Voltage at starter solenoid

[HelluvaEngineer]

I just went out in the "back 40" to try to start my m1009. It's 24v w./ doghead relay.

I got the glow plug thunk, then turned the key, solid starter relay thunk, but the starter wouldn't spin at all. We've had a long hot summer and it's been cooking some of my batteries, so I suspect that's the issue. I can charge and load test them obviously and I will but I'm curious about something.

My multimeter says the two batteries in series are at 24.2 - 24.4 volts, which definitely sounds low but could be worse. However I noticed that at the relay it was only putting out about 19.4 volts to the starter solenoid. That's very low. Anyone know why there would be such a voltage drop and also if that's theoretically enough to trigger the solenoid and at least get the motor to spin slowly?

Thanks!

 

[cucvrus]

Poor connections, Loose connections, Corroded connections. And just because it has a modified starter relay does not make it infallible. A relay is a rely. It is a control switch to transfer power. Electrical is my weakest part. I still know enough to get by. I would say double check everything and check for corroded contacts or loose connections. What battery clamps do you have. I see the bolt on type with the loose wire clamped down with 2 small bolts. That is a poor connection. I wish I could help more. But with the temperature outside (hypothetically) being 100 degrees all summer long. That should have no effect on the batteries. They are exposed to that everyday under the hood. And the engine still runs at the same temperature as designed. Good Luck. I have no starter mods or relay mods. Never did never will. No need for them. I must have been born with good luck. I never had a issues with the stock relay. The broken record still plays and I believe in what I say. The thunk you are hearing could be a bad starter or solenoid.

 

[HelluvaEngineer]

The starter was just rebuilt by a local guy who has a very good reputation. Of course there could still be a problem. I'll check the batteries and see what that buys me. I believe they are about 5 years old.

I just realized I have a power supply that will go up to 30V. I might test the solenoid on my other starter and see what the required voltage is to get it to fire.

 

[doghead]

I have no starter mods or relay mods. Never did never will. No need for them. I must have been born with good luck. I never had a issues with the stock relay. The broken record still plays and I believe in what I say

I thought Antennaclimber gave you a cube relay that you said was working great(no hacking). That would be a modification.

I also thought I remembered you mention you leave the relays hanging under the dash so you can yank them if needed.

Also, here, you mentioned that the relay is a weak link. https://www.steelsoldiers.com/showt...-system-fire&p=1756327&viewfull=1#post1756327

 

[cucvrus]

Deposition

Do we need to do a deposition on what you thought I said and what I do/did? Yes I have a cube relay in Terminus M1009. Yes. I have had it there. Yes.I have a spare in the glove box also. Your point? NO. I never cut the harness. Stop dogging me and trying to berate me. I did suggest if someone was that unstable about the stock relay to turn it around and have access to the plug. Yes I did say that. I may have done it myself also. Maybe. I do not recall with 100% certainty. So I do not recall is my answer. Would you like time stamped pictures of the stock starter relays in every CUCV I own? And are you going to continue to harass and other wise cross examine and inspect every letter and statement I make. it is apparent that you have issues with my NOT wanting to believe that the starter relay mod is NOT infallible. You had no part in my conversation and I feel you are baiting me to give me another infraction. In all fairness. You even PM me with threats to do so. This is a hobby. I try to help and am NOT always right. I am not in your click and have no desire to be in it. Please back off. The time you PMed me wanted a picture of me sort of still creeps me out. So can we move on with this or are you going to continue to harass and cross examine me on line? Have a great day.

 

[Evil Dr. Porkchop]

Generally when I've got a CUCV that seems fine until you crank its problem is a bad battery. 6TLs, 6TMFs, are absolute junk in my experience, I'll never pay money for one. I think I've lost 3 or 4 in the last year in just a few trucks, even a truck driven every single day. Voltage reads fine until you load test them.

Since we're on the topic of starter relays, I'll go ahead and say that in my experience the stock relay is junk as well. I've had them stick on trucks with good batteries and that are driven everyday. Right now I've got a customer's truck in the yard with a push button starter because that's how they fixed their stuck stock relay. I fixed it with a replacement stock relay but I left it hanging under the dash and I'll be sure to explain to pull that first when the starter sticks on, just like I've done with my own trucks. I believe the TACOM equipment improvement reports even list early truck relays as being highly subject to failure. The "upgraded" relays have worked excellent for me so far.

 

[HelluvaEngineer]

I charged the batteries up to about 12.8v each, tightened all the connections and tried again. Still nothing. I can feel the relay click although as I mentioned I was checking the voltage before.

It may be the weekend before I look more. I'm wondering if something crazy happened like the ground came loose. I had the truck jacked up last weekend with a farm jack due to a tire blowout. Maybe something got loose. The connections on the starter look really good. I checked those.

 

[cucvrus]

As mentioned. Voltage may be there and up to snuff. The amps are more important then the voltage to crank the starter. I think you have starter issues. Bad solenoid or bad connection at solenoid. But I am not there. This is hard to diagnose from the internet. I would start by load testing the batteries and see if the load test. I would move to the starter next. Have it checked by a competent starter shop. Eliminate the internet guess work. Competent means a reliable shop. Not a friend that says he knows nothing is wrong with it. It just bought it last week. Age has no bearing on parts failure. Even corrosion on any relay contacts can create a non contact when the switch is closed. Good luck. Not to beat a dead horse but I think it is a simple starter issue. Have a great day.

 

[HelluvaEngineer]

Have it checked by a competent starter shop

It was rebuilt by a recommended local shop a couple of months ago, so I'm hoping it hasn't already died. I had the guy rebuild two of them for me so I can certainly try the other if the batteries check out. I started the thing this weekend within 2-3 seconds so honestly none of it is making any sense.

 

[cucvrus]

Most CUCV's live in Murphy's world. Once you Masters Murphy's law you and the CUCV become one.


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[h=1]Murphy's law[/h]


Murphy's law is a popular adage that states that "things will go wrong in any given situation, if you give them a chance," or more commonly, "whatever can go wrong, will go wrong." A number of variants on the rule have been formulated, as have several corollaries.
[h=2][/h]

• If that guy has any way of making a mistake, he will.
  • Original phrasing by Edward A. Murphy according to George E. Nichols

• If it can happen, it will happen.
  • Precedent condensed by team members according to George E. Nichols

• If there is a wrong way to do something, then someone will do it.
  • Version attributed to Edward A. Murphy in "Murphy Lives!" by Robert L. Forward, in Science 83 (January-February 1983), p. 78

• If there's more than one way to do a job and one of those ways will end in disaster, then somebody will do it that way.
  • Version attributed to Edward A. Murphy in People Magazine (31 January 1983), p. 82

• Anything that can go wrong will go wrong.
  • Phrasing attributed to Major John Paul Stapp

• If there's more than one way to do a job, and one of those ways will result in disaster, then somebody will do it that way.
  • According to Robert Murphy (son of Edward A. Murphy, Jr.) his father's statement was along these lines; reported in People (31 January 1983), p. 82; alternately reported as "If there is a wrong way to do something, then someone will do it", in "Murphy Lives!" by Robert L. Forward, Science 83 (January-February 1983), p. 78; also commonly reported as, "If anything can go wrong, it will", in The Concise Oxford Dictionary of Proverbs (1982) edited by J. A. Simpson, p. 4.

• Anything That Can Possibly Go Wrong, Does
  • Epigraph of The Butcher: The Ascent of Yerupaja (1952) by John Sack

• Colonel Stapp's favorite takeoff on sober scientific laws — Murphy's Law, Stapp calls it — 'Everything that can possibly go wrong will go wrong'
  • Lloyd Mallan, in Men, Rockets and Space Rats (1955), possibly the earliest printed use of Murphy's name in connection with the law.

• Murphy's Quantum Law: Anything that can, could have, or will go wrong, is going wrong, all at once.
  • Paul Dickson, in The Official Rules (1982) ISBN 0099264900

• If there are two or more ways to do something, and one of those ways can result in a catastrophe or pregnancy, then someone will do it.
  • Phrasing from Jargon File [SUP][specific citation needed][/SUP]

• Smith's Law: "Murphy was an optimist." [SUP][citation needed[/SUP]

 

[HelluvaEngineer]

I wasn't thinking. I have a remote starter switch. That eliminates a lot of variables. I just went back there and hooked it up.

"Thunk. Thunk" - the solenoid is engaging. No motor. It's still in the high 80's here and the mosquitoes were chewing me up, so I'll investigate in the morning. I want to make sure that the cable to the starter is getting 24v (seems impossible to find a ground from under the truck). Also I want to make sure I can crank the engine over with a wrench. I really hope that's not the problem.

Where is the engine grounded? I'm also wondering if it has a good ground. Thanks.

 

[MarcusOReallyus]

Where is the engine grounded? I'm also wondering if it has a good ground. Thanks.

That's a good thing to wonder. Not sure where the ground is, frankly, but it shouldn't be hard to find. Don't just look at it. Corrosion can hide under connections. Take it apart and clean it. Then get rough with the cable - push, pull, shove it around. It's possible to get corrosion wicking up inside a cable. Looks good from the outside, but a mess inside.

 

[cucvrus]

The engine should be grounded from the bottom of the negative buss bar to the intake manifold bolts on the right rear of the engine. The bus bar is on the right firewall behind the battery. You should have a 1/0 cable ground and a small braided cooper ground that is anchored to the firewall. I added a few grounds from the buss bar to the frame and frame to engine. Cured trailer light flicker on my M1009.

 

[HelluvaEngineer]

I got it started. I wanted to make sure nothing was binding so I took a wrench, socket, and extension and turned the engine maybe 5 degrees. After that it cranked right up. I guess maybe there's a bad spot on the flywheel? Perhaps that keeps the solenoid from contacting. Not sure.

Also I checked the ground. It's original and looks good. I didn't see the braided one but I'll keep an eye out for it. Thanks everyone!

Edit: flex plate! Right, my bad.

 

[cucvrus]

The bad spot on the flex-plate could definitely be the problem. But I would suspect it would be grinding and attempting to engage. Are you sure it was not just stuck out there all the time and you turning the flywheel allowed it to retract. I think that would be the case. if it was just bad teeth you would hear the starter spinning and grabbing at damaged teeth. Part way out and jammed you could get the thud you were referring to in the free play of the Bendix. Just a thought and purely speculatory at this point. Glad you have it running. Good Luck.

 

[HelluvaEngineer]

No spinning, no grinding. No nothing. I suspect you may be right about being jammed.

 

[cucvrus]

It's a speculation at best. Like I said. Hard to fix from afar. Your Thud may be my Gnashing. Good Luck report back. Try and eliminate some of the switches and push buttons. As close to stock as possible or purely stock is the way I keep my driving and going. After that the Twilight Zone is the limit. Unable to assist. Take care. The CUCV can be your best friend or worse POS you ever owned. I prefer the easy way. KISS