When I was putting the wire harness back on our 3126 Caterpillar, I found a wire labeled "Wait to start". Could not find any reference to it on the FT wire diagrams, never found a place that it hooks to.
This wire does not produce, either a ground, or power when the dash " wait to start" is on. After studying the Cat engine diagrams, then looking at the heater plenum on top the engine, I saw that the solenoid for the power to the heater grid was there. Everything was in tact, except the power side wire that went to a Caterpillar plug was factory capped off, with a Cat factory cap. This told me that in no way was the intake heater ever working.
Obviously it was never hooked up by FT since new.
Our coach was a Texas coach, then a California coach, so no one probably ever noticed. Living in the northwest, I did find it hard to start in extreme weather.
I ran a ground wire back, from a momentary switch at the dash, using one of the extra wire's in the harness to the solenoid ground side. Then hooked a small 30 amp auto breaker and powered it from the plenum hot wire right on top the engine, simple fix. I just hold it, while the "wait to start" cycles.
If you have a 3126 cat, it would be interesting to see if yours is hooked up.
Chris
Chris,
Use the voltmeter on the "engine side" of the intake manifold heater solenoid when someone turn the key to the first position (not turning over the engine). The intake manifold heater is important to starting your engine (actually most all modern diesel engines).
Correct Brett,that would be the way to test the system. One can even feel the heater to see if it's getting warm.
But in my situation, there was a ground to the solenoid. It was grounded to block,but no power wire on the positive side of of the solenoid. It was a short 12" wire, but never hooked up, factory capped off. Not even a power wire in the area.
I will post a picture later
Chris
Here is a picture of the stubbed off factory plug. The wire comes out, goes around 12" to the positive side of the heater solenoid.
I wonder if I have one on my 3176B ?