So...Last winter my jeep started stalling at different times. It has the 258 I6 with a weber carb. It was orginally rom califorina. I started by replacing fuel filter spark plugs pvc valve distbuter cap and plug wires. When it stalls it is when I'm driving usually sometimes it stalls at lights. When I'm idling if I keep the rpms up sometimes that will help.....It might not though its hard to say....When it stalls sometimes I can just turn it right over, other times it will just not start and if a wait between 2-20 minutes it will start sometime in beween this time. The motor just cuts out, it seems like it is starved of fuel. When I stopped driving it last march it started this back fire thing(not really a back fire) It was more of a lost of power, huge lost of power I think the motor was almost stallin then it would somethings get more fuel and just keep going and I get power back other times it would stall and I'd have to wait a few to several minutes before it started. Then I would be back on my way. The choke doesn't work it doesn't have that high warm up idle anymore. I've looked at the carb and cannot figure out why it will nit engage. Recantly I've been trying to get my cj7 back on the rode the only way it will start is if I put fuel straight into the Carb, but it will not stay started. Pls. help I miss my jeep it sucks taking the bus matt
Could have been a few things until you said "it will start is if I put fuel straight into the Carb". Tells me it is a fuel delivery problem. you never mentioned if you have tried a new fuel pump. If you have not done so already I would say start with the fuel pump, if you have already tried that I would have you try an electric pump next. And a fresh fuel filter is a given, I would put a new one in regardless of how old your current filter is.
What did you do with the charcoal canister, which is the gas tank vent, when you swapped carbs? A blocked canister or vent line will cause it to act like it runs out of gas as you drive along. Let it sit and it starts back up.
You don't say what year it it, but a bad ignition module can also cause that. Module usually just cuts out, the vent blocked bogs out like no gas.
When you changed fuel filters, did you get the new one in upside down by any chance? The filter has 2 outlets, the center one goes to the carb, the top one goes to the return line. If the return line isn't at the top, then gas will syphon back to the tank when it sits making cold starts a bugger. You need to pour gas in then to start it.
Or all of your symptoms could simply be a hole in the suction side of the gas lines. I usually find the holes where the steel lines joint the rubber ones at the back of the frame and at the front. This suction leak won't drip on the ground until it gets really bad but it will leave a stain mark on the lines so you can find it.
As far as the carb choke goes, what kind of choke do you have? Is it electric or mechanical. If electric, I suspect a dirty connection on it's power plug.
Maybe it's time for a carb kit?
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Running only when you slosh fuel down the carb suggests that it is starving for fuel.
Here's how I'd troubleshoot this -- other, more knowledgeable folk might approach it differently. Don't start replacing things willy-nilly, that's just a good way to waste time and money.
Pop open the hood, disconnect the coil (you don't want the engine to run for this), pull the fuel hose off the pump side of the fuel filter and put a coffee can under it. Gas should spill out. Crank the engine and see if you get consistent, healthy spurts of gas. You should see gas within 10 seconds.
IF YOU DO: There's a problem between the filter and the engine. Bad filter (BTW, you /do/ have the filter installed with the vent port to the _top_, right? That's important.) or crap in the carb. Carb rebuild kits are cheap -- about $25. Pull it apart, clean it well, put it back together. If doing that is beyond your ken, remanufactured Webber 2BBLs can be had for around $250, minus a core of about $40. And that way your high-idle might work again.
IF YOU DON'T: Take the fuel cap off the tank and try again. If you get gas then the vent system is plugged. Ask here for details.
IF YOU STILL DON'T: Bad fuel pump. Pumps for the 258 are cheap, available and easy to install (unless you're working outside in freezing rain). The hardest part will be getting the fittings off without destroying the tubing.
If you've got more time than money, try this before you replace the pump: Disconnect the tank side of the fuel line at the pump and see if you can get a siphon line attached. If you can get gas then the pump is bad. Alternately, pull the cap off the tank, put an air line on the fuel line and see if you can gently blow air back to the tank. If you can pass air it should pass fuel.
REPLACED PUMP AND STILL NO GAS: Rusted-out fuel line. Your fuel lines are steel and can rust, although it isn't all that common. A pinhole will let the pump suck air instead of fuel. Trace the line back from the pump, down along the inside frame rail to the cross member near the tank. From there it jumps to the top of the cross member and crosses over to the left side. Eyeball every inch you can.
Pinched/cracked rubber tubing. If your lines are original the steel line dies out near the cross member just forward of the fuel tank. The line continues on as rubber tubing from there to the fitting at the top of the tank. When I reassembled my `79 CJ-5 I managed to pinch the fuel line between the frame and the body and it took me days to figure it out. A cracked line will let the pump suck air.
Clogged fuel sender. The fuel pickup in the tank is a steel tube that extends almost to the bottom of the tank. It has a plastic mesh filter "sock" on it to screen out dirt and rust. If it gets clogged you can't draw fuel through it. The fix involves dropping the tank and replacing the fuel sender assembly -- ask here for detail on how to do this.
sounds like the classic case of debris in the Weber. There are some fix_its described several places on the net. One of them involves drilling the venturi ports (here is a description for cleaning them .,....... but if you follow this protocol and exchange the piano wire push for drilling slightly oversized, it is identical to the www sites decribing the over_drilling procedure).
The Carb is an after market Weber.....trust me I'm out of town right now but i will be spenting my chistmas and boxing day under the jeep......thanks for tha advice hopefully everything will go fine..........ah do I miss driving it........My Jeep has some blow by could this be causing the problem
What did you do with the gas tank vent when the carb was swapped?
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
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Yes ..... I've seen adverts for that line ...... but I assumed this to be a very different carb ... i.e. sans bowl, float etc. ?????? - and do you know if the carb initially in question here was w or w/o stepper ??
Most folks have no idea just how profound a statement that really is :)
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