Jeep quit starting HELP

[HOTRODVAN]

33's or 35's

I'm trying to sell my sister's Jeep. All the sudden, it doesn't start. It turns over...I've got spark... I've got fuel to the carb., but no fuel going into the venturies. The pins for the stepper motor aren't moving when the motor is turned over. Does the stepper motor only control the mixture when the Jeep is running? Or can it prevent fuel from going into the carb? Any thoughts? Thanks!

 

[Jeepskate]

Sounds like a carb problem. The stepper won't completely block fuel passage. In fact the bypass for the stepper actually instructs you to trick it into completely closing and the disconnecting it. Check to see if there is fuel injected into the carb throat when you open the throttle. If you don't see a stream of fuel entering the carb throat, the float is stuck or something else is plugged up. Maybe the fuel filter? Try squirting a little starting fluid in the carb and then turn over the engine. If it doesn't fire, then there is something amiss with the ignition system. Timing, fowled plugs, something like that.

Good luck

 

[HOTRODVAN]

Thanks Jeepskate! The fuel filter is new (the old one wasn't bad). The fuel is making it to the carb, but none is squirted into the venturies when you open the throttle. I have spark, just no fuel in the carb.
If the floats were bad they would sit on the bottom and it should flood the carb. If they were stuck up high it would shut the fuel off. I took off the fuel line where it screws into the carb and I could see the floats. There didn't seem to be any fuel in the bowl to make them float. I could move them with a small screw driver so I don't think they are stuck.
The manual that I have says that when you start the Jeep, the pins for the stepper motor should move and set themselves. Mine don't move...???

 

[Jeepskate]

The Stepper doesn't control fuel flow into the carb. It attemps to control the fuel/air mixture entering the engine, based on load, temperature, etc. At this point it doesn't really matter if the stepper is functioning, the jeep should still start, just wouldn't run well. So I think the stepper motor is no the immediate problem.

You say there is fuel getting to the carb, but that when you looked into the fuel bowl, there was no fuel. Is that correct? If this is the case, all I can figure is that the needle valve is stuck shut for some reason. How long has it been since the jeep was ran? Old gas can gum things up pretty good. The needle or float may have been dislodged causing the needle to stay closed. Was the jeep running when it was parked last?

I would verify that fuel is actually getting to the carb by pulling the fuel line at the carb, placing it in a pop bottle or other container, then turn the engine over a couple times. You should get gas in the container. Maybe you've already done this, but this would eliminate a bad fuel pump, or plugged line.

It's a bit tricky to get the top off the carter carb and then back on in the right way. But if you're mechanically inclined enough, a new needle would be cheap fix.

 

[HOTRODVAN]

That's correct. There was no fuel in the bowl when I unscrewed the fuel line. I thought that was odd. Ya know when I tested the fuel pump, I took off the line at the fuel filter. Maybe the line between the filter and the carb is plugged. I can't imagine that it is though. It's a 5/16 line I think.
The fitting that the fuel line screws into on the carb has a needle in it. Do you know how that works? I'm going to look it up in the manual too and see if it says anything.
Thanks again!

 

[HOTRODVAN]

I FORGOT TO ADD THAT IT DID RUN THE DAY BEFORE JUST FINE. I took it to get emmissions and the next day it didn't start. I should also tell you that the motor has major blowby that has been getting into the air cleaner. I sprayed carb cleaner down the carb and put in a bottle of emmisions stuff before I took it to pass emmissions. I drove it quite a bit the day before it didn't start. I did get gas into a bottle when I disconnected the fuel line at the filter, but I will check the rest of the line.

 

[Jeepskate]

Sorry to put you off so long. I lost track of things. Did you get it all figured out?

I don't know what to think. If it was running fine the day before, and your getting fuel right up to the carb, but none is making it to the fuel bowl, then all I can figure is that the needle valve some how stuck shut. Maybe the float got itself stuck too. It might be that your fuel pump isn't producing enough pressure to open the needle valve. This would be pretty unlikely I imagine.

It would be highly unlikely for a fuel line to actually plug. Especially after the filter. I guess it could happen though if a chunk of hose came loose or the filter broke.

Your blow-by won't have an effect on the fuel getting to the carb, but it is another problem you should get worked out. It can be a sign of serious engine problems to come. Check out some of the other threads the have to do with PCV systems and blowby. It's a pretty common problem with the 258.

 

[HOTRODVAN]

No worries. I've been busy too. I figured out that something was blocking the hole at the needle and seat. I gently stuck a piece of coat hanger in the hole and I now have fuel. I go to try and start it, and there is now no spark! I have been all over this thing trying to get this one figured out. It's now at a friend of mine's shop, but check this out!
It has no spark while you are turning it over, but when you release the key back to the run position, it shoots a spark from the coil. I have the correct voltage to the coil. I have tried another used coill that I know works. I've replaced the ignition switch, ignition module (2 times in case we had a bad one from the factory) and the magnetic pick-up. I'm now at my wits end with this damn thing. It must be jinxed! It just doesn't want to be fixed. Thanks for your input though! I really appreciate it. Trevor

 

[Jeepskate]

oil pressure gauge is wacky????

Good news on the fuel. The ignitions a little puzzling though. If I remember right, there is different voltage applied to the coil, one ~ 8 volts during "run", and another at full vultage ~12-14 during start. Mine has since been wired a little different, but I think the full voltage is applied through the starter solenoid when the key is in the start position. It might be that the wire got disconnected or jarred loose while you were figuring out the fuel. Have someone crank the engine while you check the voltage with a voltmeter on the positive side of the coil. If it reads zero or something pretty low, then I would suspect a loose wire somewhere. You can run a wire from the positive terminal of the battery to the positive side of the coil. If it runs, or has good spark then you've found the problem. Just remember the engine won't turn off with the key. You'll have to pull the wire. I've had to hot wire my jeep this way when I broke the iginition switch. I wouldn't run it for too long like that though. I think the stock coil is to weak to handle the full 12 volts for long.