Installing a Tachometer

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Nick_
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Installing a Tachometer

Unread post by Nick_ » June 11th, 2017, 11:50 pm

As my vehicle will be mainly used off-road, I believe an hour meter would best display drive time. Also when fording in the water - an rpm gauge to ensure I'm not putting too much stress with closed crankcase vents.

The M35A2 has a perfect tach/rpm gauge (and looks good), but then I found it uses a cable system. Has anyone successfully installed a tach off the coil? Any vintage gauge suggestions?

Humvee tach looks cool but unsure if it can be set to 4 cylinder.

Husker
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Re: Installing a Tachometer

Unread post by Husker » June 12th, 2017, 8:49 am

I bought an m35 gauge cluster to try and do it I feel like the m35 tach would work but I wanted to run both and need to find either the electronic setup or the splitter for the speedo cable
US Army Fort Belvoir

19XX M35 something. Sold......
1972 M151A2
1967 M416
On the hunt for an M1031

Nick_
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Re: Installing a Tachometer

Unread post by Nick_ » June 28th, 2017, 11:45 pm

Bump to see if anyone new reading the post has any experience with this.

The difficult part I foreshadow is the lack of ground wire coming out of the distributor as the coil is not mounted outside. Could I run a ground wire out of the distributor anywhere?

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rickf
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Re: Installing a Tachometer

Unread post by rickf » June 29th, 2017, 3:42 pm

Only by drilling a hole for the wire and putting in a tight fitting grommet. Are you relocating the ground for the wire. What are you grounding? The coil is not grounded to to the case, the negative of the coil goes to the points or electronic ignition module and those in turn are grounded through their mounts to the body of the distributor. If you ground the coil you will have no spark.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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svramselaar
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Re: Installing a Tachometer

Unread post by svramselaar » June 30th, 2017, 2:14 am

hi

rickf
i think he must have the negative side wire from the coil for the pulse to the tacho
i use it for the LPG safety relays so the engine gets only LPG as there is a spark

george

Fil Bonica
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Re: Installing a Tachometer

Unread post by Fil Bonica » June 30th, 2017, 9:43 am

There is an adaptor in the kit for electrical testing specifically for that purpose.
Give me your email and will send a pic

Fil Bonica
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rickf
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Re: Installing a Tachometer

Unread post by rickf » June 30th, 2017, 9:52 am

Nick_ wrote:As my vehicle will be mainly used off-road, I believe an hour meter would best display drive time. Also when fording in the water - an rpm gauge to ensure I'm not putting too much stress with closed crankcase vents.

The M35A2 has a perfect tach/rpm gauge (and looks good), but then I found it uses a cable system. Has anyone successfully installed a tach off the coil? Any vintage gauge suggestions?

Humvee tach looks cool but unsure if it can be set to 4 cylinder.
The Humvee tach will be run off of the alternator since it is a diesel. The adapter that Fil is proposing is a possibility if you seal it good but you are still dealing with 24 volts.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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