My 77 is down and i am so confused. So a while back my chero needed a new carb the one i had started to leak, and was small, only 450 cfm. So i changed out the carb to a brawler 650, it cold started the best i ever had, it was quicker and was so much better...for about an hour and a half... it stalled while i was on the road, lost all power, and just after the stall when you would turn the key the carb would cough loudly, then die. But now it doesnt fire at all and wont start. A small hissing sound can be heard after you try to start it. The carb does squirt when you press the gas pedal. I dont know what to do what does this sound like?
I doubt it is a fuel problem. First I'd check to be sure you have ignition. Then a quick timing check - is the rotor pointed at cylinder #1 with the crank rotated to TDC (top dead center). I write this because I've had a distributor gear come loose while driving. Also not unknown to have a timing chain skip a few gear teeth when all get worn out.
If I had that here I'd reinstall the original carb, see if that runs as well as it ever did before you upgraded it. Does it still spark? Get help if you need to test that.
If your ignition is the OE Duraspark, try replacing the ignition module. They tend to fail while on the road, and you should always have a spare on hand.
That same thing happened to my 66 Ranchero (5.0 engine) turns out the distributor gear pin broke and when the engine would spin, the distributor would not turn on the cam. No start nothing-- Got a new distributor and the problem was solved. Did you have any oil pressure when cranking -- mine showed zero
Just check to see if you've got spark, if NOT, then remove the distributor cap and turn the engine over. Take note of where the rotor is pointed to see if it moves. You can always turn it over until the timing marks line up with zero, and see if the rotor points to the number 1 plug position on the cap.
It's most likely a simple roll pin that shears quite often, very easy to replace, but the distributor needs to be removed. You can usually see through the center of the pin to line up all 3 pieces, then drive out the broken parts of the pin, and drive a new one in to replace it. BUT first you will have to "spin" the oil pump shaft to make sure that it didn't stop turning because of a piece of trash in the pump. 5/16 deep socket (1/4" drive) 6" extension, and you will see the hex shaped shaft at the bottom of the distributor hole - drop down onto it, and see if it turns counter-clockwise. If it doesn't move, the oil pan has to come off and the pump, screen (pickup) and shaft ALL need to be replaced. Good luck.
