Carburetor rebuild leak. Normal?

mtaggart

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Feb 21, 2006
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I put new carburetors kits on a 1984 1 5/16ths cross flow. I also replaced all of the fuel lines. To check the lines for leaks I pumped the bulb to put some pressure in the lines. I noticed the top and bottom carbs were spilling over through the brass fittings between the throats. Is this normal? My thoughts were possibly the floats were not puttin enough pressure on the needle and seat to seal it off, or I was putting more pressure on the fuel system than the fuel pumps will. When I adjusted the float I made sure it was parallel to the body upside down, however, maybe it's just parallel and not the right height. Any thoughts would be appreciated.
 

fireman57

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Aug 24, 2004
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3,811
Re: Carburetor rebuild leak. Normal?

Shouldn't leak. You are correct that your float is not set properly and the needle valve is not seating. Make sure that you soak these carbs and blow every passage out with compressed air. Plenty of threads on this topic, just do a search for them.
 

Jquest

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Jan 16, 2004
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Re: Carburetor rebuild leak. Normal?

I"m not sure about yours ,but on my carbs there is a gasket that sits on the tube(were the two halfs come together) that goes up to the brass outlet. It's in the middle of the carb. The gas goes in through the high speed orifice and up the shaft. If the gasket that sits between the two pieces that come together is not sitting properly...then gas is getting in there and coming up. Since the gas is coming up and out...the needle is not making it to the seat. So no pressure to stop = flow continuing to come up through the top. Hope I made since. :) Happened to me last week when I did mine.
 

mtaggart

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Feb 21, 2006
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Re: Carburetor rebuild leak. Normal?

Thanks for the quick replies. Sounds like one way or another I need to pull them apart. As a note the boat ran great except for the mess that was left when I would pump the bulb and when I would put the motor up all the fuel would drain.<br /><br />I think I may have misunderstood the instructions in my manual and what others have said. Here are two good ones that are similar to others.<br /><br />Carburetor Float Setting)<br />(J. Reeves)<br /><br />"With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked"<br /><br />(OBJ)<br /><br />"Don't forget float seting the other way.....float should set level with the float bowl gasket surface."<br /><br />On this level setting, I would assume where I was off is that I only made it parallel to the carb body and not level. (sounds confusing). Do I almost want to see a little light between the carburetor body and the float when held upside down? Do I do this check with the gasket on to put it even further down in the bowl when right side up?<br /><br />Thanks again.
 

KYHunter2

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Mar 20, 2006
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Re: Carburetor rebuild leak. Normal?

Dont make it more complicated then it is.<br /> As said, level , thats it.<br /> <br /> As you did, looking at side , level with gasket surface.<br /><br /> Then look at front and be sure its level that way . <br /><br /> I use a small "L" guage / square , with fractional increments, to set front level.<br /><br /> I had it from when I worked as a machinist .<br /><br /> Mines metal, some kits come with a cardboard one, thats similar.<br /><br /> Im usually real close, just by eyeballing it.<br /> <br /> You need to check float drop also.<br /> <br /> I've been lucky, and they've been correct as to drop .After leveling float. <br /> But, I've heard of this not being the case, I check it anyway.<br /> <br /> Good-Luck,<br /> <br /> KYHunter :)
 

mtaggart

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Feb 21, 2006
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Re: Carburetor rebuild leak. Normal?

When I had all the carbs off everything sounded straight forward and looked good using my cheesy little cardboard square and my real square. Now that it leaks I've been humbled. Thus the post.<br /><br />KY, I've read a little about float drop in the postings. My manual says nothing of it. What should I look for and how much of a drop do I want. Also the numbers on the card board square had no meaning to me as there was no explanation in the kit. Do I use the numbers to show drop.<br /><br />Thanks again to all.
 

Silvertip

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Sep 22, 2003
Messages
28,771
Re: Carburetor rebuild leak. Normal?

Before you button up the carb, tip it upside down and blow into the fuel inlet line. If you can blow through it you still have something wrong (inlet needle upside down, or ????). If you can't blow through the inlet fitting you are good to go.
 

KYHunter2

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Mar 20, 2006
Messages
512
Re: Carburetor rebuild leak. Normal?

With the carb in its normal running position. <br /><br /> From the bottom of the carb casting to furthest point on float should be between 7/8" -1 1/8 ".<br /><br /> Like I said, I check them , but have never had to adjust , once I had float level correct.<br /><br /> Just follow Upinsmokes test, he's forgot more about these engines, then I know. <br /><br /> Good-Luck,<br /> KYHunter
 

OBJ

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Re: Carburetor rebuild leak. Normal?

Just a note on "level"....using a gage to adjust float levels (special tool) the float will be ever so slightly off level....you really have to look to see it. Telling a guy to set it a tad high can be taken as maybe a 1/16" or larger?? So I do hesitate to tell a guy to set the float just slightly high.....his interpertaion may be more than needed. Level works.
 

mtaggart

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Feb 21, 2006
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Re: Carburetor rebuild leak. Normal?

Success, I think? I wanted to give an update. I pulled the carbs off and re-adjusted the float levels. As a switch the top and bottom carbs did not leak however the middle one then started. I re-adjusted the middle carb float again and it still leaked. I then put another new seat and needle in and the middle carb continued to leaked. I finally adjusted the float a little more, and now everything seems to be holding well. <br /><br />My concern is that I don't feel that I adjusted the float level ever so slightly. I'm about 1/8 inch higher than parallel. <br /><br />Is it better to have my carb leak or the float not level? <br /><br />Will my motor now run lean or will there still be enough fuel in my bowl? Or are there any other issues with the fuel level lower. <br />Thanks to all for the help,<br /><br />Matt
 

fireman57

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Aug 24, 2004
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Re: Carburetor rebuild leak. Normal?

Since you have replaced the parts and it is not leaking and it is running well I wouldn't worry. As long as your float drops enough to let fuel in and shuts off the flow when it needs to you should be fine. If you are running a little lean you will sometimes hear a "sneexe" at idle and then it is time to adjust that carb.
 

Silvertip

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Sep 22, 2003
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Re: Carburetor rebuild leak. Normal?

Sneezing at idle is an idle mixture issue (lean) which is generally not caused by float misadjustment. A lean condition at wide open throttle is a float/jetting problem in that it makes holes in the top of pistons and causes all sorts of nasty things to happen to cylinder walls. Prolonged lean running will cause you to post "she blowed up".
 

mtaggart

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Feb 21, 2006
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Re: Carburetor rebuild leak. Normal?

I went to Lake Powell which is the lowest elevation lake that I am likely to go to and checked my plugs with a wide open shut down. I believe they look good. They are not white or grey kind of a black/brown color. I use the UL77V that dosn't have the electrode. Once again, I believe this is good unless anyone has any other input. Or other test I should use. Thanks again for all the help.
 

emdsapmgr

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Dec 9, 2005
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11,551
Re: Carburetor rebuild leak. Normal?

Did you check to see if the floats in the carbs actually float properly?
 
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