Hey folks,
Had planned on taking my Breakaway out for an "exercise drive" today, turned the ignition key and the engine would not turn over. On the dash the "low air" warning is audible, and my tranny shift pad lights up with two "N's".
Have plenty of juice from my starting batteries(12.6 on both....just replaced them two days ago(they were getting sluggish after almost six years of usage and would not hold a good charge). Cleaned all terminals/cable ends before putting the new batteries in service.
Now, I had similar issues a week ago, only I was able to "jump" the posts on the ignition solenoid and got the engine to run. The engine would stop running after I removed the jumper wire from one post. After some troubleshooting and a conversation with Kevin(thanks again for your input),we determined that I had a bad ignition switch. Replaced the switch and she has fired up no-problem three times since. So back to today's adventure. After some more troubleshooting, decided to replace the 22 year old ignition solenoid(looks to be original and didn't seem to have a robust "click" when the ignition switch was engaged). So I decided a trip to NAPA was in order to purchase a new solenoid. I installed it....and of course no change. The solenoid is "clicking" when the ignition switch is engaged. What I don't understand is that I have 12.6 volts to ground on both posts of the solenoid(main posts) all the time. I thought that was the purpose of a solenoid, to permit current to flow from one post over to the other post by the action of the ignition switch. This in turn sends current to the starter solenoid which engages the starter. The ignition switch is making the ignition solenoid "click" but nothing is happening with the engine/starter. I am getting 12.6 at the post on the starter solenoid(mounted on top of the starter). If the top of the starter was more accessible,I would jump the solenoid post to the starter post to bypass the solenoid.

Are these symptoms pointing to a bad starter solenoid(mounted on top of the starter)? Or am I just not picking up on something obvious? Hope I used all the correct terminology. I did whack the side of the starter and solenoid a few times with a hammer with no results.

Just about have exhausted my troubleshooting skills and am hopeful someone can send me in the right direction.

6CTA Cummins w/Allison 5sp.
1994 Breakaway XL

quote:

I don't understand is that I have 12.6 volts to ground on both posts of the solenoid(main posts) all the time.

Are you sure the solenoid relay is not the one that engages the house battery bank to the engine battery bank? 12.6 on both sides leads me to think that relay is the auxiliary start relay you are speaking of.
Steve VW, Ham Radio HF, Ed or other members might be able to think of something else.

Thanks for the speedy reply Kevin.
"I don't know" in answer to your question. I've been reading all the posts I can on past Breakaway/Cummins starting issues. I know the solenoid in the electrical compartment is new and "clicks" when the ignition switch is engaged. The solenoid I jumped the terminals on started the engine last week when you and I were troubleshooting over the phone. This solenoid also "clicks" when the ignition switch is put in the starting position.

Ready to pursue any input from the members.

You are one step ahead of me Michael.

I now have the Cummins 6CT 8.3 also but I have no electrical diagrams yet. I will be contacting Spartan after Christmas for anything they have on my coach.

I am a bit confused with the term "ignition" solenoid on a diesel engine. (Even Spartan calls the the key switch the ignition switch!)

I am aware of a fuel shut off solenoid mounted on the engine. It must be energized to get fuel to start and run, then allows shutdown when de-energized.

There is also a power solenoid relay in the front electrical bay. It is energized by the key switch and directs power to the switched power buss there, to energize the various accessory circuits.

There is a starting relay to fire the starter solenoid on the starter itself. This relay is energized by the key switch and supplies power to the starter solenoid. It sounds like this is where you are looking. I do not know the location of this starting relay.

This nearly exhausts my knowledge of the Spartan starting system. Hopefully I will know more soon.

However, somewhere in the starting circuit there must be a switch or relay that verifies neutral. If this does not make, the starter will not run. It sounds like your key switch is clicking the relays so the problem must be downstream. I am not sure where in the circuit the trans neutral switch/relay is found but it may be the problem.

If you can get to the starter solenoid try putting power to the smaller terminal to manually fire the starter. If that won't work you've got a bum starter. If the starter works it points upstream, perhaps to the neutral switch.

A while back at a GTG someone had a phantom starting problem that we fixed by cycling the trans through the gears and back to neutral. Good luck, keep us posted.

Thanks for the reply Steve.
When you mention troubleshooting the starter, there is battery voltage at the main post on the solenoid. So I would jump from this post to the connection with the starter? The smaller post on the solenoid with a small gauge wire attached should be the connection to the starter relay(correct)?

I only have three wires routed from the back of my ignition switch. Might have been a harness and connector at one time but is gone. Looks as though the switch was replaced at sometime in the past. Anyway, one wire is connected to "bat"(has 12.6V), one to "ign", and one to "acc". Beside the "acc" post is another post labeled "sol". Shouldn't this be the post that should have a wire routed from it to the starter relay?(I had been calling it a starter solenoid). This is a GM ignition switch for a 1972 van or truck.

Never been to good at troubleshooting electrical issues.

Yep, just jump from the big hot starter cable to the smaller terminal and the starter should run. If not it is the starter or the solenoid that is bad.

I agree the "sol" terminal on the key switch should be the one to fire the starter relay, which then fires the starter solenoid. Somewhere in between there should be that neutral switch.

I wish I knew a little more of the wiring diagram I could be more help.

The fact that it was previously an intermittent failure implies a poor connection or bad wire someplace you haven't already checked...

good luck, keep swinging, you'll find it.

Jumping the two terminals on the starter (like Steve VW suggested) after you have turned on the ignition key should get the engine started. Turning on the ignition key will activate the fuel shutoff switch. This will work for the Kubota Diesel generator's starter solenoid also. I have had to do it on my Kubota tractor, when the fusible link broke. Which leads me to suggest looking for a fusible link on your rig.

YES jumping the two large posts on the starter should confirm starter motor is OK If the engine turns over, BUT it may not start. The fuel shut off solenoid on the injection pump may not pull in with just turning on the ignition switch.

The fuel shut off solenoid has a high current winding used only during starting and is engaged only when the ignition is turned to the start position. Once the engine has started and the ignition switch is released to the run position, the main coil of the fuel shut off solenoid will hold the fuel shut off to run.

As Steve suggested, try to jump the large starter terminal, the one from the battery, to the smaller terminal, from the ignition to verify that the starter and the starter solenoid is OK. If the solenoid does not click or engage the starter from this test then the starter solenoid is defective. This is assuming you have battery power from the battery to the starter. Jumped into the smaller terminal to the larger terminal will also pull in the fuel shut off solenoid as the start circuit drives both the starter and the fuel shut off solenoids

If the starter does not engage, then jump the two large terminals on the starter solenoid, if the starter does then spin and/or engage that will confirm the starter solenoid is indeed defective. By prepared to loose a screw driver if you do these tests using one to jumper the big terminals. You must use a tool big enough to allow high current to flow, do not hold a wire by hand to do this test, severe burns may result.

If the starter is tested to work OK then proceed to trace back toward the ignition. This may require someone to turn on and off the ignition while measuring voltage.

HTH

quote:

The fuel shut off solenoid has a high current winding used only during starting and is engaged only when the ignition is turned to the start position.

Ed, does this information only apply to the Cummins, or is the starting position true on my Caterpillar 3208?

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My old Mercedes and VW German diesels fuel cut off switches were operated when the ignition switch was activated. Thanks for the interesting bit of "Cummings Knowledge" you have shared.

Yes, all Cummins. Not sure if the earlier models but what is used for Barth coaches would be the same.

Oh and if there is any issues with the fuel shut off solenoid, replacements ARE MUCH cheaper thru internet sources.

12vdc - turn key and 12vdc to the start solenoid - and then to the starter.

On our breakaway or ec2000 spartan chassis the start solenoid is mounted on the curb side frame rail about even with the transmission. Replaced mine a year ago. Also had to run another line to it because the 12vdc wasn't getting there.

How does it prevent starting in gear? There must be some kind of neutral switch… it would be good to know how this is done.

It appears to be the solenoid.
First thing yesterday(before my wife came out to assist), I went from battery directly to the ignition post on the solenoid....nothing. Next for good measure I jumped the solenoid lug to the ignition post...again nothing(yes the solenoid post is 12.6). Wife arrives. Metered the ignition post on the solenoid when my wife turned the ignition key to "start"....I hear the starter relay "click" and I have 12.6 on the ignition post on the solenoid. Again nothing. Then using a shortened battery cable I jumped the solenoid lug to the starter lug...starter motor whirls!
So, with my limited troubleshooting skills I'm thinking its got to be the solenoid. Also can smell an electrical "burnt" odor coming from the solenoid.
Ok, decided to drop the starter,(wife is in coveralls under the Barth assisting). Sucker is heavy and I just about get it out of the bell housing but a blasted hydraulic line(big one) is in the way. No flex to it. Stick the starter back in and secure with one bolt. Looks like I'm going to have to take the hydraulic line loose. It travels up vertically and connects to a beefy 90 degree connector. So, after I take this loose and lose a bunch of fluid, what is the procedure for bleeding the air out of the system upon refill? Worried somewhat with the operation of the fan initially if I get the engine going.
It would be so reassuring if I had an experienced Cummins mechanic to tell me, "I'm 100% sure you have a solenoid problem".
Your input is valuable to me and you guys are the voice of experience.

From your diagnosis it just about has to be that solenoid. Bravo!

(I think I'm in love with your wife… changing starters?… now there's a keeper!)

Removal of the starter is no fun I was told. When I had my coach in for exhaust manifold bolt work it was cranking slower than I liked. I was told it was way easier to replace the starter when the manifold was out (ie from above) I had them replace the engine block heater and the starter at that time. I will take a look at my 8.3 and see if there is a similar layout. Looks like I may have dodged your bullet on that one. Good luck, keep us posted.

If it is any consolation, a good starter is an essential for any diesel. You will have peace of mind when done.

I will see if I can find any reference to hydraulic layout and replacement. Probably Allison stuff… I need info for mine as well.

Hi Michael, I am 100% sure you have a defective solenoid. Your trouble shooting has proven that.

I would not try to replace the solenoid, just get a complete starter with solenoid. It has been my experience that solenoids as they degrade will cause starter damage. Starters need full voltage and current, if any path is bad, starter motors will labor internal heating will cause cintinual damage.

I had a very similar issue with mine last year, when I removed and replaced the starter I took it apart and could see a lot of internal heat damage.

Take your starter to NAPA, I got mine there for $230.00, m,ake sure the starter gear has the same tooth count and the starter gear is the same diameter. I am fairly sure yours is a bigger unit than mine. (I have 5.9L)

Bleeding the hydraulic line should not be an issue if the supply tank is mounted above the hydraulic pump. as long as the pump has oil in it and available to it, it will self bleed. If the tank is below the pump, different issue.

My hydraulic pump also supplies the power steering with the reservoir is mounted above the pump, never has any issue bleeding, just an awful mess when changing steering unit 30' away.

Good luck and great work!