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Discussion Starter #1
Well I'm starting in on my 4BTA and was wondering what the 3 pin sensor/ connection is that is mounted on the bottom of the intake manifold. it's underneath and kind of recessed (oval shaped).
 

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Well I'm starting in on my 4BTA and was wondering what the 3 pin sensor/ connection is that is mounted on the bottom of the intake manifold. it's underneath and kind of recessed (oval shaped).
You are most likly refering to the KSB Sensor. Two types of KSB actuaction has been used, and both require different senors.

Wax Motor KSB CUmmins Part Number 3915945
The sensor (switch) is located in the water jacket and measures coolant temperature. The Sensor (switch) is Normally Open. When coolant reaches 160 Degrees F, the sensor (switch) closes and 12 volt power is applied to the Wax Motor which allows timing to return to normal

Solenoid Type Cummins Part Number 39221642
The sensor (switch) is located in the intake manifold and measures air temperature. The sensor (switch) is a normally closed which allows 12 volts to activate the solenoid and advance the timing. When the air temp in the intake manifold reaches 90 degrees F, the sensor (switch) opens and allows the solenoid to relax thus allowing the timing to return to normal. Some CPL's use a 3 ohm resistor in the solenoid power line. I dont know why, nor does the shop manual describe the resistors use on certain CPL's

The sensors (switches) are not interchangable

On my engines, I have the wax motor type. I bypass the sensor(switch) and run power to the Wax motor all the time. Thus I never see the timing advance on a cold engine. I dont see and white smoke which the elimination of it was the purpose of the KSB.

Paul
 

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I would guess that is the air temp sensor for the KSB (cold start device).

On the 6BT there are only three sensors that I know of, the above mentioned temp sensor (near fuel filter block), the coolant temp sensor (back of the head) and the oil pressure sensor.
 

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If it was equipped with an electric fan there's also a fan sensor/switch located down in the lower radiator hose outlet, and under the turbo you may find another plugin for the factory installed block heater.
 

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Discussion Starter #6 (Edited)
CJ8: That is indeed the location and appearence of what I'm refering to.
Paul: "KSB" & "WAX MOTOR" are beyond my scope. I got an idea of what they are by the follow-on posts...any other references so I can learn more about that aspect of the engine? There are only 3 sensors I can find, one on the thermostat housing top front passenger side (H20 temp.), another mid-driver side of the block (oil press. I believe) and the third as described in the thread subject.....any others? Thanks guys
 

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CJ8: That is indeed the location and appearence of what I'm refering to.
Paul: "KSB" & "WAX MOTOR" are beyond my scope. I got an idea of what they are by the follow-on posts...any other references so I can learn more about that aspect of the engine? There are only 3 sensors I can find, one on the thermostat housing top front passenger side (H20 temp.), another mid-driver side of the block (oil press. I believe) and the third as described in the thread subject.....any others? Thanks guys
Treetopflyer;
The KSB has been discussed here before. Do a search to save me typing. IF you cant find it, I will post again. Thanks, saves my fat fingers pounding on the keys ha ha. The only source I know of for KSB info is the Cummins Shop Manual.

Paul
 

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Treetopflyer;
The KSB has been discussed here before. Do a search to save me typing. IF you cant find it, I will post again. Thanks, saves my fat fingers pounding on the keys ha ha. The only source I know of for KSB info is the Cummins Shop Manual.

Paul
I uploaded the KSB info to my Image Event Site. Go to the link and double click on each picture for a full screen. You can also right click and save and blow up even larger on your onw computer. This is from the Cummins Shop Manual.
http://imageevent.com/moosecreekmaple/cumminsksb

Paul
 
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