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Constant Power Relay

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10-22-2007, 10:32 AM
Bruce & Kathleen
Constant Power Relay
Hey folks! I have been having a problem with my ignition switch lately and remember reading a few posts about the constant power relay in Breakaways going bad. I am thinking this is my problem. I turn the key to the on position and nothing happens. No dash indicator lights, nothing. If I try to start it, it turns and tries to start, but then just shuts off. Now, if I play with the key back and forth between off and on I will get my dash indicators to light eventually and the Barth will start and will stay running. What do you think? Can anybody who has changed the constant power relay in a Breakaway help me with identifying which relay it is in my electrical compartment and maybe even a replacement part number? I am heading out this coming up weekend and would like to alleviate this problem before I leave if possible.
Thanks, Bruce


9303 3855 33BS 1B
Bruce & Kathleen
1993 33' Front Entrance Breakaway
230HP Cummins 5.9, Allison 6 speed, Spartan Chassis, Nicely Optioned
10-22-2007, 10:46 AM
Nick Cagle
I had the same problem with the Regency we just bought. It was the ignition switch itself. Bought a new one at NAPA for about $15.00 and it cured the problem. Oh, the original only had 3 post on the back s start b battery and i ignition. the new one had 4 the extra was a accessory. I just didn't hook up anything to that post.
Nick
10-22-2007, 01:38 PM
MWrench
Here ya go. This is the relay that is the main power relay that is controlled by the switch, the box shows the NAPA part number and that is a spare that I carry along.

This is on a '94 Breakaway YMMV

HTH


Ed
94 30' Breakaway #3864
30-BS-6B side entry
New Cummins 5.9L, 375+ HP
Allison 6 speed
Spartan chassis
K9DVC
Tankless water heater
10-22-2007, 05:30 PM
Bruce & Kathleen
Thanks for the info. guys. I am going to try the relay first and then the key switch.
Ed---My relay is in about the same spot, except it has three posts and I see yours has four. I looked at mine and I do not have the black wire going to the right with the yellow crimp connectors. Any idea what that is for? Do you think I could use the same relay without wiring one of the posts? I guess I could take the one out that is in there and have them cross reference it. Should I disconnect the batteries before attempting this?
Thanks, Bruce


9303 3855 33BS 1B
Bruce & Kathleen
1993 33' Front Entrance Breakaway
230HP Cummins 5.9, Allison 6 speed, Spartan Chassis, Nicely Optioned
10-22-2007, 06:04 PM
Bill N.Y.
What Ed is showing you is an 85 amp constant duty solenoid/relay. The extra wire is a ground wire. Just get that part number shown and run the extra wire to a good ground. It doesn't matter which one of the little wire studs are wired for hot or ground as that solenoid is a non-grounding solenoid.

Here is a constant duty solenoid 4 pole non grounding solenoid
here is an intermittent duty solenoid 3 pole grounding solenoid

If you use the 3 wire solenoid from the link above in a constant duty application you will breakdown. It might look like the right one, it isn't.

Some of the 3 wire constant duty solenoids are of the grounding type. if you buy on of those and then send power to the little terminal you'll blow the ignition fuse. Those are used in liftgate operations with a grounded switch.

..Test First... Do not become a parts changer.
First, turn on your key and then take a test light to your solenoid. Every post on the 3 wire solenoid will be hot if it is working properly. If the little wire is hot and only one of the big wires is hot then you have a bad solenoid. If the little wire is not hot then you most likely have a bad key switch. If none of the wires are hot then you need search some more.

Buy the 4 pole non grounding relay and add in a ground wire. You'll be happier.


˙ʎ˙u ןןıq- „ǝןƃuɐ ʇuǝɹǝɟɟıp ɐ ɯoɹɟ pןɹoʍ ǝɥʇ ʇɐ ʞooן ɐ ƃuıʞɐʇ sı ǝɟıן oʇ ʇǝɹɔǝs ǝɥʇ„

Regis Widebody1990 Barth Regis Widebody
8908 0128 40RDS-C1
L-10 Cummins
Allison MT647 Transmission
Spartan Chassis
Regal Conversion1991 Medical Lab Conversion
9102 3709 33S-12
Ford 460 MPFI
C6 Transmission
Oshkosh Chassis



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10-22-2007, 06:16 PM
MWrench
quote:
Should I disconnect the batteries before attempting this?
Thanks, Bruce


Absolutely remove the ground wire from the batteries BEFORE you work on the relay. It has a large wire from the battery and can deliver a LOT of current if you should happen to get a wrench or heaven forbid a wedding band across the +12V to ground, it has happened!! Even thou +12V doesn't sound like much and you probably will not get a shock from it (I can feel it in the fleshy part of my arm) there is enough current to turn a large chunk of metal cherry red in no time at all.

I believe that my original solenoid had three terminals but when the PO replaced the solenoid, this is the only part he could get. Yours has an internal ground whereas the one I showed has an isolated energizing coil and as Bill has said, either terminal can go to the key wire and the other goes to ground. It is fairly obvious that the ground wire to my solenoid is not factory original.

HTH


Ed
94 30' Breakaway #3864
30-BS-6B side entry
New Cummins 5.9L, 375+ HP
Allison 6 speed
Spartan chassis
K9DVC
Tankless water heater
10-22-2007, 06:34 PM
Bruce & Kathleen
Thanks Bill and Ed! Please keep in mind you are not dealing with a person who is mechanically inclined, but I do have a test light and will check the relay terminals first. That brings me to another question and if it is a thread drift, I apologize. I hope this doesn't look like I am more than a dummy than I am, but which batteries are the house batteries and which are the chassis batteries? Would it be the chassis batteries that are wired thru this power relay? It would be a good idea for me to disconnect the proper batteries if I need to change out this relay (or is it actually a solenoid like those found on old Ford's starting circuit?).
Thanks, Bruce


9303 3855 33BS 1B
Bruce & Kathleen
1993 33' Front Entrance Breakaway
230HP Cummins 5.9, Allison 6 speed, Spartan Chassis, Nicely Optioned
10-22-2007, 07:29 PM
Bill N.Y.
quote:
Originally posted by Bruce & Kathleen:
Would it be the chassis batteries that are wired thru this power relay?
Yes.
quote:
Originally posted by Bruce & Kathleen:
...is it actually a solenoid like those found on old Ford's starting circuit?.
No. The nature of a starter is intermittent. If you hook up a ford style starter solenoid it will burn up and leave you on the side of the road.


I do hope we are talking about the same thing. If you leave the key off and the two bigger wires are hot then you are not looking at the ignition solenoid.


˙ʎ˙u ןןıq- „ǝןƃuɐ ʇuǝɹǝɟɟıp ɐ ɯoɹɟ pןɹoʍ ǝɥʇ ʇɐ ʞooן ɐ ƃuıʞɐʇ sı ǝɟıן oʇ ʇǝɹɔǝs ǝɥʇ„

Regis Widebody1990 Barth Regis Widebody
8908 0128 40RDS-C1
L-10 Cummins
Allison MT647 Transmission
Spartan Chassis
Regal Conversion1991 Medical Lab Conversion
9102 3709 33S-12
Ford 460 MPFI
C6 Transmission
Oshkosh Chassis



Quick Link: Members Only Link To Send Me A Private Message
10-22-2007, 08:51 PM
MWrench
I went back and edited my original picture to show which line would be hot all the time and which should get hot with the key, hope it is clear, please go to my original post for a look.

HTH


Ed
94 30' Breakaway #3864
30-BS-6B side entry
New Cummins 5.9L, 375+ HP
Allison 6 speed
Spartan chassis
K9DVC
Tankless water heater
10-23-2007, 11:44 PM
Gary Carter
I used a 3 wire constant duty relay. They come both intermetant and constant.

You need the 3 wire that is internally grounded. The folks at NAPA can show you the pictures.


'92 Barth Breakaway - 30'
5.9 Cummins (6B) 300+ HP
2000 Allison
Front entrance
10-24-2007, 09:44 AM
Bruce & Kathleen
I thank all who have responded to my post, but now I am a bit confused. Do I use the 3-wire or 4-wire? It seemed to make sense to go to the 4-wire (which I picked up yesterday for $52) and add an external ground. But, if for my application I should replace the 3-wire with another 3-wire, then that's what I will do. My Breakaway is probably the same as Gary's and do not know if that makes a difference compared to Ed's. I am waiting for the rain to stop so I can check my conditions as suggested and make the needed repair (relay or ignition switch), but want the proper items to do it all at once.
Thanks, Bruce


9303 3855 33BS 1B
Bruce & Kathleen
1993 33' Front Entrance Breakaway
230HP Cummins 5.9, Allison 6 speed, Spartan Chassis, Nicely Optioned
10-24-2007, 10:48 AM
MWrench
It really doesn't matter if it is a 3 or 4 terminal (wire) solenoid. With a 3 terminal solenoid, it will go right in without need for any further effort. With a 4 terminal solenoid, you will have to add the ground wire.

If the solenoids are rated the same (3 wire or 4 wire), then there should be no difference in operation or reliability.


Ed
94 30' Breakaway #3864
30-BS-6B side entry
New Cummins 5.9L, 375+ HP
Allison 6 speed
Spartan chassis
K9DVC
Tankless water heater
10-24-2007, 10:57 AM
Bill N.Y.
quote:
Originally posted by Bruce & Kathleen:
Do I use the 3-wire or 4-wire? It seemed to make sense to go to the 4-wire (which I picked up yesterday for $52) and add an external ground.
You can use a 3 wire or a 4 wire constant duty solenoid. I only carry the 4 wire constant duty solenoid on my service trucks. I can use this item in a grounded circuit, a hot circuit, as a constant duty and as an intermittent duty solenoid. My use of the 4 wire constant duty solenoid is the multitude of applications that it can be used on.

All that being said, I would tell you to use whatever you feel comfortable using. Myself? I would place the 4 wire solenoid in there only if the testing showed me that it needed a new solenoid. Besides, you've already purchased a 4 wire solenoid. If you need it, use it.

Also, when you go to test the original solenoid, use a ground that is not part of the circuit panel. If you get power to the little wire (key on) but not to both big wires take the pointy part of the test light and touch the case of the solenoid, if it lights up then you have a loose or corroded solenoid case or the mount for the bracket is not connected.


˙ʎ˙u ןןıq- „ǝןƃuɐ ʇuǝɹǝɟɟıp ɐ ɯoɹɟ pןɹoʍ ǝɥʇ ʇɐ ʞooן ɐ ƃuıʞɐʇ sı ǝɟıן oʇ ʇǝɹɔǝs ǝɥʇ„

Regis Widebody1990 Barth Regis Widebody
8908 0128 40RDS-C1
L-10 Cummins
Allison MT647 Transmission
Spartan Chassis
Regal Conversion1991 Medical Lab Conversion
9102 3709 33S-12
Ford 460 MPFI
C6 Transmission
Oshkosh Chassis



Quick Link: Members Only Link To Send Me A Private Message