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Discussion Starter · #1 ·
When I got the truck every so often the truck would click and not turn over like the starter was hanging up. Naturally I replaced it with a good replacement starter, but the issue was still there I replaced the solenoid on the fender and cleaned the terminal and everything seemed to be working for a few days then the issue came back.

It seems if I wait until the glow plugs are done clicking on a hot start it clicks and fires away the truck cranks over just fine, very quickly so I wasn't thinking it was a battery. What is an acceptable voltage drop when the glow plus relay is energized? Should my glow plug relays still cycle even when hot? It doesn't do it all the time but about half the times. Sometimes cycling key 3-4 times and it cranks right over.

It's a 1993 f350 7 3l idi factory turbo truck with 194k miles. I have also replaced all 3 battery cables with new cables and cleaned grounds.

Is it possible the new solenoid is alrwady going bad after 1k miles or I'm getting a weak voltage from the ignition? I might just wire a pushbutton start if that's the case.
 

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It is possible. I would check the relay on the fender well, then check the solenoid on top of the starter. If you are hearing it "click", then there isn't anything wrong with the ignition switch, because all it does is pull the relay coil in. The rest happens after the relay pulls in. The reason I advised checking the relay is because the contacts across the two large poles could be burned out, the same on the starter solenoid.
 

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Discussion Starter · #3 ·
The starter is new less than 1,000 miles, probably 40 starts, as is the starter solenoid on the fender.

With key off batteries at terminal are 12.5. With key on and glow plugs kick on, they drop to 11.6. I put in two new Napa batteries key off voltage is 12.7, when glow plugs kick on they are 11.9. I am thinking there isnt enough voltage to hold the solenoid contacts closed when the glow plugs are cycling. We will see if the theory proves correct, it hasnt done it since i installed the new batteries today, but it's only been started 6 times or so.
 

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Does "done clicking" imply that the GP relay is clicking repeatedly? Not just clicking once when the GPs cycle on, and once again when they cycle off? If that's what that implies, then you have either weak batteries, a bad battery connection, or a GP / GP relay issue.
 

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Discussion Starter · #5 ·
Wait to start light comes on for maybe 10 seconds then glow plugs cycle on and off for about 8 seconds after that. They are brand new zd9s, and I made a new harness connecting all 8 gps are relay with 12 gauge wiring.
 

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The starter is new...
That doesn't mean it's GOOD. What brand is it, and where did it come from? Since the symptom didn't change when you changed the starter, you proved 2 things:
1) the original starter is at least as good as (but probably better than) the replacement; and
2) you didn't diagnose the problem - you guessed, and you guessed wrong.
With key off batteries at terminal are 12.5. With key on and glow plugs kick on, they drop to 11.6.
It matters EXACTLY where you put the meter probes, and it matters that you put them in the same place every time. Be specific - where was each probe when you took those readings?
I put in two new Napa batteries key off voltage is 12.7, when glow plugs kick on they are 11.9.
Again: you proved that the original batteries were at least as good as the replacement$, and you're still gue$$ing.

The starter circuit is VERY simple, and VERY simple to diagnose. Study this diagram & its caption:



It happens in 3 major steps:
1) you mechanically turn the key, which mechanically pushes a linkage that mechanically moves the ignition switch;
2) the ignition switch electrically connects the battery (+) to the trigger terminal on the starter relay on the fender, which returns through its base back to the battery (-). When the relay contacts touch the big studs, the battery (+) is then connected to the starter solenoid trigger terminal, which returns through its shell to the starter nosepiece->bellhousing->block->block ground stud->battery (-) cable->battery (-) post;
3) the solenoid's pull-in winding (the stronger one) electromechanically moves the bendix fork to shove the bendix rearward into the flexplate gear teeth. When it moves all the way, the other end of the solenoid hits the switch contacts, depowering the pull-in winding, and powering both the hold-in winding (the weaker one) AND the starter motor, which then spins the engine.

You need to find out where, in that chain of events, your truck is broken.
 

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Discussion Starter · #8 ·
Wow Wheatie that sounds identical to my issue. I did just replace the battery cables, A123-00HP for the positive and a Motorcraft for the driver side and some other brand for passenger but all looked fine to me.

The starter I replaced it with was a DB electrical SMT0018 supposed to be high torque for our engines. Seemed to be identical nose length to the one I removed.

The solenoid relay came from advanced auto but was identical to the one I replaced.

I put the multimeter leads on the driver side battery, directly on the battery posts so I could see it while cycling key inside of cab.

The batteries were mismatched and one didn't have a year sticker the other was 3 years old, I don't mind replacing them to get a matching set in with winter coming, it's a new to me truck. I replaced the cables when I did water pump since it was easy access.

I guess I'll start digging into the issue further once it does it again.
 

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Discussion Starter · #9 ·
I noticed looking at the diagram the small ring terminal that leads to the starter solenoid is on the left side of my solenoid (from memory i think) and the battery cable and glow plug power wire are connected to the right. I dont think it would matter on the solenoid would it? I will switch them around the next time the issue happens.
 

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One side of the relay is always hot, the other side is only hot in the start mode. The lighter gauge wire that runs to the starter solenoid should be on the starter side, to energize the solenoid coil at the same time as the starter. Glow plug, and all other wiring should be on the always hot side. If you put the glow plug wire on the starter side of the relay, the glow plugs will only work when you are on the starter. The same for all of the other electrical components of the truck. The light gauge wire that is by itself is on the starter relay is from the start position of the ignition switch, and energizes the starter relay. Invest in a good multi-meter, and trace the wires out you will find your trouble eventually. It is very likely some little something that you will kick yourself for not seeing.
 

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Discussion Starter · #11 ·
Well i've been using it all week with no issues. Well, one time it clicked once then started immediately but hasnt done it again. Still not sure what it could be. I did notice the tommy gate goes up much quicker. I charged both old batteries on a trickle charge and tested them and they both tested at 1000cas so they weren't bad.
 

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If you have 5sd transmission it has to have enough pedal travel to make neutral safety switch work,mine worked intermintedly because of worn pedal bushings.
 

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But the neutral safety switch doesn't allow it to click, except for the glow plug relay. I'm assuming that the click he has been hearing is the start relay pulling in. Rebuilt starters don't always have new solenoids on them and they use the same contact system that the start relay uses. High amperage (over time) will burn the contacts out. They will drive you nuts looking for the trouble, because they will work one time, but not the next.
 

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Discussion Starter · #14 ·
That would make sense, next time it starts acting up I'll look to buy a new starter. What would be the best place to get a brand new starter?
 

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Go to a starter/alternator rebuild shop and get a new solenoid. It would be MUCH cheaper. If that doesn't cure the trouble then go back to the same shop, and get a set of brushes. While you have it apart, check the bushings.
 

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Discussion Starter · #16 ·
What so strange about all of this is when it would first happen, before I replaced anything it'd take 6 or so key clicks to get it to start, so I switched the starter and it made no difference at all. Then I switched the fender relay and it seemed to go away for a day or two.
 

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Remember my issue was a simple issue with the cable. Look closely at all connection and the ground contacts to block, clean the up to be sure.
 

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Discussion Starter · #18 ·
Yeah I guess I could buy a new cable. The problem it is has only happened once since new batteries but didn't leave me stranded or do more than one click so the issue isn't staying long enough for me to diagnose.

The cables are brand new, I wire wheeled the block and body before reinstalling new ground cables and sprayed with marine corrosion protector. I did the work myself so I know it's all done and tight. I didn't sprayed fender relay connection or starter so I dunno.

I did find a leak that's leaving oil in valley pan, I just replaced turbo and pan grommed, checked pedastal bolts to turbo and they are tight. This truck is having some strange issues haha
 

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I just got a refresher course in starter wiring this morning. My truck did the same thing you described, in the parking lot trying to leave work. It turned out (for me anyway) that the 10 or 12 GA. wire that runs from the starter relay to the starter solenoid broke. I was able to skin some insulation back, and jam it back over the terminal to get it to start and get home. You might be having the same trouble, only inside the solenoid coil. I would replace the solenoid, or take the starter back for warranty consideration. I would also check that wire for good continuity.
 

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Discussion Starter · #20 ·
Just wanted to update since it's been over a month since i replaced the starter. I replaced the DB electrical started with a NAPA New Mitsubishi starter (they looked identical despit the napa being twice the cost), and the truck hasnt done it since. So you were right about there being a dead spot in the starter. I had to pay $26 shipping to send the old one back to DB electrical for a refund, and they ended up just sending me a replacement.... so now i have another door stop that cost me $26 extra.
 
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