electric tach for vac

[kenbob]

I was thinking of buying an electric tach for my vac. It is still 6v pos. There are all kinds of cheap tachs out there. Has anyone used one?
Since they are battery powered it would seem the 6v pos wouldn't make a difference, but I would like to know if that is not true. Thanks.
 

[Dingo3]

You cant use a 12v tach on 6v without a converter of some type.
Look up Westach, they have them. Dont know how good they are, Ive never used one.
 

[kenbob]

The ones I was considering were digital and operated with their own battery as power source. One wire that wrapped around the outside of a sparkplug wire as a sensor.
 

[Dingo3]

That would work. Does it need a source for the light?
 

[kenbob]

No, it supposedly picks up the vibration thru the sparkplug wire. What I can't figure out so far from the online ads if they can be used on a 4 cyl tractor. They are mostly for single or twins. I suppose if it reads the pulses you could figure out rpms
 

[Al nickel]

What is the value of a tach on a Case Vac??

Maybe , just let the idea go ??
 

[kenbob]

For 13 dollars I have ordered one. Mainly for tuning purposes as I have no idea if the tractor is set and running at the normal rpms. Something isn't quite right with it. I found one you set for number of cylinders and you can set it serves as a resettable hour meter as well. Mostly i need a new toy I guess. I will post after I get it to see if it is worth the $13
 

[kenbob]

Actually I ended up paying $22 for one with lifetime warranty and made in Tiawan instead of China.
 

[DKase]

one cyl, or 16 cyl makes no difference. spark fires once every 2 turns on a spark plug wire.
 

[kenbob]

Thanks