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4bt tach?

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New problem--oil leaking from turbo

cummins 4bt mileage in an m715

how can i run a tach on my 4bt? my alt is new, and does NOT have a tach output. its a cpl0858 from frito lay and i need to know if there is an easy way... .



also if i am not, and dont believe i can, run an intercooler, can i run a 12cm housing?
 
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I have an Isspro tach that simply runs off the alternator. It does not use the sensor kit.

I had to remove the back cover of the alternator and connect a wire to one of the rectifyer leads.

It then had to be calibrated with a hand held optical tach.

Tach works good. Just another option.

Jay
 
Auto Meter makes a diesel tach that mounts a sensor on the outside of the alternator. It does require calibration after install.

I plan to order one this week for my 4bta in my 1943 Dodge Carryall. Sorry, I am on the road and dont have the model number with me. The price is very reasonable.



WM-300
 
The magnetic sensor bolts onto the timing cover in the same way the stock one does on the later years. The sensor is set with an air gap so that the magnets pass by close enough to trigger a pulse.



A 4 cylinder tach requires two magnets and V8s need 4. It's very accurate and won't require calibration.
 
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