My 327 did the same thing, left a local cruise in and getting on the freeway it started running terrible. Would not idle, missing, had to keep pumping it to keep running to get home. Pulled the plugs and one was real wet. Removed valve cover and the exhaust rocker stud on that cylinder had broken off. Also, could it have jumped time?
Sometimes you just get a bad load of gas, which is almost non-existent these days. Run some gas out into a gl*** container and let it sit overnight. See if it separates into water on the bottom, remote as hell but still possible.
I was on a long run with my 40 Pontiac hot rod and had filled up with fuel about 10 miles back and it started to run bad. It is a 4 speed stick and would die when ever you left off for a stop sign and was running rough. I went another 20 miles and decided I had to pull the top off the carb and when I pulled in the parking lot to do it it started to run good and idle! Filled up again with out all the water and was fine for the rest of the200 miles home! Gary
Is there an additive I can add to the tank to help? Octane booster or something like that? Hoping I don't need to drain the fuel tank.
If you think it might be fuel related, Try feeding it fuel from a different source. Try a shot of starting fluid first- if it starts ,,,, Hang a lawn mower tank and gravity feed the carb. "Dry gas" might help.
If it was running fine and then all of a sudden it starts running like ****, it is just 1 thing that has either broke or has some **** stuck in it. If the points/condenser doesn't do it take the top of the carb and look to see if there is any **** in the float bowls, use some gumout in all the holes. I see it is a Qjet, just look at it good and take your time taking the top off. If that is ok put a timing light on it to see if it jumped time. Always do one thing at a time and start with the simple stuff first. If you think the fuel you put in is bad, Then get some gas from a different place and put a small amount in a squirt can / bottle. Have someone crank it and squirt a little in the carb to see if you can keep it running.
ok, plugs wires points coil fuel filter condenser cap rotor carb apart and cleaned...still same, alas broken valve spring! no dream cruise unless my neighbor comes thru with one in the morning! so bummed, guess its the minivan for me
Make sure you have that piston on top dead center when you change the spring. Just in case it gets away from you and drops down. Make sure the keepers are in the retainer properly and you will be good to go.
I went to tow a car that quit on the road. While I was hooking it up, another car coasted to a stop just ahead of the truck. Just as I was about to pull out, a third car stopped. All three filled with gas at the same station and got lots of water.
A way to detect a broken valve spring is to disconnect the coil plug wire.. and crank the motor listening to the rate of revolutions...every time it gets to the compression stroke on the cylinder with the bad spring the rate will speed up...am I explaining that clearly? Posted using the Full Custom H.A.M.B. App!
Did you kick it hard enough to open the carb secondaries when you turned onto Woodward? I've seem secondaries not completely close and cause a rough/flooding condition lots of times before.
I broke a rocker stud before, and while it had a miss, it still ran none the less. In fact I even drove it too work one last time with some duct tape holding the push rod down. I was paranoid the lifter would pop out of the bore, but it still got me another 40 miles before I pulled it apart to repair
I made it! We spent all morning fixing the broken spring and fiddling with the timing. It runs much better, but mechanic friend noticed that when he was working on timing and you hit accelerator it is retarding the timing and said that seems backwards, now I have no clue at all! But it runs, but the quad jet still stumbles, just not as bad.
Sounds like the vacuum advance is hooked up the wrong port. Is it hooked up to constant vacuum or ported vacuum (at idle)? Did you mess with any vacuum lines recently?
No. We pulled the vacuum advance line of the distributor and it runs better. But still stumbles upon acceleration. Also need to adjust the choke to make start up easier
It may be working just fine. If connected to full manifold vacuum, the vacuum advance will provide additional timing at idle above the initial static timing. When you first crack the throttle from an idle the manifold vacuum drops briefly and you could temporarily lose some of that vacuum advance timing. As the manifold vacuum comes back up and engine RPM increases you should regain both vacuum and mechanical timing advance.
That makes perfect sense if you've got a valve that's not sealing, broken spring or not. And if your hearing is good enough to pick it up. If it's an intake valve that's leaking it might even pressurize the intake enough to try to push air and fuel vapors back up thru the carburetor. I'd guess that you could also detect the problem by doing a closed throttle cranking manifold vacuum test. Seems like it should cause a fluctuation on the vacuum gauge when it comes around to the leaking cylinder.
That all sounds like great advice. Although I don't understand wtf you are talking about. Hahahaha. But seriously I don't. Still learning, I'm in the engine 101 cl***. Lol
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