Hard to start after 2 days, fuel drain is possible. Why?

If my car sits for 2 days, I have to crank and crank and crank to get it to kick over and I am baffled. It takes probably 30 seconds of cranking before there is any fire action. And then the car feels like it is flooding sometimes.

I have had 2 different carbs (Q-jets) that have been opened up and looked over many times by myself and Jim Rodgers. I have replaced the vented gas cap also. I have replaced my Stage1 fuel pump with another and I still have this problem. The only thing I have not done yet, and will be my next project is to disconnect the return line to the gas tank. I want to figure a way to make it look like it is all functional.


Any ideas if the return line can cause this or what may help me figure out what is going on?




Thanks in advance,
Mike

 

with todays fuels, I do not believe you going to get away from this, put a aerosol can cap of fuel on our work bench, it will be gone in 2 days, that cap is about 1 1/2 times what your fuel bowl holds, I also have this problem on everything that's not fuel injected, I am going to try out a new needle and seat and accel pump rubber from qjets.com, for the flooding at times, but that still wont cure the evap, I don't believe drain back is your issue

 

Sounds more like choke/tuning problems.

IF you think it is drainback, prove it by removing the carb top.
MOST of the time I see this, the timing is too retarded, the throttle blades are open too far (past the slots), and the choke is mis-adjusted in an attempt to compensate.
(Retarded timing can contribute to boiling off the carb's fuel)
Many other times when everything was AOK, it was just old wiring, poor connections, weak coil and other ignition or wiring issues.

What does Jim think?

 

I do not know what is causing it, but I dont think its drain back. It has me baffled too.

 

X-2, I do not have this problem when the car is on race fuel,

 

As I was writing this up and hitting the submit button, I thought about spark. I have not checked if I have spark at my start up attempt and maybe that is why I am seeming like it is flooding, as it is. I will crank for about 10 seconds, wait 5 or so, crank for another 5 seconds and stop. Then I will hit half throttle twice to see if any fuel is in the carb yet and crank for another 5 seconds to see if it fires off any. Almost always no, and I need to repeat the last step for a slight fire off. This may repeat another time or two before I can finally get it started up and it runs crappy for a while.

I am running the Crane XRI points converter with a MSD Blaster II coil.

As for the carb, I have all choke related items removed, no choke to stick anytime and I deal with the cold nature of carbs. When I am done driving the car, I have a box about 6" tall that I sit on my radiator shroud to prop the hood open and allow heat out of the engine compartment. The primary reason I do this is to keep my GS air cleaner foams looking good, lol.


As for Jim's thoughts... He suggested I block off the return line and see if that helps or corrects the problem and then ask here as he is stumped also. I just have not blocked the return line, I forgot to make a list (A joke between us when he sees me asking on here).


I am really wondering if there is an electrical issue going on and I have no fire. The car runs pretty goon once I get it cleared out after the startup. I am back in the 12.40's at the track. As good as it ever ran.




Thanks all !


Mike

 

Eliminate variables one by one without putting too much thought into it.
A really easy tell is to lay a spare (used maybe) plug on a decent ground to see what exactly the spark looks like, and if it improves a bit after duplicating your starting methods.
I wouldn't overlook your timing and carb settings as the main culprit, even if it 'runs pretty good'.

 

To start narrowing things down, start at the top. An easy test for checking whether or not the float bowl is dry before starting the car is to remove the air cleaner lid and manually open the throttle while looking into the primary side of the carburetor with the choke pushed open. If the first try results in a good squirt of fuel on each side, you know there's at least some fuel in the bowl. If you get more with the second, third and fourth try, it'll give you an idea of just how full the bowl is. Try this after a couple days of sitting. Run the car and try it again after five days parked to see if it's any different.

There are two ways I can think of that the Quadrajet bowl can run dry on its own; evaporation and leaky main well plugs.

Devon

 

it's probably more of a choke issue. plus you all are probably expecting fuel injection starts, simply not possible with a carb. the electric pump instantly primes the system and the start within a turn. plus these big motors turn slower too. this is normal operation for an old rig. check your choke operation and refresh your starting procedure. Lots of folks hop in a carbed car and start pumping the gas until it starts... if your choke is set up properly on a cold start one stab to the floor to close the choke and set the fast idle cam. after that keep your foot foot off the gas and it should start and run. if not, your choke is out of adjustment.

 

I looked at Crane for the XRI. It requires a resistive power feed (from what I can tell). I also need to check the resistance of my Blaster II coil to ensure all is well there. I have been running this combo for 5 years on the road and think it must be OK, but will verify anyways. I will also try to look into my power to the coil from the solonoid. I always wondered what the R was for and now I know.

I plan to remove my air cleaner the next time and look for gas squirting. I drove the car last night, so I will probably check this tomorrow evening if work allows me to. We have battled a leaky main well plug a time or two but think that is not the case right now.


I have a few things to look at in the next week or so, thanks !




Mike

 

here's your sign. you disabled the system that allows for fast and easy starts, now it starts hard.. ou:

 

Modern Fuel Evaporates . After 2 days that is probably what is happening

 

The problem is not the loss of the choke for "fast and easy" starts. Actually a choke does not provide fast and easy starts. It "chokes" off air to enrichen the fuel mixture when the engine is cold to run better and raises the idle during warm up. With it removed, it will never be an issue to choke of air when going down the 1320.

The problem is there is no fire off occurring. Main ingredients for fire are air, fuel and spark. Timing of the spark also matters, but that is not considered a problem as it does eventually start.

I have been thinking all along that I am draining fuel out and it may be a spark issue. I now have a few other ideas to move forward with.




Mike

 

of course you can get by without a choke, but why would you deal with two footing it and poor running?

without the choke, the OP has to manual enrich the carb- pump the hell out of it until it barks. he is only hitting it halfway every 5 seconds. that isn't going to do it. obviously there are two different procedures for a carb with a choke and one without.

also, I'm not sure what the jetting has to do with it. you shouldn't be using the primary or secondary circuit while starting.

 

Mike,

Has something changed here recently, or has it always started this way with the setup you have now.

JW

 

My gut says things have changed. It is harder to start than it used to be. I understand that I have a Q-jet and no choke. I am fine with feathering the pedal some and holding the idle up for 4-5 minutes if needed to idle on its own.


Now I am wondering if I have an ignition problem.






Mike