running problem

[GREASEMONKEY72]

sometimes my truck will try to die on me, itll be idleing fine then for some reason the rpms will start to drop slowly and eventually die if i dont keep it runing myself, now this happens fully warmed up or not, i never know when its gona do it till it does it and if it matters i did let it go to see if it would die and i took the aircleaner off and when it died some fuel splattered out of the carb, thats how i know itll die, i have to 2 foot it to keep it going in gear or not and it really sucks in the middle of traffic

any help is greatly appreciated and thanks in advance

[GREASEMONKEY72]

i did pull the carb and clean it out and sprayed the hell out of it with carb clean and made sure the bolts were tight and that all the lines are hooked up so theres no vacumm leak

BTW, its a quadra jet

[mexgrhd68]

Originally Posted by GREASEMONKEY72

sometimes my truck will try to die on me, itll be idleing fine then for some reason the rpms will start to drop slowly and eventually die if i dont keep it runing myself, now this happens fully warmed up or not, i never know when its gona do it till it does it and if it matters i did let it go to see if it would die and i took the aircleaner off and when it died some fuel splattered out of the carb, thats how i know itll die, i have to 2 foot it to keep it going in gear or not and it really sucks in the middle of traffic

any help is greatly appreciated and thanks in advance

wusup monkey, my 68 used to do the same thing, the only difference is my carb is a holley. My buddy adjusted my air and fuel screws out a little and shazam, she was running good again! hope this helps.

[ERASER5]

Floats sinking? Standard Q-jet problem. Worth a check anyway.

[GREASEMONKEY72]

ok ill check both

its just wierd because it doesnt always do it so its boggling my mind on what it could be

air and fuel screws??= idle mixture screws?

[GREASEMONKEY72]

Originally Posted by ERASER5

Floats sinking? Standard Q-jet problem. Worth a check anyway.

should i tweak it up and see if it still does it?

[ERASER5]

If the floats are a bit heavy, they need replaced. A good time for that is when you have the car apart cleaning it. A carb kit is fairly cheap and can be gotten anywhere. The floats, you may have to order.

Of course the $200.00 fix is an Edelbrock 1406...

[GREASEMONKEY72]

i rebuilt the carb about 6 or so months ago and it didnt come with a float so yea id have to order one

[Hooker]

try and check your vacum advance on the dizzy

[GREASEMONKEY72]

Originally Posted by Hooker

try and check your vacum advance on the dizzy

how do i do that without a vacum gauge? just unhook it and see what happens?

[mexgrhd68]

yes the idle mixture screws.

[sb69chevy]

I have a quadrajet also. Mine does the same thing at all times (always have to 2 foot it). I know nothing about adjusting carbs and have just gotten used to it, I guess. After I get a new tank, I'll probably buy an Edlebrock.

[Overkill67]

dont forget to change the fuel filter(s) you may have a chunk of crap bouncing around that keeps getting in the way. It used to be a major issue when they started adding ethenol to the gas. It of course acts like a cleaning solvent and will loosen and gunk in the tank/lines/carb especialy now that in some areas they have the "special" summer mix that has even more added in.

[nvrforgotten52]

check vaccume leakes first of all tings... if you have a good vaccume gage

[Eichorst69]

It sounds exactly like the float is sinking. The foam floats will absorb fuel over time, get heavy and begin to sink causing the carb to dump fuel. The engine will load up and stall.
Change the float. I've had to change mine twice. You will feel the difference in weight between the new and old.

Rob

[GREASEMONKEY72]

sounds like the float then because the time i let it stall out it sprayed some fuel up out of the carb

would this affect the perfornmance of it to? cause the other day i got on it and it didnt pull as hard as it used to, so i checked the timing but its fine

[GREASEMONKEY72]

well i replaced the float and got it all back together and it did the same thing so i pulled it back off and checked the spec level on the float and noticed that the accelerater pump shaft was in the wrong spot so i moved it and put it back on the truck and it idled prefectly, havnt driven it yet though, you guys think the perfornmence will be back how it was before?

[Eichorst69]

Should run better now. You may have to adjust the float by bending the steel one way or the other depending if the motor starves for fuel at full throtle or the other way if it seems to still want to load up at idle.

Rob E.

[JAKES 68GMC]

My Vw dune buggy used to do the same thing, and it had a new carb on it. Never did figure out why she did it........

[GREASEMONKEY72]

well i took it out for a drive around the block and it doesnt pull as hard as it used to at all, the float level is at spec and the accel pump shaft is in the inner hole, could it be that or could it just be the heat lessening the power or could it be the plugs being dirty?

[JAKES 68GMC]

Probably a holley 600 would solve all your problems and then some.

[eedgell]

Unless you take the time to really get to know the Q jet carb, once they start messing with you, you are better off with a new carb. I would suggest the edelbrock 1406. Or trial and error your carb till it runs good, but it WILL mess up again!

[abebummy26]

my dad swears by qjets he can tune them really well hopefully i will learn it two as long as you stay out of it gas mileage will be better than a holley

[GREASEMONKEY72]

the reason i havent gotten a holly yet is because of the mpg

but i drove it again tonight and at first it still wouldnt go, and btw i havnt done anything to it, but then on the way home i got on it and it went just like it used to, so that tells me its the secondaries not opening like they should

is there an adjustment to help with the secondaries opening or what?

[72chevy327]

Id bet my money on either a float related problem or simple miss adjustments. call a parts guy and find out the presets and tweak from there.