Got a Cummins B series diesel but no tach? Surprisingly, lots of these B Series came out of the factory in truck and industrial applications without tachometers. We think that running a diesel without a tachometer is like driving at night without headlights. Sure, you can do it, but why? So if you have a Cummins B series without a tachometer and want to add one, here’s the skinny:
Parts List
First, pick up the following Cummins parts:
| Description | Part No. | |
| Tach Drive | DF 9013 | |
| Valve Cover, 6 Cylinder | 3902605 | |
| Valve Cover Gasket | 3902666 | |
| Filler Cap | 3901895 | |
| Seal Ring | 3902363 |
From a Stewart Warner dealer, you’ll need:
| Tach, 3500 RPM | 9CWB994C | |
| Drive Tang | B821870 | |
| Tach Sender | 9CWB106AW |
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.
We hope this was helpful. At Foley Engines we are different; we want to help!
