Different Tachometer Location

[NOberdier]

I have been looking through the archives and it seems that most people run there tachs off the alternator or use a pickup on the flywheel. I am a mechanic in the Army and a lot of our vehicles use Cummins of various sizes including some 6BTs. All of them use a tach running off the injection pump nut. There is a piece the slips over the IP nut and goes through a bearing piece that mounts where the civilian 6bts mount their oil fills. Then an electronic pickup is attached and wired into the tach gage. Just wondering if anybody has seen this setup on a Dodge truck Cummins??

 

[dpuckett]

I've never seen it in a Dodge, but have seen it in some ag ans industrial applications. You would have to get a valv ecover with a fill hole in it, though. Not for those in a hurry, from what I hear.



Daniel

 

[JLEONARD]

 Not for those in a hurry, from what I hear

I had this type on my marine 6BTA. Really didn't make things much different or take any appreciable time compared to the truck style tube. A properly sized funnel would even things up.



Jay

 

[Greenleaf]

I have not seen that. It seems to be popular to use the alternator on the early trucks (some vehicle use this from the factory, like a school bus w/Cummins) and use the supplied pick-up and harness for the later 1st gen trucks.



The valve cover fill is used on the school bus engines, so they are available. You cannot pour a gallon of oil down into that hole all at once. It's better to use quart bottles or a bulk air pump set on ultra slow mo.

 

[sdstriper]

Tach Drive P/N's

I have some part numbers for the tach drive off the Fuel Pump gear nut. The parts it takes to do this are approx. $200 and then you need a tachometer too! Unless you can find the Angle Drive Adapter somewhere cheap, then it may be worthwhile.



Hub, tach drive coupling 3905306

Seal 3903475

Adapter, tach takeoff drive 3918215

Seal 3915800

Adapter, angle drive 3905217 $127. 68! Stewart-Warner has one of these, looks close, approx. 80. 00 bucks.





You would need the oil fill valve cover too. For under $30 you can get one with the fill cap and seal from Cummins.