New front harness, flat batteries

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rickf
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Re: New front harness, flat batteries

Unread post by rickf » July 18th, 2018, 12:59 pm

Mark wrote:Instead of dielectric grease for the plug connections I used lucas green wheel bearing grease
Dielectric grease is silicone and will not affect the rubber of the connector. Wheel bearing grease is petroleum based and will soften and destroy rubber.
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 rickf » July 18th, 2018, 1:03 pm

Fil Bonica wrote:It is more important to refer to an A2 harness rather than just an A1.
You need to reference both to make the proper adjustment from one to another:
Especially for lighting differences and the whole electrical fuel pump wiring if he is still using it.
This may be moot if he is using a mechanical pump.
Just some obvious things that come to mind.

Fil Bonica
If you look at that diagram you will notice that it has all of the A1 lighting AND the A1 #77 circuit for the fuel pump BUT it has the 60 amp and optional 100 amp charging systems of the A2. He is working with an A1 with a 60 amp charging system so this diagram should be spot on.
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 18th, 2018, 1:18 pm

Very light sparking now with the alternator hooked up. Instead of the 26 volt reading I was getting before. I now have a -24 volt reading. Starting to to think the alternator is the problem?
1962 M151

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Re: New front harness, flat batteries

Unread post by rickf » July 18th, 2018, 1:35 pm

You can get a voltage reading with only a miliamp draw which will not kill the batteries. You really need a 24 volt incandescent test light that you can easily make from a spare bulb. I did not want to get back into the conversation because there are several people here taking you in several directions and that is just not going to work. I specialized in electrical diagnosis for 40 years. You have to have a dedicated path of diagnosis and follow that path only from start to finish. I advise on 6 forums so I cannot be competing to be the guy who won the prize for getting it right. Solder a wire on the side of a bulb and another wire to the bottom post on the bulb and use that as your tester. If the bulb lights then there is enough draw to kill the batteries. Now pick one person and follow their lead.

PM me if you need my help but I will not compete.
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 Fil Bonica » July 18th, 2018, 2:00 pm

I mispoke when I said the harness was not powered.
It is by virtue of it being connected at the starter switch by number 5.
Connecting at the alternator could reveal a leakage path through a defective regulator.
Rick, its all yours!

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Re: New front harness, flat batteries

Unread post by Fil Bonica » July 18th, 2018, 2:30 pm

With my A2 in front of me I tried some testing.
With engine off I measured voltage at the 5 on the alternator.
26. Volts. On an analog meter
Disconnected number 5 and measured the same voltage between 5 and open terminal.
Performed same test with a test light,
No light.
With the engine running voltage rose to 28.5 and was stable.indicating that the system was charging.
See how those findings compare to what you see.

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Re: New front harness, flat batteries

Unread post by Fil Bonica » July 18th, 2018, 2:30 pm

With my A2 in front of me I tried some testing.
With engine off I measured voltage at the 5 on the alternator.
26. Volts. On an analog meter
Disconnected number 5 and measured the same voltage between 5 and open terminal.
Performed same test with a test light,
No light.
With the engine running voltage rose to 28.5 and was stable.indicating that the system was charging.
See how those findings compare to what you see.

Fil Bonica
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Re: New front harness, flat batteries

Unread post by Fil Bonica » July 18th, 2018, 2:30 pm

With my A2 in front of me I tried some testing.
With engine off I measured voltage at the 5 on the alternator.
26. Volts. On an analog meter
Disconnected number 5 and measured the same voltage between 5 and open terminal.
Performed same test with a test light,
No light.
With the engine running voltage rose to 28.5 and was stable.indicating that the system was charging.
See how those findings compare to what you see.

Fil Bonica
K1ABW

Mark
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Re: New front harness, flat batteries

Unread post by Mark » July 18th, 2018, 2:52 pm

Rickf thanks for the feedback, am I remembering right in using dielectric grease for the cam lobe in the distributor for the points back in the 1970's?
I may stand corrected I found niehoff nl-2 distributor cam lubricant, but also found dielectric tune-up grease from permatex
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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Re: New front harness, flat batteries

Unread post by TraceL » July 18th, 2018, 5:40 pm

So I have some good news. After disconnecting and reconnecting everything, I appear to have solved a few issues. I swapped out the voltage regulator on the alternator and that appears to have cured the headlight and gauge pulsating. I ended up with a bad circuit breaker due to my own installation error. I had a #27 & #25 hooked to each breaker instead of the two #25 to one and the two 27’s to the other breaker. I don’t want to jinx it but the electrical issues seem to have gone away. The only problem is that out on my test drive, after driving for about 15 minutes, the engine wanted to crap out if I went over 30 mph or really stepped on the accelerator. It was really low on fuel so I topped it off, but it didn’t seem to solve it. I switched it over to the mechanical fuel pump shortly before I put the new harness in. I apologize that my mutt and I are being a pain. I really appreciate the insight from you guys.
1962 M151

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Re: New front harness, flat batteries

Unread post by TraceL » July 18th, 2018, 7:04 pm

The new issue definitely happens once the engine is warmed up. Changed the carburetor so it isn’t that. Fuel filter just before the inlet is 99% full so it doesn’t seem to be lack of fuel. Vapor lock of some sort? I haven’t sourced a military fuel pump yet so I have a civilian one without the vent.
1962 M151

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Re: New front harness, flat batteries

Unread post by Fil Bonica » July 18th, 2018, 8:04 pm

The Airtex pump has been flawless over the years.
The vent line is only for running the engine submerged.
A military pump is now getting very expensive.the repo ones are a bit problematic also.
you may want to look a little closer at things before you make a swap.
Then and Now in Weymouth will rebuild and old gi pump if you decide to go that way.
If I were you I would look at clogged fuel filter or filters before anything else.Just because they are new doesn’t mean they are good.
Good luck.

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Re: New front harness, flat batteries

Unread post by rickf » July 18th, 2018, 8:58 pm

Don't forget the filter in the tank. T in a vacuum gauge in the fuel line before the mechanical pump and see if you are drawing a vacuum on the fuel line. If you are then the filter in the tank is clogged. make sure the gas cap valve is open.
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 Hambone » July 18th, 2018, 9:39 pm

Not to say it isn't the fuel, but the coil could come into play, when my coil failed, it would run great until the engine warmed up, then it would miss like crazy.

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Re: New front harness, flat batteries

Unread post by TraceL » July 18th, 2018, 10:48 pm

Thanks. I will try each of these suggestions. The setup I'm currently running for fuel filters is; filter at the beginning of the feed line in the tank, then a civilian WIX clear plastic filter after the fuel pump which feeds right into the military fuel pump attached to the carburetor. The Clear filter is filled 100% with fuel. I thought I recalled it only being 2/3 to 3/4 full while running before this issue. I am wondering if the military fuel filter after the civilian one is clogged. If so, can I just eliminate it? Does the system need the back to back filters? I only did this setup, because thats what I had seen others run in pictures online. Rick, I hope this isn't a dumb question, but how do you open the valve on the gas cap? I recently put a new cap on it because my old one leaked when taking right turns.
1962 M151

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