New front harness, flat batteries

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m3a1
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Re: New front harness, flat batteries

Unread post by m3a1 » July 19th, 2018, 1:58 am

Look inside the cap. If it is a valve-type cap, you will find a little wing-looking piece of metal that pivots on the center stud. There will also likely by a stamping indicating open or closed. Simply rotate the metal piece to the desired position.

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Re: New front harness, flat batteries

Unread post by Skureal » July 20th, 2018, 4:03 am

I think it is the best idea for now

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Re: New front harness, flat batteries

Unread post by TraceL » July 20th, 2018, 5:25 pm

So far, no luck with getting the Jeep to run correctly. I checked the gas cap and it was set to open. I even tried my old cap just in case the new one was defective but got the same result. I disconnected the fuel filters that lead right into the carburetor and the fuel dumped right out the end, so I don't think they were clogged. I blew threw them and it seemed to flow fine. Checked the in tank filter, and it was good. Disconnected the and checked the vent line from the tank to the air cleaner and it was clear. I even ran the jeep down the road with the gas cap off (worked better maybe, but couldn't really tell). None of these seemed to solve the issue. I can drive it for a few miles and then it starts to act like its running out of gas (tank is 2/3 full). If I push the clutch in and rev the motor a few times, it will backfire and seems to run better for a few seconds. I know its not the carburetor because it will run the same no matter which one I use. The first time I took it out and had this problem, I was able to drive about 15 miles at speeds between 30 & 55 before it started to act up. Now I can only get a few miles down the road before it happens. Should I start a new Tech Discussion with this since the original electoral issue has been solved?
1962 M151

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Re: New front harness, flat batteries

Unread post by rickf » July 20th, 2018, 6:31 pm

You are describing all of the symptoms of a coil going bad. If you sit for a few minutes it probably runs great for a little bit and then does the same thing but is less time. Eventually it will no longer start.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: New front harness, flat batteries

Unread post by TraceL » July 20th, 2018, 8:24 pm

I will try the coil next. Where is the best place to get one NOS? I know there is a lot of junk Chinese knockoff coils out there.
1962 M151

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Re: New front harness, flat batteries

Unread post by rickf » July 20th, 2018, 8:25 pm

Search Ebay and such, I know of one that just sold for 240.00.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: New front harness, flat batteries

Unread post by Mark » July 20th, 2018, 10:36 pm

I asked a vender, he wanted $275,
mark


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Re: New front harness, flat batteries

Unread post by TraceL » July 22nd, 2018, 7:58 pm

No luck with a replacement coil. I still get the same result. Engine runs great for about 5 minutes of driving and then it starts to shutter and act like it’s running out of gas. It doesn’t happen at idol. Only while driving, and only when I start to get heavy of the gas. Once it’s starts, it eventually stalls (unless I baby it home) after it sits for a few minutes it fires right back up. It seems like it will idol all day long. I figure it has to be related to fuel or spark.
1962 M151

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Re: New front harness, flat batteries

Unread post by old dodge guy » July 22nd, 2018, 9:04 pm

Does this vehicle have one of those vent/nonvent gas caps, after driving a bit it creates a vacuum on the tank? That could starve it for fuel.
Still crazy after all these years.
The OD bug bit me in 1970......and I have never been the same

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Re: New front harness, flat batteries

Unread post by TraceL » July 22nd, 2018, 9:39 pm

It does. Both gas caps I tried (one brand new, and the original) were in the “open” position. Once I figure out how to send pictures on here, I will post some images of my setup. I installed an a2 harness and switched over to the mechanical fuel pump from the in tank electric one I was previously running.
1962 M151

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Re: New front harness, flat batteries

Unread post by Fil Bonica » July 23rd, 2018, 9:50 am

If it is fuel starvation you could test things by disconnecting the fuel tank and connecting the fuel pump by a hose to a known good clean source of gas such as a gas can.
Running the engine this way eliminates any problems with the tank cleanliness, tank filter or sucking fuel through the existing electric pump.
Just a thought!

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Re: New front harness, flat batteries

Unread post by TraceL » July 23rd, 2018, 11:46 am

I think I’m going to try and reinstall the electric pump setup and see what happens. I know with the a2 harness, there is no power for the pump. I’m guessing all I need is power from the pump, to the breaker, to the on/off switch. Is that correct? If so, which lead do I tap into for power on the switch? The 12 or the 27?
1962 M151

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Re: New front harness, flat batteries

Unread post by rickf » July 23rd, 2018, 12:44 pm

Do you even know if the electric pump works? It is 24 volt and you would tap into the electric wiper wire. You will need a special"Y" connector if you already have electric wipers. Do yourself a favor and do not butcher the harness with boat connectors as I have seen done so often, the end result will be bad down the road. A lot depends on how you want to hook it up, if you still have the safety switch on the motor then you cab recreate the entire #77 circuit and that way you have all of the protection of the breaker and the rollover protection to shut the pump off. There is no "on/off" switch per say. Just the ignition and the oil pressure safety switch in the stock setup.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Re: New front harness, flat batteries

Unread post by TraceL » July 23rd, 2018, 2:12 pm

The pump does work. I wanted to get away from it because I knew the a2 harness wasn’t set up for it. That, and the electric pumps are ridiculously expensive if I ever needed to replace it. The Jeep ran fine with the electric pump setup before I replaced the harness and switched it over to mechanical. I have to believe it’s issue is related to the fuel delivery. I’m also going to see if I can find a third coil to test, just so I can cross that off the list. The symptoms are very similar to a bad coil issue, but changing it to a “assumed” good one didn’t make any difference. I let the Jeep idol for about 25 minutes and it never stuttered. As soon as I took it up to about 40 mph, it started to buck until I depressed the clutch. Then it just stalled after about 30 seconds. It stalled like a motor running out of gas.
1962 M151

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Re: New front harness, flat batteries

Unread post by TraceL » July 24th, 2018, 7:27 pm

Does anyone know the best way to post pictures in these technical discussion forms? I will like to put up a few pictures and get the groups opinions on the carburetor setup.
1962 M151

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