You're kidding?! So it'll be hot all the time except when it's cold? What triggers the voltage when warm? This changes things...
g

 

btw, thanks fot the info, torquefan

 

Greg

I just did a little test driving home from work. I left the wire on the solenoid for half the trip and i could nail the 30 PSI boost gauge easily. Then i stopped and unplugged the wire from the solenoid. Then....after unplugging the wire, i noticed a EGT drop as well as a drop in boost. With the solenoid "active" i could nail the boost gauge instantly, but with it "de-active" it hits 27, then slowly pegs it.

The whole scenario tells that on the non-ic trucks, you can actually unplug your KSB solenoid for a adavnce in timing of roughly 5 degrees.

Now, could we put the KSB power wire on a switch to activate 5 degree advance when needed? I know it takes time for it retard the timing when the power is turned on to the solenoid, but when we shut power off do we instantly get a 5 degree adavnce? Or do we have to wait for a minute for the wax pellet, just like when it retards itself?

Jeff

 

I'd guess it'd be pretty pokey in both directions, but who knows? I just checked, and sure enough, mine works. I had it unplugged for a while, cause I saw voltage when it was warm and I ASSumed that meant it was advancing the timing. All the time it was un-plugged, it was actually advanced and I pulled the pump back to compensate...huh. Learn something new every day. I'd still like to know where the switch is for the 12v feed and what that switch references--coolant, air etc?

g

 

I'll try to find out where mine is from as well

Jeff

 

I believe these early systems got their power from the preheater control module. (small black box on the driver side firewall under the hood. -below the brake booster.) The intake air sensor on the side of the head inputs to it.
I had no idea that it would affect the timing while driving, or under load. That's new to me.

 

i dunno why but for some reason i can't see any of the posts to this thread unless i keep posting.....

Sorry for this useless post

 

Thanks Torquefan, I'll look for that this morning. I notice voltage to the KSB if I unplug the intake air sensor, so it's gotta be tied to that somehow.

 

ggggggggggggggggggggggggggggggggggggggggggdddddddd ddddddddddddddddddddddd

 

Bill

Are you still running a non-ic pump?


I still have the KSB plugged in, but i only have my timing at 13 degree advance. So if i unplugged it, i would be at 18 degree's adavnce. What you running for timing bill?


Jeff

 

I'll admit that I have no idea what the difference is between the two styles, or if there even IS a difference. What Torquefan said makes sense, but a convincing argument does not gospel make, I suppose. I do know that I looked into the function after I read Torquefan's post. Test light to the KSB when cold, just started, no voltage. Sat there with it for a few minutes and eventually the test light came on. I waited a bit more and, truthfully, did not hear the timing change, but if it is a wax motor setup, it should be gradual. Of course, my truck is a crusty old piece of, well you know, and it could very well have been wired on a Friday or Monday. I guess I'm just really interested in how the silly thing works, since it's obviously somewhat different when compared to the later setup. Back to the drawing board, I guess.
greg

 

Yeah, well, it definately could be one of those mental things too. I'll have to try it again. Maybe i ran into some cooler air half way home . I'm not too sure about the whole thing either, but i did notice a drop in boost for the second half of the trip. I'll try it again...........if it is a wax pellet, things will be a gradual change......


Jeff

 

The Cummins book I have says both styles of KSB advance when energized. Wax type use a coolant temp switch, electromagnetic ones have an air temp switch.

 

mmmm, the plot sickens.

 

I have been doing a little trouble shooting on my KSB system. Mine never energizes even when fully warmed up. I have tracked it down to a temp switch in the intake manifold right beside the one for the grid heaters. This is an air temp switch as was stated earlier. I definately hear a difference when putting 12v to the KSB selonoid.
Just wondering if anyone knows the part # for this temp switch, or where I might be able to look it up on line?