Helpful guide on installing a tachometer in your Cummins B series Diesel
Got a Cummins B series diesel but no tach? Surprisingly, lots of these B Series come out of the factory in truck and industrial applications without tachs. Our Dr. Diesel™ says that running a diesel without a tachometer is like driving at night without headlights. Sure, you can do it, but why? So here’s the skinny:
First, pick up the following parts from Cummins:
|Tach Drive||DF 9013|
|Valve Cover, 6 Cylinder||3902605|
|Valve Cover Gasket||3902666|
From a Stewart Warner dealer, you’ll need:
|Tach, 3500 RPM||9CWB994C|
From a speedometer shop, buy a standard speedo cable with .104 drive ends.
Installing Your Tach
Remove the oil filler tube assembly and install the plastic drive unit on the now exposed nut in the gear cover. Install the new valve cover, gasket, filler cap, and seal ring in place of the old filler hole-less valve cover. Hook the speedo drive cable to the drive and the tach sender unit (which can be mounted anywhere). Hook the wiring up between the sending unit and the tack, remembering always that the drive ratio is 0.5:1.
Please call with any questions. We stock Cummins B Series Service Manuals and supply them free of charge with our B Series engine overhaul kits.