesy china brand because they are flimsy and can flex before they close off the fuel supply under pressure . I prefer the vacuum pulse pump but if you already have the proper electric pump it will work fine ... IMHO

:trink40:

 

[motocross77]

I finally got some pictures for you guys. Here is the carb, notice the orginal pump is off. I found the orginal pump but it does not look good. I think that the top gasket on the carb is bad. It looks like it is leaking out of the side of the carb as well as the top. Can I buy just the top gasket instead of a complete rebuild kit? I am ready to through this carb out in the yard and rig on a new more modern carb!! Is that possible?!

Here is another picture of the carb.

Here is the picture of the pump. No markings or anthing on it. mmhhh

Well I am on a role now so I will keep going, a picture of my homemade weight box.

And my homemade plow.