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Question-carbs

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jlaird

jlaird

Great Pumpkin
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The good books say check float level 1/8 inch drill bit between the body and under the lever thing. OK mine are much more than that. However it seems to me that a larger opening would depress the float and allow less fuel in the chamber, ie close the valve sooner thus preventing over flow. Agree??

Now the fuel in the chamber exits the bottom and goes to the bottom of the needle and choke assy. That is where my leak is, I have checked my assy and seems I have put them together correctly. Heck overnite the float chambers have run dry. Ideas??????????????????? Yep I know where the leak is, how in the world do I fix it. What have I done wrong?

I do not suspect the fuel pressure as I do not get overfill of the fuel float chambers as no fuel is pushed out the drain tubes.
 
is it leaking at the needle seat or the float bowl side..plastic hose runs between them on mine, covered by a spiral wire. Might be cracked under the wire....just a guess.
 
Noop, my fuel transfer is inside the carb, H1. I have come to the conculsion that it is an over pressure fuel pump. It just must be, I have had everything apart again and all is fine inside.
 
As for the actual fuel level setting- about the easiest way to check if the floats are set correctly is to take off the dashpots and covers and turn on the electric fuel pump. If the fuel level in the jets is 1/16th to 1/8th inch below the top of the jet (choke handle fully in) then you are good. If the fuel is less than 1/16th inch below the top then you will be running rich. This is of course with the engine OFF!!!
Bill
 
Jack,
An over-pressure pump wouldn't drain your float-chambers dry, though, would it? You must have some other leak.
 
Roger is right Jack, and Leeseat is referring to an H2 setup. How about the washers on the float bowl to carb connection which is where Leeseat is trying to steer you but on a different carb. - how are the rubber washers above and below the through-bolt (Moss diag. # 26 / VB #50 or #s 43 & 44)(too tight, too loose, not creating a seal)? Also check Moss #14 & VB #13- cork seal.
Good luck, hope you find it!
 
Had both carbs off and apart. See nothing wrong. All the insides are new. It is not leakeing at the float chamber to carb seal. It is leaking at the bottom of the choke tube and the mixture nut.

Going to try it again when I get gumption to pull the truck battery.

I don't understand why it would run rich if the float lever is adjusted too far apart ie too open fuel does not come out the overflow? The pump just keeps pumping as long as the fuel has someplace to go.
 
Still leaks. Darn things. I also think the valve seats are too tight, when you let the choke off they do not go all the way home.
 
I have seen a NUMBER of SU's leak at the gland nut for the jet line at the bowl. The REASON is usually that there's a second gasket in there. The old ones can look like part of the bowl and not get removed... kinda like the old oil cannister "double gasket" O-ring leak.

Are your chokes the lever arm type?
 
Yep they are Doc.

YOU AIN'T GONA BELEIVE THIS. The new choke jet tubes were too large, went back to the old ones no leak, had pressure on them for at least 5 min. They also return when you release the choke. How about that sports fans. I thought I was getting stupid.

So today was only changeing timeing 180 degrees and fixing carbs so they really work. Some more effort there tomorrow but I think I got it. Damb vendors. Little cars are not supose to have any leaks darn it.
 
This should convince all to go thru Joe Curto for the carb bits... /ubbthreads/images/graemlins/wink.gif
 
I think you are right again Doc.

Hap in NC also does carbs very nicely. Gets all his bits from Joe who urged him to do them as he has such a back log.
 
Hi Jack, I would go back and set those floats exactly as the book specifies and then check it out again.--Fwiw--Keoke
 
I did, didn't help at all.

I will replace the choke tubes down the road, but has been two hours now and no leak.
 
I had a fellow club member with a bugeye and twin HS2s, he was going thru the rubber jet tube rubber grommets like crazy, might get 100 miles out of one before it leaked, upon inspection they were disolving in the gas. Anyway at the club meeting, he ask me what I would do, I told him I use to have the same problem when I bought VB/Moss carb parts, switched to Curto, end of problem. He took my advice and now Curto and myself are his heros, thats been well over a year ago with no leaks. When it comes SU carb parts for me, It's Curto or nothing. As far as float level, if you are 3/16" or less you should be fine.

Oh and Jack, I'm in the better of the two Carolinas, South Carolina /ubbthreads/images/graemlins/grin.gif
 
Yep, I screwed up Hap. Should have gone to Curto or you for parts to start with.

But, I hereby promise to do so for carb parts in the future.

You see the prob I had with the choke tubes?
 
Live and learn Jack, you're just traveling down a road I already traveled, all experience comes from lesson learned the hard way /ubbthreads/images/graemlins/smile.gif OH yeah, I've seen that problem numerous of times, that and other problems is why I sought out Joe Curto for parts and that lead Joe into talking me into building carbs for the street, I'm glad I listen to Joe, it's been a nice addition to my business and I enjoy building carbs, they are much easier on the back than a MGB engine block /ubbthreads/images/graemlins/smile.gif Carb rebuilding for my shop has been strong this year and thats just fine by me.
 
/ubbthreads/images/graemlins/smile.gif
 
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