How do you test the RPM of 12 HP B&S engine riding mower? I believe I may have the tools to do it but I don't know what to hook up to where on the engine.
Any help would be appreciated.

You should be able to use a tack that attaches to the spark plug wire with an inductive pickup.

You would just have to adjust for the number of cylinders. Use say 4 CYL and divide by 4.

There are special tachs and testers for small engine repair.

Quote:

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Originally Posted by KeepItSimpleStupid

You should be able to use a tack that attaches to the spark plug wire with an inductive pickup.

You would just have to adjust for the number of cylinders. Use say 4 CYL and divide by 4.

There are special tachs and testers for small engine repair.

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I only have a tack meter with two leads (no inductive pickup) . What do I hook them up to?
Any other solutions?

I do appreciate your help.

Tecumseh - Vibra Tach / Tachometer 670156

About $40

Lawn Mower Parts

And

ESI 321 Versa-Tach Digital Small Engine Tachometer

If your engine has points, you should be able to get a regular tack to work with a 9V battery and a couple of diodes. I'm assuming it doesn't. If it has points, we can explore that option.

Quote:

---

Originally Posted by KeepItSimpleStupid

Tecumseh - Vibra Tach / Tachometer 670156

about $40

Lawn Mower Parts

and

ESI 321 Versa-Tach Digital Small Engine Tachometer

If your engine has points, you should be able to get a regular tack to work with a 9V battery and a couple of diodes. I'm assuming it doesn't. If it has points, we can explore that option.

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** It does not have points. It has a solenoid , starter, ammeter,and a bunch of safety switches.
I appreciate your patience with my lack of knowledge in this area but this is how we learn.
I thank you for your help.