Help! Our 1987 Barth won't start. There's no power to the ignition, but there's power at the batteries. Any idea to help? Also, does anyone have a schematic for a 1986 454, as that's what's in our Barth.Thank you.

Pat, Bob,

Troubleshooting electrics is tough at best even when you're looking at the layout. Over the web, without knowing more, it's thougher. Tell us what happens when you try to start it. Do lights and gauges come alive when you turn the ignition key "on?" Does the starter engage? I don't know Barth's gas engine chassis but usually there is a battery relay that connects the batteries to the electric system. Then, there is some sort of starter relay, either separatly or on the starter itself to engage the starter. If you have power when you turn the key "on," the battery relay is OK. Try to work backwards from the source (batteries) with a $10 multimeter to test voltage. Is there power at the coil with the switch "on?" Do you ger sparks at the spark plug leads (disconnect one) when you crank the engine. Also, some heavy models are equiped with an electric bus switch instead of a battery relay. The internal motor should drive the switch to "on" (you can hear it) when you turn the key to ignition. If you get power with the key "on" but lose it when you try to start, i.e., put a big load on the batteries, it means they're dead. Hope this helps: Let us know.

TheGyrene

I don't want to embarass anyone, however, if you turn the key and nada happens. No sound or anything, make sure you have the shifter in park. If you do and nothing happens then you may have a problem with the switch in the steering column.

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Shortcuts Always Take Longer



[This message has been edited by davebowers (edited May 09, 2002).]

quote:

Originally posted by TheGyrene:
Pat, Bob,

Troubleshooting electrics is tough at best even when you're looking at the layout. Over the web, without knowing more, it's thougher. Tell us what happens when you try to start it. Do lights and gauges come alive when you turn the ignition key "on?" Does the starter engage? I don't know Barth's gas engine chassis but usually there is a battery relay that connects the batteries to the electric system. Then, there is some sort of starter relay, either separatly or on the starter itself to engage the starter. If you have power when you turn the key "on," the battery relay is OK. Try to work backwards from the source (batteries) with a $10 multimeter to test voltage. Is there power at the coil with the switch "on?" Do you ger sparks at the spark plug leads (disconnect one) when you crank the engine. Also, some heavy models are equiped with an electric bus switch instead of a battery relay. The internal motor should drive the switch to "on" (you can hear it) when you turn the key to ignition. If you get power with the key "on" but lose it when you try to start, i.e., put a big load on the batteries, it means they're dead. Hope this helps: Let us know.

TheGyrene

Well, here's the problem. after the winter the rig started right up, then flooded.After several attempts to restart, there was a power failure. I cleaned all the battery terminals and reconnected them. I still have no power to the switch or to the battery isolator. the accessory battery is hot, i can play the radio but no power to switch. The question is then, what is there between the battery isolator and the starting batteries? the the isolator is on the fire wall and the engine compartment is packed and i am unable to trace the cable to the battery.
HELP bob

quote:

Originally posted by Pat & Bob Whitfield:
Well, here's the problem. after the winter the rig started right up, then flooded.After several attempts to restart, there was a power failure. I cleaned all the battery terminals and reconnected them. I still have no power to the switch or to the battery isolator. the accessory battery is hot, i can play the radio but no power to switch. The question is then, what is there between the battery isolator and the starting batteries? the the isolator is on the fire wall and the engine compartment is packed and i am unable to trace the cable to the battery.
HELP bob

This is turning into a web detective story. From what I understand, if you have an isolator, it means you have two sets of batteries: Chassis and House (Accessory). Your radio and whatnot probably runs off the house batteries: it does not mean your chassis batteries are OK. Do you have a starter boost switch (that connects the house batteries to the chassis batteries for starting)? Normally, there is only a 200A circuit breaker (possibly fuse) between the batteies (each set) and the isolator. If you can disconnect the house batteries from the isolator (but keep the chassis batteries connected), you can measure the chassis voltage on the isolator (to test the above circuit breaker). Alternatively, you can disconnect the house batteries. Without knowing more, I'd say your battery/isolator breaker (fuse) was overloaded and opened after you tried to start the engine; or the chassis betteries are dead. I can send you a couple of .bmp schematics (view with ms-paint) of my setup for generic info. However, your coach may be wired differently. Let me know.

Don't give up hope! Cheers,

TheGyrene

Are you REALLY sure the battery is good? The only way to be sure is to have it load tested or put it in another vehicle and observe its starting and charging characteristics. An auto parts store may test it for you. If you have an emergency start switch on the dash, does it start when that switch is activated? Do you hear a clunk under the floor behind the engine when the emergency start switch is activated? My switch is on the left side of the dash and is a rocker switch. If you are sure your battery is good, trace the wires from it. One wire will go to ground. be sure that connection is clean and tight. A very heavy wire will go to the starter. Is there power to the large terminal on the starter? There is a large and a small terminal on the starter. (there may be two small terminals, but wone will not have a wire on it.) Bridge the gap between the large and the small terminal with a piece of metal. Be sure you are in Park for this. If the engine turns over well, your battery and its connections are good. Then you need to follow the wires from the large terminal and check them at the other end. There may be a fusible link in one of the wires. It is a smaller section of wire that is designed to melt if too much load goes through it. Check to see if there is power at the large terminal on the alternator. When you turn on the key, does the fuel gauge give a proper reading? If it does, you have power to the switch. What does the fuel gauge needle do when you try to start? When you are trying to start, honk the horn. If it does not honk, or sounds weak, the battery or a connection is bad. Put a voltmeter on the battery while you attempt to crank. What does it read? As Gyrene has said, there is likely to be a solenoid in the starting circuit. On my 84 it is mounted on a brace on the right hand side above the ingine. It is cadmium plated with two large terminals and two small ones. One of the large terminals should be hot all the time, and the other one should become hot when you try to start. One of the small terminals should also become hot when you try to start, and the other one should always be grounded. If you have a fax, I can send you some diagrams.
Digest all of this, try all of this, and get back here.

Call your mother.

[This message has been edited by bill h (edited May 12, 2002).]