I have a 85' CJ7 with the original 258ci straight 6. Problem: Major difficulties starting when cold. It turns over strong, but will not start. Once its running. It runs strong and starts without incident. I have put in a new fuel pump and rotor, and have rebuilt the Webber carb. Any ideas? Thanks.
You probably have looked, but I had a tear in vacuum hose where it bent under carb. Looked fine until I really stretched it straight. It would try and start, and crank intermittently until it got to far gone. Easy solution and good place start.
Ok so I thought my problem was fixed but its not. Turns out I am not get fuel to carb I guess. I just pour a few drops directly into the carb and it started right up. Then it ran fine until I turned it off. What would you all recommend to do first. I just replaced the fuel filter and lines from the electric fuel pump to the carb.
I was having a similar problem - jeep would run but when I left it sitting for any period of time, it wouldn't start. checked the ignition module, coil and distributor and was getting a good spark. Also ran through the entire fuel system and everything seemed fine. There were 2 very simple issues.
First thing you want to check is that your fuel filter is installed correctly. The 2 outlets need to be positioned properly - the line running to the carb must be at 6 'o clock and the return line at 12' o clock. If installed upside down or sideways the fuel has to fill the filter before it will pump into the carb...gravity needs to do its job.
Second thing to check is the needle valve on the fitting going to the carb. Problem I found (after wasting several hours looking everywhere else) was that the needle valve was sticking. Took out that fitting and noticed that the needle wouldn't fall out. Tried to blow it out with my mouth (gotta be able to blow 10+ psi), and wouldn't move. Fuel line only has about 7 psi... Got a new fitting and needle valve with a rebuild kit ($20) and since replacing it, the jeep starts great.
You need to be methodical about your investigations and test rather than assume and replace.
I have picked up that you have an electric fuel pump of unknown capbilities, a three way fuel filter and a Weber carb,type unknown.
First thing is to check the ignition is working correctly, a strong crisp spark. Check you have battery voltage (12V) at the coil in Start and about 7V otherwise.
Next thing is to check fuel flow. You have an electric pump so unhook the line from the carb and put it in a bottle.Turn on the ignition and see how much fuel you get.
If you get a good amount it is not the fuel supply.
Next take the top off th ecarb and pump the throttle linkage. If you get a good spurt of fuel you have fuel in the carb.
Next thing to check is choke and mixture. Get yourself a manual and chack the choke is set up properly. No offence intended buit also check you are following the correct procedure for starting with that carb.
Last thing is to check all vacuum hoses for splits etc. And then the manifold gaskets.