Digital tach

[cooter2506]

I have a digital tach for getting rpm of blower wheels for HVAC units. You put a silver piece of tape on one of the fins and run blower and it gives you a read out while poiting at wheel. My question is can this be used on my 1998 5.0 merc? If so where would give e the best reading so I can check my in dash tach. Thanks in advance

 

[Bondo]

Re: Digital tach

If so where would give e the best reading

Ayuh,... The Crankshaft Pulleys...

 

[Zackman]

Re: Digital tach

Yep, crankshaft harmonic balancer hub/pulley. All the others pulleys are likely rotating at a different speed.​