master off/on switch

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Lindsay36551
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master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 1:49 pm

I am restoring an A1, I finally got it running today!
When I went to turn it off , the engine kept running!
Every thing else, gauges all shut down.
Any thoughts?
Best regards
Lindsay
1967 M-35-a2-D SOLD
1973 M151A2
M151 A1-SOLD
196? franken MUTT
M1oo trailer-sold
1963 M151-sold
1968 M416 trailer
1988 998 Humvee-4 man
1994 998 Humvee-up armored

Hambone
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Re: master off/on switch

Unread post by Hambone » May 19th, 2018, 2:06 pm

The #12 wire of the master switch powers the distributor, is the power being killed on that leg when you turn the switch off? the master switch has two contacts.
Is it wired correct? Here is some notes I dug up a while back, this is looking at the back of the switch.
Image

Fil Bonica
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Re: master off/on switch

Unread post by Fil Bonica » May 19th, 2018, 4:10 pm

Did you break positive or negative line?

Fil Bonica
K1ABW

Lindsay36551
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Re: master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 5:06 pm

Fil, I'm not sure.
I will check tomorrow!
Also the engine is running like crap! gotta figure that out next!
Engine ran perfect before restoration! didn't change anything .
1967 M-35-a2-D SOLD
1973 M151A2
M151 A1-SOLD
196? franken MUTT
M1oo trailer-sold
1963 M151-sold
1968 M416 trailer
1988 998 Humvee-4 man
1994 998 Humvee-up armored

Mark
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Re: master off/on switch

Unread post by Mark » May 19th, 2018, 5:09 pm

bad gas/water?
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

Lindsay36551
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Location: eustis fl

Re: master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 5:25 pm

Brand new, NON ethanol fuel!
1967 M-35-a2-D SOLD
1973 M151A2
M151 A1-SOLD
196? franken MUTT
M1oo trailer-sold
1963 M151-sold
1968 M416 trailer
1988 998 Humvee-4 man
1994 998 Humvee-up armored

Lindsay36551
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Posts: 911
Joined: December 19th, 2011, 12:31 pm
Location: eustis fl

Re: master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 6:14 pm

Ok, switch has 2 ridged sockets, Both #11 wires have ridges on plugs.
put #27 in one and #12 in the other, No joy!
Tried every combo I can think of still no result!
Also installed a ground wire from engine to body still nothing!
1967 M-35-a2-D SOLD
1973 M151A2
M151 A1-SOLD
196? franken MUTT
M1oo trailer-sold
1963 M151-sold
1968 M416 trailer
1988 998 Humvee-4 man
1994 998 Humvee-up armored

Hambone
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Re: master off/on switch

Unread post by Hambone » May 19th, 2018, 6:27 pm

Looking at the back of the switch in the mounted position, the #11 wires go in the LH upper and lower socket, the #12 wire goes in the RH upper socket and the #27 goes in the RH lower socket, is that how you have it wired?

Lindsay36551
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Re: master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 6:37 pm

Yes, Sir!
1967 M-35-a2-D SOLD
1973 M151A2
M151 A1-SOLD
196? franken MUTT
M1oo trailer-sold
1963 M151-sold
1968 M416 trailer
1988 998 Humvee-4 man
1994 998 Humvee-up armored

Hambone
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Re: master off/on switch

Unread post by Hambone » May 19th, 2018, 7:08 pm

Pull the wire off the distributor and check voltage there or you can check #12 terminal on switch, if you have power there with the switch off, could be bad switch, if you have continuous power to the distributor, disconnect the battery.

Lindsay36551
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Re: master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 7:18 pm

I do have a master control switch for battery's, if I had this on the power side of things would that cause this problem?

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rickf
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Re: master off/on switch

Unread post by rickf » May 19th, 2018, 8:54 pm

Is this an A1? If so is the oil pressure safety switch wired correctly? If not when you get oil pressure you could backfeed the coil wire. I have seen this before but I don't remember the wire right off. I need some sleep and an xray in a broken hand. I will look into it tomorrow if you have not figured it out.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Hambone
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Re: master off/on switch

Unread post by Hambone » May 19th, 2018, 9:38 pm

I don't have an A1 wiring diagram in front of me but I think that is #77 circuit, goes from circuit breaker to safety switch, then to fuel pump, could be wrong tho.

Lindsay36551
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Re: master off/on switch

Unread post by Lindsay36551 » May 19th, 2018, 11:02 pm

Rick, oil pressure switch is # 36,
After thinking this through tonight, I think I have a bad switch!.
Worked fine yesterday.
This was the original switch that came with the 151. probably just as well to change it out!
We definitely have the old guard on board for this thread!
Welcome aboard! Its :D :D :D :D :D :D great to hear from all of you!!!!
1967 M-35-a2-D SOLD
1973 M151A2
M151 A1-SOLD
196? franken MUTT
M1oo trailer-sold
1963 M151-sold
1968 M416 trailer
1988 998 Humvee-4 man
1994 998 Humvee-up armored

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rickf
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Re: master off/on switch

Unread post by rickf » May 20th, 2018, 11:33 am

Those switches seem to be a common failure item. I have not had any totally fail but I did have one that I had to play with to get it to work every time.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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