Still not correct.
The capacitor on pin2 is installed incorrectly.

 

I turned it around. Led is still on

 

What does that mean "turned it around"?

 

I assumed you meant the polarity was wrong g

 

I assumed you meant the polarity was wrong g

There's no polarity on that cap.
Post a current photo of the breadboard please.

 

 

You have pin2 of the 2907 connected to ground and the cap which should connect from pin2 to ground is shorted out by the breadboard.
Remember all the vertical receptacles or holes are connected together.
Make sure the negative leg of the 1uf cap also connects to ground.

 

Yep I see that now.I'll make a change.I appreciate you sticking with me on this

 

Here's my latest try

 

The red wire should be moved one place to the left because
the red wire is shown connected to the green wire.
Rest looks OK but don't really need all those white wires.

 

Ok.I hooked it back up and the led stayed out,I revved it to 5k rpm

 

Did you apply power to the circuit as shown wired in post#69?
If so the chip is damaged.

 

Ok I have several just in case

 

Show another current photo of the wiring on the breadboard please.

 

 

Everything looks OK.
A quick test to check the 2907 is to connect a jumper from pin2 to ground but don't change or remove any other components.
Connect power only and see if the LED lights up.
If that works then I would say the chip is probably OK otherwise try another chip.
Another issue is the actual number of pulses that are generated on a single rotation of the shaft.
I calculated the 120K resistor value on 1 pulse per rotation but it could be 2 or more.
Do have a meter that can measure frequency?

 

I just notice that the wires on the LED are reversed if black is the negative leg.
This might be the only problem.

 

I grounded pin 2 and the led worked.I also switched the led leads.I don't have a frequency meter

 

OK then give it another try with the tach connected.
Do you have a multimeter?

 

I do have a multi meter. The led was flickering as the engine turned over when it started the led turned on