4020 Starting issue

[MTB]

I have a 1968 JD 4020 12V Diesel. When I try to start, the engine turns over for a second or two, then starter just clicks. One battery is new, second loadtested ok, cable connections have been cleaned. Looking for some advise to troubleshoot.

 

[Bob]

After this episode, do you have to charge the batteries or does it crank again after sitting a couple of minutes?

Makes me think the batteries are not as good as you think OR there's a weird hydraulic problem building up abnormal pressure and loading down the starter.

 

[John T]

What do you know about (quality and workmanship) any 24 volt to 12 volt conversion that tractor may have undergone??? If it was converted and has two batteries theyre now in paralell versus the series used on 24 volt systems. In either a series 24 volt or paralell 12 volt if one battery is weak it sucks away energy and its best if BOTH are similar in size and brand and age and type etc.

Connections, grounds, cable ends and battery condition must ALL be good

John T

 

[MTB]

The tractor is a factory 12V system, side console. After the initial try, the starter will just click, after waiting awhile, it will turn the engine over for a second again, then click. I got the tractor started a couple days ago, let in run for about ten minutes and shut it down and it would restart fine. Yesterday, when I tried to start it, it would only turn over for a second, then click. I am just looking for some suggestions of what can be checked before starting to replace parts so see what works.

 

[4020_1966]

What starter does it have? I would have it tested, and if it is the original it may need rebuilt. It sounds like either the starter solenoid might be bad or the thermal overload is tripping and locking the starter out till it cools. You can check the voltage when cranking, if it is dropping to low your solenoid or the secondary solenoid (if it has one like converted ones does) might not be able to stay locked in. Try jumper cables from your truck, see if it does it still or if it cranks, if it cranks then you probably have voltage drops. If it still clicks take starter in for testing.

 

[Anonymous-0]

Factory 12 volt, side console are characteristics of a 1969, past serial number 201,000.

Check ALL the connections in the starter circuit both batteries both sides from battery to starter solenoid to starter. ANY one of those going bad including the mounting of the starter to the engine can make the starter do what you are seeing.

Gerald J.

 

[Anonymous-0]

The only sane way to check a starter problem is wit a voltmeter($3.50) at Harbor Freight. Check the voltage at the batteries while cranking. It must be above 10 volts if the batteries have been charged. Now take a reading between the motor terminal on the starter and the negative terminal of the battery(we have established this to be a console 1969 or newer model) and this reading must be within .5 volts of the reading you had across the batteries. Now scratch a bright spot on the case of the starter and place the positive terminal of the volt meter here and the negative terminal of the meter at the negative terminal of the battery. and the reading should be .3volts or less. Report back what you find.

 

[francis pawelek]

on my 7020 which is close enough to a 4020,i pull my starter,clean up,reassemble,then start it up, ,,or either turn the steering wheel left to right while cranking,hyd pressure buildup,,
but also,bad connection too

 

[larryanderson]

It seems every time we have a starting issue new JD batteries and properly cleaned and installed cables seem to fix it.It sounds like a voltage problem and 69/72 4020s like clean cables and grounds.Several users install the hydraulic pressure release line but I dont think thats your problem.Good luck!

 

[Tx Jim]

(quoted from post at 23:03:11 03/28/10) I have a 1968 JD 4020 12V Diesel. When I try to start, the engine turns over for a second or two, then starter just clicks. One battery is new, second loadtested ok, cable connections have been cleaned. Looking for some advise to troubleshoot.The tractor is a factory 12V system, side console.

Since it's a '69-'72 model it should have an extra solenoid mounted above starter and I think you find this solenoid is loosing it's ground while you are trying to crank engine.

 

[Anonymous-0]

John T is right! I just went threw this conversion 24 to 12 my 12 volt batterys are 450 cc amps I went down and bought 2 new 850cc amp 6volt batterys hooked them in series and they crank very well they spin better than 24 volt system simple cure for $150

 

[Tx Jim]

(quoted from post at 03:06:40 03/31/10) John T is right! I just went threw this conversion 24 to 12 my 12 volt batterys are 450 cc amps I went down and bought 2 new 850cc amp 6volt batterys hooked them in series and they crank very well they spin better than 24 volt system simple cure for $150

MTB stated his The tractor is a factory 12V system, side console not 24V converted to 12V

 

[4020_1966]

You basically traded an apple for an apple there. 2 12's in paralell that you had gives you 12v 900cca, the 2 6vs in series you got gave you 12v 850cca. There would be no differance between the two unless you had a crappy battery, dirty connections, or a bad wire you replaced with the new wires to go in series with the 6vs. If you really want to start get an 8D 12 volt battery like what I run, its 1600cca 12v. I have that on a good starter and yea it whips it right over and it costs the same as the 2 6vs you just bought and has almost 2x the amps.