: 75 stalling issues



75sled
04-15-09, 09:22 AM
Hey y'all

My 75 coupe is experiencing some issues. The most dramatic started about 3weeks ago. It started out, that when under WOT, it would stall or hesitate throught the whole range of speeds. Then it started doing it all the time no matter how hard or easy you were driving it. Well my first thought was fuel so last night I removed the fuel filter just to see if that would help. Well I noticed when I got everything back together that you could "goose" it and fuel would dump over the top of the carburator and get sucked into the butterfly. Is this normal or is it overloading. If it is overloading could that be caused by not having a fuel filter in place, or is it something within the carbuator?

Also, due to the tightness of the line fitting into the filter holder, I rang off the supply line. So i just cut the twisted part out and replace it with a rubber fuel line. I don't think this could cause a problem, but i just thought I would mention it to make sure.

75sled
04-16-09, 07:53 AM
What??? Nobody has anything on this. Did I get too wordy, or was it not clear?

N0DIH
04-16-09, 09:28 AM
Sounds like the float is dying. Check the float level, see if the float is sinking. My 76 Delta did that and ultimately left me stranded in an intersection when it died off on me. a 4860 lb B Body is not cool to push alone through an intersection....

And as for twisting the line on the carb, you MUST have a 1" wrench on the filter housing and 5/8" line wrench on the line to keep it from twisting. If it still wants to then, spray some PB-Blaster up inside the 5/8" nut and the line. But the 1" wrench is 100% mandatory.

75sled
04-16-09, 12:58 PM
So how do you get to the float to see if it is sinking. Is that a complete rebuild on the carb?

As far as the twisted line goes, i had both but even with a cheater bar i couldn't get enough leverage on teh thing to break it loose. When i finally wrung it off and got it out, I stuck it in a bench vice, and with all my 230lb I was jerking on that fitting and it took about 4 good jerks to break it loose. I was at the point that i thought someone had cross threaded the fitting or somethin. I have never seen one be so tight. Anyway, live and learn.

cadillac_al
04-16-09, 05:29 PM
Fuel coming out the top is always bad. It will have to be taken apart to fix it. some people put a new float needle and seat in on every rebuild. I usually take a chance and not replace it if it looks good but look it over closely.

75sled
04-17-09, 08:45 AM
Seems as if saw a link somewhere around here about rebuilding these q-jets. Anyone have it handy?

carnut
04-18-09, 04:10 PM
The rubber fuel line is setting you up for an under hood fire. The newer fuel is very dry and will eventually cause the hose to leak. New cars have virtually no rubber fuel hoses anywhere because of this. You might try retightening all the upper screws on the carb as well as the four bolts holding it on. If the upper air horn is loose, fuel could escape there. Driving with the filter missing on that old of a car, can cause crud from the tank to enter the carb.

75sled
04-20-09, 08:35 AM
You're right. I agree on both the fuel line and the filter. I was merely trying to find out where my problem was. It hasn't been driven since then because of the sever hesitation, and now stalling at low speed like when you are turning. Afraid of what NODIH mentioned about having to push it by myself. Not interested in going there.

I will try the bolt tightening on the carb. That would be great if it worked.

75sled
04-27-09, 10:27 AM
Just informational here. I put a new filter back in place and it completely stopped the fuel dumping over the top if the carburator. Apparently there is enough back pressure caused by the filter to prevent that.

Anyway, after replacing the filter and tinkering with the timing a bit. My car is much much better. It still has a very slight dead spot, but nothing like it was. I suspect I could still use a carburator rebuild, but for now, it is much much better. Maybe time for a timing gear and chain also. Always something.

Brother_B
04-28-09, 09:57 PM
I have replaced a section of the steel fuel line with rubber hose also. (Actually, on both of my 472's.) I bought a nice pre-bent (CNC) fuel line from the pump to the carb. To get this new one in, do I need to remove a bunch of stuff? There is so much in the way. I really don't want to try to un-bend any of it to thread it in there.

Tzd1310
04-29-09, 07:58 PM
mine had a similar problem, when I started it up the engine would stall and I couldn't figure it out, I had to give it gas all the time or it'd die on me. Turns out the spring that was connected to the throttle cable on the right side was stretched out which caused the problem. Give it a look that's all I can think of