I had a battery short out on my 9680 this spring so I just took it out an ran with two, starts and works great with just the two batteries.

 

What's going on in the world of your battery cables?, Maybe there is nothing wrong with your batteries

 

I would think you have a bad internal connection on a battery. Each cell is connected internally then to the post. A bad connection makes a high resistance and so a voltage drop when high current flows through it. Once that connection fails completely and becomes an open circuit it creates an arc and that initiates that little hydrogen bomb that we all encounter now and then.

So if you want to keep your batteries and get creative i rekon a guy could put a little 12v battery and relay dedicated to operating the fuel solenoid only but if you have established you have a weak battery i would take it out. Then you may be able to actually start better with two if the bad one was shorting out (as this is possible but less likely). If it doesnt work with two then buy a new 3rd battery.

 

Have you tested the fuel solenoid? Maybe it's faulty. Or is there an issue causing the computer to not want the engine to run? I have a hard time believing that batteries with enough juice to crank over an engine don't have the juice to activate a solenoid.

 

I would have the starter checked.by a electrical shop to see what it's drawing. Also try load testing the batteries through the cables and directly at the battery to see if you have a bad cable. Also check grounds between battery and frame/engine

 

I presume you are currently using the manufactures original number and size of battery which would relate to voltage drop if lets say you were using a smaller series of battery all together or fewer of them.

Check the battery voltage when the unit is running to get an idea of what the alternator is putting out when you have no load and then turn the lights and cab fan on to load it and record that voltage just to make sure your charging system is working properly. Then check the battery voltage after its left sit for a day to see what it settles in at and yes a bad battery will drag a good one down to its level as they are tied together but that reading will give some indication.

The other item I never saw mentioned so I may as well ask, did you actually take each and every battery connection off ( is it what may be called the old style with the lead posts ) rather then assume they are good from the outside because they look clean/tight/non corroded, also undo the other end of the ground cable and the positive on the starter to check for corrosion or arcing. The reason I mention the battery cables, years ago we got fooled by a Versatile 850 that had two of those large ( read, expensive 8D ) batteries as everything looked perfect from the outside on each connection but in reality once they were undone, they had been arcing and caused that black hard as glass coating on the posts and the battery connections. It reacted like the batteries were crapped out and yet a hydrometer was showing they were ok in all cells ... all because of bad connections not visible at a glance.

 

Still the same batteries, still cranking no worries, still wont start unless I screw in the over-ride knob.

System voltage not dropping quite as much in this warm weather, to around 9.5 - 10 volts while cranking.

Can anybody tell me, exactly how many volts are needed to energise a fuel solenoid on a Cummins L10?

It has 10.4 ohms resistance. Can anybody tell me how many ohms it should be?

 

hey mate i don't think you need to know the specs on the solenoid, try below - some of which is mentioned above

1.run separate wires from tractor batteries to see if the solenoids actuates -
2. If not run the wires to the ute battery if its running at say 12.5 volts -
3. This will indicate if there is a harness issue or voltage issue and a range it may work in.
4. When tractor is running test alternator out put at 1400 eng rpm should be 14 volts plus or minus 0.5.
5. Disconnect 1 battery at a time if possible to see if issue is eliminated - may show stuffed battery or have load tested - most Tyre shops have a load tester
6. Systems voltage for tractor should be 12 volts - one way or another this needs to be addressed so damage does not occur to other components like starter motor.

Hope this helps...Ant..

 

That should be enough juice to get it going.

Are you working on a mechanical or electronic system?

How does it start when the engine has been running?

 

Is your ground good for the solenoid? Could have enough voltage but with a poor ground it wouldn't go. Have you tried swapping batteries from something else to try it

 

Had you tried like X80 mentioned by directly powering up the solenoid by means of an external battery source but being right there at the solenoid to hear if it clicks as I would presume there will be some slight sound when it engages or disengages internally. Have you in fact checked for power reaching the solenoid when you turned the key on ?

You may very well just have a dead solenoid and a matter of replacing it if it won't function after bypassing the tractors system.

 

If the batteries check out reasonably okay, and you don't want to buy a new set, and the solenoid itself checks out okay as well ,,you may consider what is called a buck-boost DC-DC voltage converter ... available on ebay as well as other places..
Its simply a little module that can take less that12V, in your case 8-9V during cranking, and 'boost' it up to 12-13V quite easily ..it's maybe 2" square and around five dollars .. you need to know how much current the solenoid needs , either from a dealer / service manual, or measuring yourself with a multi-meter as the converters are rated by current capability..
I use them for things like operating newer 12V gauges on old tractors with 6V batteries .. or dropping voltage to put a radio into something that is 24V only..
edit: With your voltage / solenoid resistance, it should draw around 3/4 Amp

 

Kind of a different idea here... get some fuel system cleaner and try it and make sure there isn't and junk in the solenoid causing it to stick..

 

Thanks for the suggestions.

If the engine has been running at operating temperature and I turn it off, then try to start it immediately, it wont start without using the over-ride knob.

With the over-ride knob screwed in it starts immediately hot or cold.

If I connect to an external battery, then yes it starts, as the external battery doesn't drop its voltage when cranking.

When connecting the wire, from the tractor loom, the solenoid makes a click noise as you would expect.

The only time I can do this is when the engine is stopped. You would simply be unable to hear any click while cranking, which is when the voltage is reduced. Unfortunately I don't have a variable voltage machine to test at what point the solenoid works or not.

Once the engine is running, I can unscrew the over-ride knob and the engine will keep running.

With engine running, system voltage is 14.1 volts.

The batteries are not new by any means, but they crank the engine fast enough for it to start instantly.

The solenoid earth is through the body of the fuel pump and engine, so presumably it is okay although it's hard to know.

I doubt if many of the millions of Cummins engines elsewhere in the world have a buck-boost attachment to increase the voltage.

If I had a spec of what level of voltage is required to operate the solenoid, I could make a judgement of whether this one is faulty. Without any spec if I replace it at this stage I am just throwing parts at it.

 

I doubt if many of the millions of Cummins engines elsewhere in the world have a buck-boost attachment to increase the voltage.

If I had a spec of what level of voltage is required to operate the solenoid, I could make a judgement of whether this one is faulty. Without any spec if I replace it at this stage I am just throwing parts at it.

..

The buck boost was only suggested as a solution to take care of the 'symptom' in the meantime, not as a solution to the problem

As others have suggested, checking each battery with a good load tester will let you know if any are noticeably weaker ..
And taking the starter into a shop to be checked for possible higher than normal current draw ..
Or maybe just replace the FSOV, last time at coffee, it was mentioned that these can be obtained for around $50 or so ..
Easier to change and cheaper than batteries or starter ..

 

It should still go down to 8 volts

Maybe I missed it but is it an electronic engine?

What is the voltage at the solinoid during cranking?

I have replaced two ECM's due to loss of voltage during cranking. When the problem first showed up they wouldn't start cold but would start warm.

I just don't know witch engine you got to help point you in the right direction

Also what year is it?

 

Sorry, it's a mechanical engine. Morse cable from hand lever/decel pedal to the fuel pump.

The voltage at the solenoid during cranking is much the same as system voltage, which varies a bit depending on the temperature of the day, but it is around 8-9 on a cold day, 9-10 on a hot day.

1994 model.

 

CTS2, that answers my query for sure as its obvious the solenoid does function with correct voltage and will run fine once the batteries are not under a starter load. So as long as the battery cables themselves are sound ( not corroding internally at the battery end for instance, nor wires breaking apart from vibration at the starter end ) then it could very well come down to batteries and nothing more.

This reminds me of our JD 8970 when it was having a starting issue with a starter that was not up to snuff and not a great starting engine at all regardless, reasonable condition batteries but it all added up to dropping the voltage enough that the GPS crashed because it was on and the voltage dropped too low and it wiped its settings and did that a couple of times on me and so in went a new starter and batteries ( and replaced the key controlled solenoid that actually powers up the starter solenoid ) and it never happened again.

I know it might not be what you want to hear but once batteries do get worn down like that with age it gets to the point where continuing to use them could do in the starter solenoid or even the starter as the solenoid won't "snap in" hard enough and it starts to arc the contacts. Also the alternator works overtime trying to charge batteries that never really take a charge and shorten its life. So one of those saving now things that could cost more a bit later, just something to be aware of.

 

I would defiantly be checking batteries and cables. Thinking it spins over good and there clean don't mean ****.

 

Have you tried running a separate wire from your battery to the solenoid to see if that helps you maverick have a wire with a lot of resistance. Replace the starter with a gear reduction one. Way less draw on the batteries plus it doesn't take 2 guys and a circus midget to install.

 

Why do you not just try replace the solenoid? Sounds like it may be getting weak or has a poor ground somehow.
I'm sure that will be the cheaper option instead of batteries. 10 volts at cranking is should be plenty.