Vintage Mustang Forums banner

1 - 7 of 7 Posts
G

·
Guest
Joined
·
0 Posts
Discussion Starter #1
Hi, I am trying to start my car with my rebuilt holley, but the thing right in the back of the secondarys is shooting out gas all over the place. I don't know what the thing is called , but it is the tall sphere shaped thing right behind the secondary's. What could this problem mean?? Never buy used carbs? Im screwed ? what? Thanks.
 

·
Registered
Joined
·
923 Posts
That should be your float adjustment.
You use a wrench and a screwdriver to adjust this. If you just want to get it started you should close the unit. Use an open end wrench and just tighten it.
the unit is used to adjust the float level in the secondary bowl. On the side is a bolt you remove that will let gas drip out of the bowl. When the car is on level ground you loosen the float adustment screw, while the car is running, and the center of that top assembly has a screw in it. You then turn the screw to adjust the level of the bowl so that fuel just drips out of the hole on the side that you took the bolt out of.
I recommend you get a book on Holey carburators. they are not that difficult to work and the book will help a lot.
No your not screwed.
go to to this link and look at item # 94, that assembly is the float adjustment assembly

www.holley.com/HiOctn/TechServ/TechInfo/f4150-60.html

Dave

I re-read your post, If it's the tube shaped unit that sticks straight up. It should be a float adjustment to fix this. You floats are either adjusted incorrectly, are sticking or could have some trash in the float needle that is causing the needle to stick.
 

·
Registered
Joined
·
194 Posts
The thing spewing the gas is the bowl vent, I believe. Gas will come up out of it when the float level is set to high, or the needle valve is stuck and isn't shutting the gas off. Try tapping lightly on top of the bowl. Sometimes that will free a stuck needle. To adjust the float level, remove the sight plug on the side of the bowl, loosen the nut or screw on top of the bowl and turn the adjuster nut on the needle valve, ( I don't recall which way offhand, and my Holley book is out in the car shop). It shouldn't take too much turning to see a change in the fuel level at the sight plug hole. You want the fuel to just be sitting in the threads of the hole, not running out. If this doesn't help it could be a problem with the needle and seat assembly and then the bowl will have to come off. My brother-in-law's Ford pickup was doing that after sitting for awhile. He wanted me to look at it, but by the time he drove it out to my place it had stopped and everything was dry. Something just stuck. Hope this gives you some info. I know I'm not the best at explaining things. Good luck!
 

·
Registered
Joined
·
4,926 Posts
By the way, if you are having to drain any gas out of the float chamber, a tuna can works great as it is shallow enough to fit between the manifold and the base of the carb. that way you can work on your carb while it is still on the intake.
 
G

·
Guest
Joined
·
0 Posts
Discussion Starter #5
Good tip SR, Im Portuguese, so I have plenty of tuna can's laying around, ill give it a try. Thanks for the help guys, I will check it out tommorow. Btw. I can't get the car running, but is there anyway to check float without car running. Should I just turn the top secondary float screw all the way counterclockwise?? Thats the way to lower it right. Also, If I lower the float and raise it over and over can that free up the needle?? Im clueless. I need a book on these carb's. Thanks.
 

·
Registered
Joined
·
4,926 Posts
Realistically, the quickest and surest way to deal with it is to drain the gas from the reservoir, usually by backing out one of the lower corner screws. Then, unscrew the 4 screws and pull off the float reservoir. Be careful undoing the screws cause there are small washers that tend to stick to the resv. rather than coming off with the screw! You can remove the needle and blow out the seat area with compressed air (a can of compressed air used for cleaning computer keyboards works well). With the needle reinstalled, you hold the part horizonal and measure the drop when the needle is fully closed. There is a spec for this distance, but I don't know what it is. In the old days, you bent the tab on the float to adjust the float level, but with the new double pumpers, the adjustment is different. On my speed demon carb, you have a sight class window in the side of the resrv. and it has level markings on it. You just turn the adjusting bolt on top of the reservoir and watch the gas level move. Good luck!!!!
 
1 - 7 of 7 Posts
Top