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Bendix puking gas

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dj

Bendix puking gas

#1

Post by dj » Sun Jan 18, 2009 5:38 pm

The Bendix/Zenith I'm running pukes gas thru the filter housing onto my gear cover. My plugs read good...as in chocolate brown or a shade lighter. Do you think maybe I have the idle screw too rich?
Seems like I've read here before about Bendix being notorious for puking gas. Is it an all too common occurance? Any solutions besides going Linkert or CV?
S&S..?? Never! The filter is too common and recognizable, and modern.

Post by fourthgear on Mar 14, 2006, 9:16pm

DJ
I know you may have checked this, but is the float OK , not sticking or out of adj.?

Post by King on Mar 15, 2006, 7:03am

DJ

I agree, check the float. Mine was doing the same thing and I set the float about 1/16 lower than the stock specs I think 5/16 vs1/4 but I'm away from my data right now so maybe some one else could confirm this. Anyway that cured the problem. Another thing to check is the rubber cover on the accelerator pump. Mine has split a couple of times and also just come out of its hole causing spillage. It hides behind the air cleaner and can get ignored.

King

Post by dj on Mar 15, 2006, 10:04am

I will recheck the float. When I rebuilt the carb, it took me a couple of tries to get the thing to work at all. I mean, a steady stream of gas leaking! Maybe I need to set the float just a little bit lower. I installed a new accelerator pump when I rebuilt, and the boot is fine. You guys are probably right-on about the float. Thanks.

Post by jackmoghrabi on Mar 15, 2006, 5:34pm

Hey DJ,

A while back I had the same problem with my Zenith/Bendix. I bought a rebuild kit and installed a new fuel needle valve, accelerator pump, gaskets, float return spring and what not. I adjusted the float per spec. The carb still leaked a nice steady full stream out of the overflow hole in the fuel bowl! I took the carb apart about three times, very perplexed. Finally on the last try I took the brass float in my hand and I shook it next to my ear. Wouldn't you know I heard fuel sloshing around in the float! And what's also interesting is that when I immersed the float in a cup of water, looking for the stream of bubbles to pinpoint the hole or holes, there was none! And the float didn't even sink to the bottom of the cup like I expected her to. Part of her dipped below the surface (where the fuel settled and made her a tad heavy) but the other half of the float had enough buoyancy to stay afloat. I think the brass float had aged to an extent that the brass just became porous enough to let fuel in, maybe on a microscopic level. Anyway a new float fixed her.
My lesson is to shake the float first thing.... I would have avoided a new rebuild kit I didn't really need and being more perplexed than I'd like to be....Good luck. JackMO!

Post by sleeper on Mar 16, 2006, 9:21am
"And the float didn't even sink to the bottom of the cup like I expected her to. Part of her dipped below the surface (where the fuel settled and made her a tad heavy) but the other half of the float had enough buoyancy to stay afloat"
Exactly, & when float is "hinged" we know where the heavy end will be, right ?? opposite the hinge hanging down w/xtra gas/weight inside..

Post by dj on Mar 17, 2006, 6:24am

JackMO....

I will definitely keep that in mind when I open the bowl up. Haven't had time lately because of trying to move to a new house and work. I've already got the bike in the garage there, and getting time to actually ride it or work on it is scarce right now. Thanks for all the advice everybody.

Post by King on Apr 5, 2006, 2:22pm

DJ

Sorry to be late getting back with this but I just found my notes on the subject. A while back my Bendix was weeping gas as you describe and I posted a 'cry for help' on another site that deals with Shovelheads. The responders gave good info on the valve seat/needle and the height of the float. First off, there are a lot of bad Bendix rebuild kits out there with improperly seating needles. The best needle is the one with a rubber nose cone where it seats on the fuel inlet port. The next point is that the consensus among the Bendix aficionados is that the float height should be 5/16" not 3/16" as mentioned in the Harley manual or the truly bogus 1/8" in my tech sheet from Zenith. I disassembled the carb made sure the needle and seat were OK and reset the float height @ a 'fat' 5/16.
NOTE: the 'float height' is measured as the gap between the rear of the float (the point furthest away from the needle arm) and the gasket surface when the carb body is in the inverted position.

The adjustment is made by carefully bending the tab that acts on the needle. Be sure when doing this that an even application of force is applied to the tab so it does not distort. I used pliers with jaws wide enough to cover the whole tab. Also, when the adjustment is complete check to see if any roughness has been created on the surface of the tab that contacts the needle, if so buff it off with very fine (400 or 600) grit sandpaper. This is a good idea in any case especially when the carb has not been serviced for a while and some crud may have built up on the tab or base of the needle. When installing the pivot pin and spring check to be sure nothing is binding and the float has a free range of motion. It is also a good check to suck on the inlet tube when the needle is seated to see if it holds.

That routine cured the problem and it has not resurfaced in 3 years.

Good luck



58flh
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Re: Bendix puking gas

#2

Post by 58flh » Tue Apr 24, 2012 12:32 pm

I have put & ran many BENDIX-carbs.--the originals,-not the GARY-BANG-setups!,they are a great carburator--very easy to tune & jet!-(I am not saying the GARY BANG ones are bad! They are better for a motor with a little cam & stroke-I reworked 1 of his for my 69-shortster & really got ALOT of out of it,picked-up a 1/2second!,-but that was after some machining i thought it needed!(worked out great)-we also put it on a stroked shovel & dialed it in on wed.nights-Englishtown Raceway--Wed.is run what you brung & tune night there along with some side-betting!!!.After the first run it was not even jetted properly yet ,& he beat his fastest time to date!-So BANGS are alot of$$$$ & ineed of alittle machining to get your $$$ worth!-----RICHIE 8)

58flh
Posts: 3338
Joined: Sat Jun 26, 2010 1:54 pm
Bikes: 1958flh 1969sporty,had a knuckle but sold back to original owner
Location: NEW JERSEY

Re: Bendix puking gas

#3

Post by 58flh » Fri Apr 27, 2012 3:46 pm

58flh wrote:I have put & ran many BENDIX-carbs.--the originals,-not the GARY-BANG-setups!,they are a great carburator--very easy to tune & jet!-(I am not saying the GARY BANG ones are bad! They are better for a motor with a little cam & stroke-I reworked 1 of his for my 69-shortster & really got ALOT of out of it,picked-up a 1/2second!,-but that was after some machining i thought it needed!(worked out great)-we also put it on a stroked shovel & dialed it in on wed.nights-Englishtown Raceway--Wed.is run what you brung & tune night there along with some side-betting!!!.After the first run it was not even jetted properly yet ,& he beat his fastest time to date!-So BANGS are alot of$$$$ & ineed of alittle machining to get your $$$ worth!-----RICHIE 8)
I would like to add that alot of the Bendix carbs. have the accelerater pump-shooter always set in a diff. position!--You dont know till you look in there.--Some shoot right at the sidewall of the venturi & splash into the aircleaner! Very-common,& Also easy fix a small wrench & turn where you need it -down the throat.---Richie

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