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Hey everyone!
I recently purchased a 1989 Grand Wagoneer 4WD - V8, carb, auto. and have had a few issues which I'd like your help to diagnose and a couple of questions to go along with it. Although the car is in relatively pristine condition, I don't have any service records on the car, unfortunately. So far I've done the alternator on the car and the spark plugs, but that's it.

Flooding / Not starting?
So I'm new to carb cars, and know that they can sometimes be tricky to get started, but I'm surprised at how tricky this is to do - I try to start the car usually with one pump, no success, then a couple of pumps, no success. So much so that a few times I've been stranded before and have needed to get the car towed. This type of behavior has happened about 5 times already within the past week and happens when the car is warm or cold, doesn't matter.

Question: Is this normal behavior that I need to simply learn how to start this type of fuel system? or does the carb sound to be faulty and or needs to be serviced?

Stalling while driving -
I've already read on here that this could be related to the ignition control module but wanted to describe what's going on so that you guys could help me diagnose it a bit further before I bring it to a shop to have it looked at.

Situation: I had been driving the car for about 10 minutes when this happened: I went to make a u-turn - and half way into the turn the car died in the middle of the road. Once it was put in park, it turned right over, but not sure why that happened.

Question: Any idea what this might be related to? Perhaps I need to explain this situation to a shop and they could help me diagnose it further but I thought to ask here first so I could have an idea before heading to a shop to get the work done.

Thank you in advance for your help!

Jonathan
 

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Flooding / Not starting?
So I'm new to carb cars, and know that they can sometimes be tricky to get started, but I'm surprised at how tricky this is to do - I try to start the car usually with one pump, no success, then a couple of pumps, no success. So much so that a few times I've been stranded before and have needed to get the car towed. This type of behavior has happened about 5 times already within the past week and happens when the car is warm or cold, doesn't matter.

Question: Is this normal behavior that I need to simply learn how to start this type of fuel system? or does the carb sound to be faulty and or needs to be serviced?
Cold start routine should be a plke or two on the accelerator. This allows the choke to close and puts a squirt or two of fuel down the carb throats.
So, I would start by insuring the choke plate closed when the throttle is depressed. If it isn't then it needs to be adjusted. if it is closed, then check to insure it opens then the engine warms up.
Next, check the accelerator pump.
With the engine off, remove the air filter. Looking down the barrels, pump the throttle. You should see two streams (2bbl) of fuel squirt every time you open the throttle. If you get dribbles or no fuel at all, then you need to fix the pump or check the float level.
 
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It is two pumps, if the carb linkages are set up properly and choke functioning, this will put the throttle butterfly slightly open.

To be honest it sounds like a badly adjusted choke, but I suggest taking the carb off and rebuilding it with a $15 parts kit and lot sof cleaner and then set it to the factory settings including the floats. It i snot tricky, just follow the instructions and do it in a bowl to catch the small parts

Also check the fuel filter is correctly installed. Having it in the wrong place or orientation can drain the fuel down to the tank.
 

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It is two pumps, if the carb linkages are set up properly and choke functioning, this will put the throttle butterfly slightly open.
Bagus, you live in a warmer climate, so yours may not close all the way. In cold weather, the choke should close all the way on the first pump. It should only open (app 3/16") after the engine starts due to the choke pull off, which uses engine vacuum, engages.
Both how tight the choke closes (timing) and how far the pull off opens it are adjustable. If you rebuild your carb, all this should be in the tech sheet that comes with the kit.
Stalling while driving -
If this happens again, you need to hop out and check to see if it has spark and/or fuel.
 

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JD, you may not have grasped the significance of the throttle butterfly valve when choking.

We have not seen the exact make of carb (which may have a separate choke circuit) but on common CJ carbs the choke opens the butterfly throttle valve a tad.

The choke plate is not fully closing the airway, it is working with the butterfly valve to let in some air but creates a lower pressure in the venturi than you would normally have, the difference in pressures forcing the fuel from the bowl and out of the main jets.

Both the common CJ carbs, the BBD and MC2100 have the choke connected through a linkage to a cam that pushes against the fast idle screw (not the curb idle screw, that is a different screw). You press the throttle when cold and it will take the pressure off the butterfly valve, pulling that fast idle screw back and the cam will slip round. The fast idle screw then lands back on the cam but is now being held off further.

Pushing the throttle will also force in fuel via the accelerator pump straight on to the top of the throttle butterfly valve. In fact you can start with just this if you pump enough times but the engine will be lumpy, the choke does it all so much better.

You may have noticed that when it starts cold the revs are high, slowly dropping. this is the action of the cam and fast idle screw holding the throttle butterfly valve open further until it warms up, the cam drops down and the throttle butterfly is held only by the curb idle screw.

I hope that explains why on the common CJ carbs the throttle butterfly is slightly open with choke. If you do not have this working, the carb is pulling the mixture through the idle air bleed and it will not be as rich. I have seen quite a few carbs where part of the mechanism is missing and the fast idle screw does nothing.
 

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No, I grasp it.
The throttle plates open when the choke closes because the high idle screw rides up the cam. This is one reason why the throttle needs at least one poke.
However, the choke plate does close fully when engaged in cold weather. It doesn't open till manifold vacuum hits the choke pull off. The colder it is, the tighter the choke closes. The tension can be adjusted by rotating the cover. The tighter the tension, the longer the choke stay's engaged (duration). In warmer climes or when the engine is warm, the choke plate closure can vary from barley closed to wide open.
Most pulloff's can be adjusted. Depending on the carb, the adjustment can be by bending a linkage or a set screw.
Regardless of which carb we are talking about, these rules apply.
 

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The choke plate is not fully closed on startup, both of the common carbs have ways of pulling the choke plate open to take up the slack in the spring of the electric choke coil when starting. Both the BBD and MC2150 have an initial choke valve clearance that is set up in different ways. This will give a clearance of about 0.14" or 0.116" respectively to let a little air past the choke plate. At the same time the throttle butterfly is cracked open.
 

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Jonathan,
Just a guess that you are younger, drive FI/computer controlled vehicles, where you put the key in and go.
You do have some mechanical aptitude, and willing to learn, or you would have never purchased a carb vehicle.

A couple suggestions

1-If you are trying to diagnose a problem, so you can send it to a shop for repair, save your "shop money" and fix it yourself.
(Like going to the Dr for a problem, and telling them "I looked this up online, and this is what I think it is".......most give you the old sideways look and you know they wish you would just go away.)

2-Find another Jeep owner of the older types in your area (any of the old CJ5-CJ7-Wagoneer-old military types-etc), who you know works on their own vehicles, pick and choose who you will introduce yourself to and ask if you can have some hands on help with your rig. Or maybe ask if you can help with theirs, as carb vehicles typically all work the same, so what you can learn or be taught can apply to your own vehicle.

If you are not comfortable doing the introduction thing, let us know the general area where you live, and another FSJF who lives nearby can message you direct to meet up.
Surprising how much help two heads are better than just one, and what happened to me when I joined after buying my first Jeep, an '81 CJ5 Base model. An existing JF member messaged me one day, one to welcome me to the site, but also to let me know he lives within 5 miles of my house. We have been good Jeep fixing friends since.

If you are near me in AZ, I would be just tickled to come by and help how I can, as I am looking at a FSJ myself right now. But even without that, I was raised on a farm/ranch, 61 yrs old, and much prefer a carb vehicle over this new stuff.

Hands on is the best teacher.....at least for me :)

Forgot to mention...JD2000 and BagusJeep above...if you are good with written instructions, they can help you build a space shuttle in your back yard. Tons and tons of good and accurate information and about anything/everything Jeep related. Trust their info!

Hey everyone!
I recently purchased a 1989 Grand Wagoneer 4WD - V8, carb, auto. and have had a few issues which I'd like your help to diagnose and a couple of questions to go along with it. Although the car is in relatively pristine condition, I don't have any service records on the car, unfortunately. So far I've done the alternator on the car and the spark plugs, but that's it.

Flooding / Not starting?
So I'm new to carb cars, and know that they can sometimes be tricky to get started, but I'm surprised at how tricky this is to do - I try to start the car usually with one pump, no success, then a couple of pumps, no success. So much so that a few times I've been stranded before and have needed to get the car towed. This type of behavior has happened about 5 times already within the past week and happens when the car is warm or cold, doesn't matter.

Question: Is this normal behavior that I need to simply learn how to start this type of fuel system? or does the carb sound to be faulty and or needs to be serviced?

Stalling while driving -
I've already read on here that this could be related to the ignition control module but wanted to describe what's going on so that you guys could help me diagnose it a bit further before I bring it to a shop to have it looked at.

Situation: I had been driving the car for about 10 minutes when this happened: I went to make a u-turn - and half way into the turn the car died in the middle of the road. Once it was put in park, it turned right over, but not sure why that happened.

Question: Any idea what this might be related to? Perhaps I need to explain this situation to a shop and they could help me diagnose it further but I thought to ask here first so I could have an idea before heading to a shop to get the work done.

Thank you in advance for your help!

Jonathan
 

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The thought of having another FSJ Forum Member get in contact with you, is they are already within a trusted audience of other owners, and doubles your resources for information and skill sets.
Chances are, they have already been through what you are going through, or have watched someone else go through it and found a solution to help you with yours.
 

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j-tec......where did you go?

We like confirmation of results, what worked and what did not.
Helps others if it helped you.
 
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