I have a stock 86 CJ7 with the 4.2 litre engine along with the weber carb conversion. It's my toy and only gets driven every couple of weeks in the winter. After it has been sitting for that length of time it's hard to start. I never have an issue in the summer or if I started it everyday. But in the winter I have to pump the gas so much to get it to start. What can I do. The engine runs great and is tuned perfectly. Thanks
That sounds to me like your gas line is air locking over time.
On the stock setup, the gas filter has two outlets. The center one goes to the carb and the top one goes to the return line. If the return line isn't up top, the gas will syphon back over time, usually overnight though.
The gas pump also has an anti drain back valve that could be getting leaky.
One other thing that can air lock the line is a pinhole leak on the suction side of the pump. The rubber lines can crack or the steel line leak and just leave a stain. When sitting, it can let air in.
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
Is your choke working? I have the Weber 34/34 and it was the same way before I plugged in the electric choke. You'd have to pump it forever to get it cranked, and then it ran like poop for about 5 minutes. With the choke it cranks right up without any pumping, and will drive smooth as normal right after cranking...
1986 Jeep CJ7 4.2L I6 T176 (restoration in progress)
1961 Willys 4x4 Wagon L-226 I6 T90 (restoration also in progress)
Mine had the exact same problem and was very hard to start, but ran very well...
I am not 100% sure, but this is the only thing I have changed and it is starting much better recently... I cut the rough, corroded ends of my battery cables at the battery and solenoid, cleaned the cable and connections and reinstalled them.
I think the cleaner connections made a huge difference.
I have the same problem. My electric choke is working, but i have to crank for awhile before it will start. The longer it sits, without running, the more I have to crank. It seems as though the carb is "drying-out" and the manual fuel pump has to work for awhile to fill up the carb again. My in-line fuel filter has only one inlet and outlet. Could this be my problem?