79 CJ7 258 Weber carb conversion - no electric choke wire on Carter carb

'79 CJ7 with stock 258. Not the original engine. When I purchased it in the late 80s, all the pollution stuff was gone. Live in Indiana and no emission testing. Carter carb has given out - needs a rebuild, so I thought I'd do the upgrade. The kit is ordered along with a pressure regulator. Been reading instructions online and keep seeing references to the electric choke wire. I don't have one.

I've been marking hoses and trying to get prepared for the install. Assuming the PO never hooked it up, but assume I can/should. I'm also assuming that it is a simple 12v powered via the ignition switch. Any pictures of the stock Carter setup would be helpful too.

Any advice/guidence appreciated.

Barry

 

You are rebuilding the original Carter BBD? Is the carburetor the correct one for 1979? If so, as far as I can tell there is no electric choke on a 258 in 1979.

Here is the wiring diagram for '79 for the Cherokee and Wagoneer http://oljeep.com/gw/elec/79/79_FSJ_WiringDiagramPage2.jpg - the under-hood wiring should be the same as the CJ. It may be a little confusing, but both the V8 and 258 (I6) wiring is shown on the same diagram. You can see that the V8s have an electric choke wire controlled by an oil pressure switch. The 258s do not - they have a thermostatic choke that is controlled by hot air from a stove in the exhaust manifold. AFAIK this did not change to electric until 1981, when the manifolds were changed.

Does your choke cover have a place to connect a wire?

 

Oh, I should read the title. The Weber is the upgrade.

Assuming the Weber kit you ordered has an electric choke, you will need to add a wire to power the choke. You can order a Weber kit with a manual choke, if you prefer.

I would mimic the diagram for a V8 and connect to splice H. This will be inside the wire loom, wrapped in duct tape. Unwrap the duct tape and solder a new wire for the choke to the splice. The wrap it up in another piece of duct tape and put it all back in the loom.

You can choose to use an oil pressure switch (OPS) like the V8 app, or not. With the OPS, the choke will not start to open until the engine is running. Without it, it will start to open as soon as you tunr the key. This likely won't be a problem as long as you don't leave the key on in cold weather.

 

Perfect! Thanks. Just got the kit and here is what it says in the "Troubleshooting Guide" -

E. Testing the thermostat assembly
The electric chock terminal must have a key hot 12 volt source. The carburetor is grounded the the engine by a metal to metal connection. If the vehicle was originally equipped with an electric choke and or an idle solenoid use that wire. If you do not have a wire present, splice into the wire leading from the ignition switch to the coil or ballast resistor. Water chokes must have a free flow of engine coolant.

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Thanks for the help!

Barry

 

OK, the carb is off and boxed. I can't tell how the choke line (no longer used) is connected to the manifold. Suggestions of what to do with this? Sorry, can't post a pic yet.

Also, would you use gasket cement on the carb gaskets?

Thanks,
Barry

 

Is your intake manifold iron? A '79 should be. If so remove the tube from the manifold and you are done. The end of the tube should pull out of the pocket in the manifold.

Re gasket cement, I would not.

 

First, trying to figure out why I can't post pictures. Anyway, carb is mounted and I'm trying to hook up hoses. There are two hoses on top of the cover. With the old carb, the front hose went to the canister and the rear went to the carb. From what I've seen the front one goes to the PVC attachment on the lower plate. Then there is the "Flow Bowl vent" on the carb. Does this go to the canister or the rear of the valve cover?

Sorry no pictures.

Barry

 

I can't tell you about the Weber specifically.

By cover you mean valve cover? Those are PCV hoses. The PCV system will be shown in the '79 TSM. You do have a copy of the TSM?

The PCV system has two hoses - an inlet from the air and an outlet to the manifold. It takes clean filtered air from the air filter or a separate filter and sends it into the crankcase. The PCV valve side sucks the crankcase vapors into the intake manifold when engine vacuum is high enough to open the PCV valve.

"Flow bowl vent" may be a typo for float bowl vent.

Do you have the original vapor recovery system in the Jeep? If the PO removed that, it was an ignorant act. Look at your TSM about the vapor recovery system. You may want to put it back. It vents your fuel tank and carburetor float bowl, and is 100% an asset with zero performance penalty.

 

As stated in my first note, I purchased this jeep in the late 80s and the pollution equipment had been removed. The PO had swapped engines and didn't put the equipment back. I'm going to put the hoses that I can identify back as they were with the Carter.

Looking at the diaphragms, I'm think I have a place for everything to go. Still need to build a bracket to hold the fuel pressure regulator.

Thanks,
Barry

 

Just did a test run. Wow, what a difference. Like having a new engine. One of those "I wish I had done this years ago" deals. I really appreciate the help and advice.

Thanks,
Barry