View Full Version : Question about starting and stopping the engine

06-09-2009, 12:04 PM
We have a 1983 Newell that my wife, myself and our two dogs are getting ready to travel to the east coast in. We have owned this coach about 18 months and are still learning about its operation. This will be our longest trip since we purchased it and drove it home from Texas a year ago Christmas. The coach was a repossesion and the dealer we purchased it from was not familar with its operation so our introduction was scimpy at best. My concern is with starting and stopping the engine. The engine is a 903 Cummins. On the right rear of the coach is a compartment that has some switches, wiring and solenoids in it. There are three switches in a row near the top of this compartment. From left to right there is a turn style switch labeled starter a toggle switch labeled safety and a toggle switch labled over ride. To start the engine the starter switch must be in the on position the safety switch is on and the over ride switch is off. To stop the engine you must turn both the ignition switch on the dash off and the starter switch in the rear off otherwise the engine continues to run. I am concerned about this if there were an accident the engine could not be shut off from the dash. I am sure this is not supposed to work this way. Can some one help me understand the function of each of these switches and what there position should be to start and stop the engine from the ignition switch on the dash? Thanks in advance for your help.

06-09-2009, 02:17 PM
I leave those Switches at the Rear Panel alone and Start the Coach at the Dash when using my '82. I have found those Switches to be Extremely Valuable when working on the Diesel and I would think that is the purpose of that Panel.
By the way, that area is where the Rear Terminal Strip, Circuit Breakers and Relays are located. The Relays and Circuit Breakers are for the Running, Turn and Brake Lights.

06-09-2009, 04:01 PM
Thanks for your response could you check and let me know what position your switches are set? With the current setting of my switches the engine will crank but will not start with the ignition key I have to turn the rear starter switch on then it will start with the ignition. May be the safety or override switch need to be set differently.

06-09-2009, 04:19 PM
Sure, I will be down to the Coach tomorrow and look at the Switches.
Hopefully Clarke will chime in shortly, he has an '82 as well.

06-09-2009, 05:20 PM
I checked at lunch today and the over ridde switch is a mometary switch that energizes a solenoid when it is held in the on position. The safety switch is in the on position and the engine will crank but will not start if the safety switch is turned off the engine will not crank with the ignition switch

06-09-2009, 05:22 PM
The engine should start and stop from the key by the driver. My coach has only two switches, a toggle Safety and a Start lever. When the Safety is turned off, the vehicle will not start from either the front or the rear. This is used by mechanics to avoid having someone accidentally start the engine while they are working on it. Therefore it should be in the on position. The Start lever is used to actually start the coach. It has an OFF, ON and START position just like the key used to start the engine inside. It should be in the Off position unless you are trying to start the engine from the rear compartment. Having the Start lever in the ON position is likely the reason the coach will not shut off from the inside. That said, the key in the front should start the coach with the Start lever in the centered/OFF position.

Although I do not have the Over Ride switch, I suspect, based on the way the system functions on my coach, it is to be off under normal circumstances and turned on to allow the engine to start with the transmission in gear. My manual indicates that the rear start will automatically bypass the neutral safety switch but I don't have the separate Over Ride switch.

06-10-2009, 11:46 AM
There must be something going on in the wiring I verified last night the coach will not start from the dash ignition switch with the rear starter switch in the off position it will crank but will not start. once started it will not shut off until both switches are turned off. Is there a simple way to determine if the battrey still charges with the rear switch off. Maybe I can start it then turn the rear switch off and only turn it on when I need to start it next time. Thanks for your help and suggestions.

Richard and Rhonda
06-10-2009, 01:22 PM
My guess about the gremlin goes like this. Since the engine will turn over but not crank, and will run but not turn off, that the fuel shut off solenoid is either faulty or wired incorrectly.

If you can get it to turn over, but not fire from the ignition key, it means the engine is not getting fuel.

When you turn off the ignition key, but the engine keeps running that means the key did not turn off the fuel. We have to think differently about engines when talking diesel.

Using the stop toggle in the back could be activating and deactivating the solenoid.

Do you have a helper, so that you can watch the action of the solenoid, or better yet put a voltmeter on it while you try the different switch configurations?

06-10-2009, 01:57 PM
I like what Richard is saying about the Fuel Solenoid. If there was some sort of Voltage Drop or a Bad Solenoid you could see something like this. The Rear Panel is much closer to the Solenoid and may show less of a Voltage Drop.
I had a problem getting my '82 to Start and found part of the Problem to be a Lazy Fuel Solenoid. The other part of my problem was not related to the Fuel Solenoid.
A Volt Meter on the Fuel Solenoid when the Ignition Switch is ON but Engine Not Started is a good next step.

06-10-2009, 02:55 PM
It would be interesting to find the results from the following: Put Safety switch to ON. Put Start switch in the ON position. Try to start coach from the front key. If it starts, go back to the Start switch in the rear and turn it to OFF and see if the coach continues to run.

Let us know the results. Here is my hypothesis. If the coach does start that way and doesn't stop when the rear Start switch is returned to OFF, the key ignition is not sending voltage to the rear to energize the starter circuit. If the coach starts from the front but dies as soon as the rear Starter switch is turned to OFF even though the key is still on, the fuel solenoid is not being energized by the key ignition in front.

06-10-2009, 03:18 PM
With the start switch in the rear turned on the engine will start with the key the safety switch must be on or nothing will happen. The engine will continue to run with either the key or the stop switch in the rear shut off. the engine wil crank but will not start unless both the key and the start switch are on. I am going to sheck tonight if the engine will start from the rear with out the key being on. Thanks for the ideas

06-10-2009, 03:51 PM
OK Jack, now we are starting to hone in on the problem. First, the Safety switch appears to be operating normally. It should ALWAYS be in the ON position for day to day operation. Always leave this ON.

It is normal for the coach to not shut down if EITHER the key OR the rear Start lever are in the ON position. I just tried it on mine. I started the coach from the front, then turned the Start lever in the rear to the ON position, then turned the key off. All the gauges shut down BUT the engine continued to run until I turned the rear Start lever back to OFF (straight up and down). However, if the engine will not start from the back with the key off or from the key with the Starter switch off, the starter is not being energized properly.

I would focus first on the start solenoid (not the starter solenoid). Verify if the start solenoid is activating from the key without the Start lever being in the ON position. I have a start solenoid in the same cabinet as the switches you are referring to. There is a single red w/black wire to activate the start solenoid. That wire goes to terminal 14 on my rear terminal board then disappears into the rear of the panel. It likely goes to the on position of the Start lever with another wire coming in from the key ignition in the front to allow the coach to start from either the rear OR the front.

06-10-2009, 05:16 PM
At lunch I tried to start the engine from the rear switch with the ignition key off the engine would not start. I turned the ignition switch on and it started. what does the start solenoid in the rear panel do? This may be the problem. I will verify its operation tonight

06-10-2009, 05:27 PM
The start solenoid blocks the flow of current to the starter unless it is triggered. There is a starter solenoid on the starter itself.

[on edit]
I went back to the beginning of this thread. When you say that the coach won't start from the front, it looks like you may be saying it will not even try to engage the starter if the Starter switch in the rear is OFF and the Safety is ON. Yet you indicate that from the rear, the Start lever will engage the starter but not start the engine without the key being on. Although that is not the way mine works, it is possible that yours is wired where the key would need to be on to actually start the engine from the rear.

If these statements are correct, that would mean that the rear switches are working, potentially even properly, BUT the key is not able to cause current to flow to the starter when the Safety is ON and the Starter switch is OFF. If this is the case, the problem is likely that the wire from the ignition is not activating the Start solenoid. If the Safety is ON and the Starter switch is OFF and the key will cause the starter to turn over the engine but the engine will not actually start, then the problem is likely that the key isn't feeding power to the fuel solenoid as others have suggested.

06-15-2009, 04:20 PM
I was not clear when I described the problem. The engine will crank wih the ignition key but it will not start unless the rear start switch is on. My diesel mechanic says there is wire on the fuel pump to turn on and off the fuel that is requiring both switches to be on to turn on the fuel. When we return home the ocach is going in and have this problem fixed. Thanks for everyone interest and help.

06-15-2009, 05:12 PM
Yep, if it cranks from the key with the rear Start Lever in the OFF position but will not start until you turn the Start Lever to the ON position, you have the problem that Richard discussed and that your mechanic confirmed that the key isn't activating the fuel pump as it should.

06-16-2009, 09:48 PM
I just got back from moving our '82. Here is a picture of my Rear Panel with the Switches in the Position that allows our '82 to run.
I will send you a PM with my cell # in case you need more help with clarification (sorry I do not have e-mail when not at home).