Pumping the Q-Jet

[Buckskin7T7V]

I have a Q-Jet on my 77. When I first start it up for the day, I must pump the throttle four or five times before the fuel shoots in. Why does the float bowl empty the fuel. There are no external leaks. I am afraid that I will wash down the oil in the motor if I have to keep doing this. It does not require this pre-pumping the rest of the day. Only after it has sat around for eight or nine hours.

 

[brusso]

I don't think that this would cause the float bowl from emptying out, but you could try replacing the in carb fuel filter. It's supposed to go in a certain way and ack like a check valve so fuel wont drain down towards the pump. Again I really don't see how that would affect the bowl. May be some kind of internal leak in the carb. You should see fuel squirting on the first pump, if you look down the throat of the carb holding open the choke.

 

[Buckskin7T7V]

Thanks I will check it out.

 

[Vette/Berlina-coupe]

-another elusive remedy...

-if none of the recomendations given seem to help much, then i submit that your problem is not with the fuel-system, but rather you may have a tired battery, or a junk-battery such as an Exide; --was having the same problem, installed an Optima(sealed, spiral-wound cells) 950-cca Bat., --it now starts INSTANTLY!!! Obviously, in hindsight, the weak battery-current was being sucked-down to the level that there was nothing left to produce a Hot-spark needed to fire a cold engine...
~Bob vH

 

[Yoda]

BuckSkin,

My 81 will drain the gas after about 6 or so hours after sitting. I've been told I can fix this by removing the carb and using apoxy to plug the holes on the bottom of the carb. I guess there are a couple of plugs in the bottom that over the years will begin to leak.

I kind of like the idea that the gas drains out of the carb :L that way I never worry about gas getting old and causing a gumming problem. Also if someone trys to steal her, she puts up a bit of resistance

 

[brusso]

Yes Rare, I believe that the holes you are talking about are on the underside of carb. If you take the bottom section off, you can see two little holes that look like they have little freeze plugs in them. I've heard of people sealing them up during a rebuild. Not exactly sure of what is used to do this though.
Check out this link. It shows the lead plugs the we were talking about. On this site it describes tapping with hammer to reseat these plugs.

http://www.corvettefever.com/howto/53360/

 

[72Mako]

I had the same problem on a '77 Z28. The bowls would leak overnite. I purchased a kit that had you drill out the alumn plugs (located underneath the fuel bowl) and tap them. You then installed allen screws coated with JB weld. I then covered the area with JB weld also. It took care of the problem. Another time, I purchased a beater '78 Chev truck and it started doing the same thing. It also had the tale tell signs of gas leaking in the plug well area underneath the fuel bowl. On that one, I degreased the plug area with acetone and smeared JB weld over the area and it took care of the problem. Charles