Df140 tac question!!!!!!!

[bigbluetundra]

Hey my rpm tachometer for my df140 goes crazy... it will go to maybe 2500 rpm the just start jumping around then stops working... do you guys think it the tac?? Or something else

[Solarman]

Should be a switch on the back, maybe covered by a rubber plug (not sure if talking analog, or digital?), try switching back and forth a few times, ending where it originally was. Sometimes those contacts get dirty. See if that helps.
Might help more if you indicated what year motor & gauges you have.

Good luck.

[artdf175]

while you are at it check the wire connections
almost sounds like a loose connection or broken wire
re the input from Solarman.. I had that problem a few years ago
just kind of indicated a RPM that was jumping around and reading funny numbers. moving the lever on the back that goes between different modes cleaned the internal contacts, however it never just stopped working.
art

[bigbluetundra]

Should be a switch on the back, maybe covered by a rubber plug (not sure if talking analog, or digital?), try switching back and forth a few times, ending where it originally was. Sometimes those contacts get dirty. See if that helps.
Might help more if you indicated what year motor & gauges you have.

Good luck.

Motors are 2004 johnson/Suzuki 140... where is the switch on the back located at.. do I need to pull engine crown off?? The gauge is a faria gauge thanks

[artdf175]

on the back of the tac itself..

can have a plug over the hole or just a small slider
art

[bigbluetundra]

while you are at it check the wire connections
almost sounds like a loose connection or broken wire
re the input from Solarman.. I had that problem a few years ago
just kind of indicated a RPM that was jumping around and reading funny numbers. moving the lever on the back that goes between different modes cleaned the internal contacts, however it never just stopped working.
art

What level are u talking about?? How can I find the level?

[artdf175]

Electronic tachometers work by counting pulses generated by the ingition system, alternator, tach signal generator or magnetic pickup sender. The tach is hooked up to +12vDC, Ground and one of hte signal sources listed above.

By selecting the right tach and setting the switch on the back to the correct postion you let the tachometer know how many pulses are sent per each engine revolution.

look for a "switch" on the back of the tach\

[bigbluetundra]

on the back of the tac itself..

can have a plug over the hole or just a small slider
art

Just went to look.... looks like there is a black little turn key... with numbers 5 and 6 ... do I need to take that price off or just turn that piece a few times ?? Also if I do this and the problem is still there what would be the next step to look for

[artdf175]

yes would turn the switch several times to see if that is the problem
if not with it cutting out on you completely next think I would do would be to check wiring connectors
can you tell what model number it is?
web site
Manuals and Documents

Art

[bigbluetundra]

yes would turn the switch several times to see if that is the problem
if not with it cutting out on you completely next think I would do would be to check wiring connectors
can you tell what model number it is?
web site
Manuals and Documents

Art

All I can find unless I pull the tac off is a number cs0457e

[artdf175]

I did some searching for more info at the manufacturers web site and do not see anything with that model number
There were several manuals
Is this a digital tach or analog ?
The analog ones I see should have 3 setting a 4 , 6 or 12
Again though from what you had for symptoms before I would go buy a new gauge I would go through the wiring
Take apart connectors and put back together
If you have a manual you might be able to track the wiring via the harnesses

[artdf175]

One other thought check the ground wires
Bad grounding creates havoc with electronics