tac question

mobgod

mobgod

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Going crazy I did read my book told me to hook my grey wire to sender but the tac is stuck at 5000 rpm does that mean it's no good help plz
 
B

boobie

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Re: tac question

Have you got the tach hooked up with B+ voltage from your ign sw and a good ground ??
 
mobgod

mobgod

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Re: tac question

boobie said:
Have you got the tach hooked up with B+ voltage from your ign sw and a good ground ??
Click to expand...
what do you mean B + voltage I got direct power in did l to lights s is for the grey wire g is ground and i should be my purple wire is there a way I can test the tach to make sure it's not bad I have it set to five but the needle is on 50 5000 so not sure if it's broke
 
Joe Reeves

Joe Reeves

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Re: tac question

mobgod said:
what do you mean B + voltage I got direct power in did l to lights s is for the grey wire g is ground and i should be my purple wire is there a way I can test the tach to make sure it's not bad I have it set to five but the needle is on 50 5000 so not sure if it's broke
Click to expand...

I can't tell where any of that starts or ends. Use some periods, commas etc in your explanations so that we know what you're speaking of. If you have a tachometer with a dial and four wires leading from it. The color of the wires should be Blue, Black, Purple, and Gray.

The dial should be set to #6.
Blue wire supplies voltage to the light bulb in the tachometer.... connect that wire to the proper terminal of the light switch.
Black wire connects to a known ground. DO NOT connect this wire to either "M" terminal of the ignition switch!
Purple wire (+ voltage) connects to the "A" terminal of the ignition switch.
Gray wire connects to the Gray wire (sensor) leading from the engine/instrument wiring harness.

If all is well, the tach should drop to zero when you turn the key to the ON positiion.
 
mobgod

mobgod

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Re: tac question

Joe Reeves said:
I can't tell where any of that starts or ends. Use some periods, commas etc in your explanations so that we know what you're speaking of. If you have a tachometer with a dial and four wires leading from it. The color of the wires should be Blue, Black, Purple, and Gray.

The dial should be set to #6.
Blue wire supplies voltage to the light bulb in the tachometer.... connect that wire to the proper terminal of the light switch.
Black wire connects to a known ground. DO NOT connect this wire to either "M" terminal of the ignition switch!
Purple wire (+ voltage) connects to the "A" terminal of the ignition switch.
Gray wire connects to the Gray wire (sensor) leading from the engine/instrument wiring harness.

If all is well, the tach should drop to zero when you turn the key to the ON positiion.
Click to expand...
Sorry Joe using my phone it's a pain in the ***. Now for the dial the one I have only goes to five .Joe for the next part can you explain the A and M plz so I can get this wired correctly
 
mobgod

mobgod

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Re: tac question

mobgod said:
Sorry Joe using my phone it's a pain in the ***. Now for the dial the one I have only goes to five .Joe for the next part can you explain the A and M plz so I can get this wired correctly
Click to expand...
OK edit I got the A and M now A is purple and M is black, so your telling me not to use the M for my ground correct. The other part my tech only goes to five is that OK or do I need a different one?
 
Joe Reeves

Joe Reeves

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Re: tac question

mobgod said:
OK edit I got the A and M now A is purple and M is black, so your telling me not to use the M for my ground correct. The other part my tech only goes to five is that OK or do I need a different one?
Click to expand...

I'm not familiar with any tach that only goes to number 5 on its dial so I'll let some other member jump in here to answer that question.

The "A" on the back of the ignition switch stands for "Accessory" which has 12 volts applied to it ONLY when the key is turned to ON or START.... so this is where you would want the tach power supply hooked up to.

And you are correct... DO NOT use either of the "M" (Magneto) terminals of the ignition switch for ground purposes. Reason is... Any component that has voltage applied to it has voltage flowing thru it internally, then that voltage flows out of it via its ground wire to the negative terminal of the battery. If you connect that ground wire to either "M" terminal of the ignition switch, you will have that voltage also flowing towards a powerpack, ignition points, condensers, whatever ignition setup the engine might have... the result being in a very short time a damaged ignition system.

Bottom line... If one does not know of a absolute ground running to the negative terminal of the battery, run a separate black wire and create one to be on the safe side..
 
mobgod

mobgod

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Re: tac question

Joe would it be easier if i took a picture of the tach and send it to you or the model number ?
Joe Reeves said:
I'm not familiar with any tach that only goes to number 5 on its dial so I'll let some other member jump in here to answer that question.

The "A" on the back of the ignition switch stands for "Accessory" which has 12 volts applied to it ONLY when the key is turned to ON or START.... so this is where you would want the tach power supply hooked up to.

And you are correct... DO NOT use either of the "M" (Magneto) terminals of the ignition switch for ground purposes. Reason is... Any component that has voltage applied to it has voltage flowing thru it internally, then that voltage flows out of it via its ground wire to the negative terminal of the battery. If you connect that ground wire to either "M" terminal of the ignition switch, you will have that voltage also flowing towards a powerpack, ignition points, condensers, whatever ignition setup the engine might have... the result being in a very short time a damaged ignition system.

Bottom line... If one does not know of a absolute ground running to the negative terminal of the battery, run a separate black wire and create one to be on the safe side..
Click to expand...
 
Joe Reeves

Joe Reeves

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Re: tac question

A picture, front & back would help. Possibly I might have no knowledge of it but someone here would I'm sure.
 
mobgod

mobgod

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Re: tac question

Joe Camera is not working but that is the model number if you can help me out
 
Joe Reeves

Joe Reeves

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Re: tac question

Sorry, I cannot BUT hopefully some other member will jump in here with the proper knowledge.
 
mobgod

mobgod

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Re: tac question

Hi Joe this is what i did today, I hooked the ground wire direct to a battery turned the key on the gauge is still at 50 (5000) could that be a sign that the gauge is no good ? Also anything else i can try or should i just buy a gauge and end it, if so what gauge plz
 
Joe Reeves

Joe Reeves

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Re: tac question

Sorry, I'm not familiar with that tachometer and have been hoping that someone would jump in here who is.

I don't believe that you've mentioned what engine you have. Model number?
 
mobgod

mobgod

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Re: tac question

I did it's a Johnson 200TXL77C
Joe Reeves said:
Sorry, I'm not familiar with that tachometer and have been hoping that someone would jump in here who is.

I don't believe that you've mentioned what engine you have. Model number?
Click to expand...
 
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