Deuce starter problem

[Jake0147]

I seem to have an ongoing issue. When I hit the starter button, it almost always works just as it should. Now and then I get a "click". Not a "clunk" like a starter failure, but a definate "click" out in the engine bay. Trouble is, it's terribly intermittant, and releasing the starter button, then repressing it has always resulted in proper cranking. Including today, except today it took two "re-pressings" of the button...
Of course, after that it stays working, so any diagnostics conclude that the system is working properly...

All connections are clean and snug, and voltage drop testing confirms that the connections hold up well under a cranking load, as well as the relay and solenoid not "dropping" any voltage internally when they are engaged. So the trouble has to be within the relay, or an intermittant open circuit in the pull-in windings on the solenoid, the latter sounding less forseeable than the former?

TMs tell me that the only electro-mechanical parts in this circuit are the relay and the solenoid, nothing else should "click". Searching tells me that the starter relay is semi-unreliable. Is this a reasonable conclusion? It looks like they're a hundred bucks give or take. Is it a reasonable thing to PM at this point, short of a diagnosis, or should I be stringing up pilot lights in hopes of a more concrete diagnosis first? What would you do?

 

[WillWagner]

Mine does the same thing on a very intermittant interval. I have noticed that when it does happen, the volt meter doesn't move like if the starter was drawing too much. I put a button in the truck only because the red looked red instead of pink, and that didn't help. The click seems to come from higher up, so my best guess w/o troubleshooting...'cause it happens so infrequently, is the relay. I notice that it happens more when the ambient temps are low, like in the low 60's.

 

[gimpyrobb]

I have that problem with my wrecker. When I first got it, it wouldn't work at all, so I was happy just to get it going(I did a quick clean up of the contacts inside). Now it really bugs me. I have another starter to put in. I have a 200 amp relay I might try to throw in before I swap out the starter since I have to drop a drive shaft to do that. I will have to keep an eye on this thread to see what works for you. MIne does click more with the colder weather too.

 

[dburt]

Check with Alex at IdahoMotorPool, he has some good used relays for alot less then the cost of a new one. I suspect that either your starter relay is starting to go south, or the starter solenoid. And if both of them are new and good, then the starter could be starting to go downhill. In past experience with antique vehicles, alot of times a starter will have bushings or bearings that are worn, which will cause the armature shaft to allow the armature to come too close to the field windings, resulting in erractic starter performance, and eventual failure. Also, Frank at IMP told me that alot of times the starter button assembly acts up, not letting enough current thru at times to properly activate the starter relay. Whatever that is worth.

 

[m35tech]

I second with Dburt, starter relay or starter selonoid, I would lean towards the starter selonoid....

 

[dabtl]

I believe my first post on SS was a starter not turning over. Someone suggested hitting it with a hammer. Sounded crazy. I hit it with a hammer. Started. Stopped a couple of more times. I hit it with a hammer a couple of more times. Two years later it is still starting. Learned its lesson, I suppose.

 

[cranetruck]

Check the ground wire from the solenoid to the starter ground terminal. If it's intermittent, the solenoid will not keep the contacts closed.

 

[Jake0147]

I did check that one very carefully, but that's an excellent tip for this post. I would not have seen it had I not known to actually look for it based on experience from work. I never saw an externally grounded solenoid until I started working on medium duty stuff.

I assume that this diagram is from the XM757 multifuel literature? What is a "slave (pershing) kit"? Can you really jump start a missile? Just curious.

 

[chvss65]

As crazy as its sounds all electric motors stop in the same place. so over a period of time there is residue and wear on the armature and the spring loaded contacts (forget proper name) so that why hitting it with a hammer works,

or hitting it with a hammer makes a sticky solenoid work

so my vote is solenoid or starter, if your starter and solenoid are off , should be easy to trouble shoot, by jumping onto them separately with a battery charger

 

[cranetruck]

.........
I assume that this diagram is from the XM757 multifuel literature? What is a "slave (pershing) kit"? Can you really jump start a missile? Just curious.

Yeah, the holding coil of the solenoid is grounded externally on these starter motors.

About the slave cable to the missile, the 757 supplied 24 vdc and also had a 10KW genset for power to it. Don't know how the power was used, but the "Pershing" slave receptacle is on the rear of the truck cab. I have been told that the genset was sometimes running while in transit... the 757 was not present during launch, specially equipped m656 vehicles took over over for that part.

 

[cranetruck]

Timed out while looking for images and can't edit my post by adding images, so here are the images that go with the above post. (couldn't even copy the typed message after I timed out to start a new post!).

 

[dabtl]

As crazy as its sounds all electric motors stop in the same place. so over a period of time there is residue and wear on the armature and the spring loaded contacts (forget proper name) so that why hitting it with a hammer works,

or hitting it with a hammer makes a sticky solenoid work

so my vote is solenoid or starter, if your starter and solenoid are off , should be easy to trouble shoot, by jumping onto them separately with a battery charger

And to think, all this time I thought hitting the starter with a hammer was just sound discipline for the truck? Live and learn, I guess.

 

[Jake0147]

As crazy as its sounds all electric motors stop in the same place.

I wish this would act up enough to check that. Trouble is, it might be a month before it does it again if I start it regular. I only started it the other day because we're getting a thaw and I needed to move it forward to make a new set of tire holes in the back yard, before it sunk too deep to move...
I kind of ruled out the starter motor it's self, because to my understanding that like most, the starter solenoid actually engages the pinion to the flywheel, as well as being heavy it's self, so I should hear the "clunk" if the issue were with the motor, including the brushes and windings. FWIW, I am 100 percent confident in the "click" versus "clunk". The relay or possibly the solenoid is making this noise, the starter motor/pinion drive is not making this noise.

I tried it this morning. It won't act up. I tried an extended crank (well, fifteen seconds anyhow) to "warm" any bad connections. It immediately cranked again with no issues.

I thank you all for the wonderful un-consensus... I think by the varied responses so far that all of you who have answered have saved me wasting money on a wild guess instead of an educated one.

I think I'm gonna hold off on the lilely failures approach, and round up four little bulb holders so that I can rig up a "booby trap" to catch this when it happens. I'll think it through more thoroughly first, but I believe that with careful choice of where BOTH ends of each bulb are hooked, then from four bulbs I can collect all the pinpoint test information in one shot for a complete "trouble tree" needed to positively diagnose the whole system at once... Then I'll wait and see. When it acts up, I'll post a conclusion to this, but I don't know when that'll be...

 

[chvss65]

I missed this thought at first

usually when its colder starter motors will act up because the metal shrinks just enough to aggravate the gap between the armature and the brushes in the starter motor

once motor area heats up (engine compartment) or ambient temps go up . it will start normally and you might just hear a clink instead of a clunk, because relay and solenoid are engaging but starter is not. and if it kicks off when you hit it with a hammer I would beleive its solenoid or stater motor
I wish I was there to see it act up. But this is my pass experience my father sold Buicks from 1957, so weve see a few starter problems Haha


But if it got warmer outside, I would suspect the starter motor, we went from 20 to 55 in a day 1/2
But Iam with you check it out 1st
Hope Iam helping and not mudding the water

 

[dabtl]

Do not do as I did and buy a new starter! It may not be needed. Just keep analyzing what is going on to pin point the problem. The light bulb idea is a good one. Post how that turns out.

 

[73m819]

on a older used starter solenoid, the contacts get pitted, the contacts rotate, if two badly pitted areas happen to be in line , presto no contact and no start. a lot of the solenoids can be taken apart, if that is the case, some of the contact discs are double sided, if that is the case ,flip the disc, dress up the conact post with a file, reassemble and you have a rebuilt solenoid

 

[cranetruck]

Typical, bad contact disc.

 

[73m819]

i should have known that Bjorn would have a pic of the contract disc

 

[Deuce_of_Spades]

Bjorne,
So where do you I get a replacement starter solenoid and/or relay NSN #Expensive Thank you.

 

[Jake0147]

It's been a while, but it acted up and I believe I have found my issue. My lights nailed the starter button it's self as the guilty party. There is a very poor connection inside the switch IF you don't press it quite firmly enough, I am guessing that it arcs inside there a little, and spoils the connection. Firm push equals no significant voltage drop. (Measured from he main fuse to the starter relay, covering the whole circuit). Moderate pressure yields two to five volts dropped. Slowly and gently "easing" the button in yields no result except a faintly audible little "tick" from, I assume from arcing inside the housing, Voltage out if it's unhooked but no (significant) current out for relay engagement.
As my volt meter and I were having this epiphany it occurred to me that I have heard of this before but never really gave it a second thought. Now where did I here that again... It took a while, but here it is. Now I will track down a new switch just in case this one is too far gone, which it probably is.

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