4020 Starter

[ronhf]

I think I know what the problem is, but here goes...

4020 diesel started right up this morning, as usual. Shut it down to finish hooking up. Tried to start it again and got a grinding noise from the starter, and it turned over a little but real real slow. A little smoke came out the starter also. I unhooked the batteries and the right one was real low - about 6 volts, but started to come up quickly once it was unhooked. I charged the battery and it load tested good. Went to hook it up and got a BIG spark. Unhooked all wires from the starter and hooked an ohmeter between the battery stud on the starter and the frame and there was continuity.

So based on this the starter is fried as it is not isolated from the frame. Is this correct or am I missing something?

 

[John T]

Welllllllll it may be fried buttttttttt you might disassemble it and there may be an excess accumulation of copper powder/debris thats shorting it out which you might luck out n clean up but I wouldnt bet the farm on it. There may be a serious problem like one of the fields is shorted or the armature.....Im NOT a New Gen guy so take this with a grain of salt...

John T

 

[LarrySTN]

I expect your 4020 is still 24v. If it is.... it is very likely that the starter is the issue..since the "smoke" was left out of the starter. The 24 volt system has constant voltage through the starter at all times (rear lug between the block and starter), so if something malfunctions inside the starter and looses isolation from the frame it will cause the symptoms that you have.

 

[Anonymous-0]

John T, that's a good diagnosis. Its a common 24 volt Deere problem to have a post grounded by the build up of copper filled carbon brush dust.

Gerald J.

 

[thurlow]

If 'twere me, I'd probably pull the starter and take it apart/check it out/clean it up. They are pretty simple......a 9/16 inch starter wrench makes getting the 'back' bolt out a lot easier.

 

[ronhf]

Took starter off and apart. There was some dust near the end cap and I cleaned it out. There was continuity between one battery stud and two brushes, and the other stud and the other two brushes - but not the case.

The armature had one small area where it looks like it spit out some lead, and it rattled when shook, like some small particles are inside it.

The continuity is through the stud - to the brushes - to the armature - to the case.

The starter has a stamp that indicates it was rebuilt in 2005, which is when I purchased the tractor. A refurbished starter from deere is $409 from jdparts.com.

 

[chuck s]

If the starter is indeed fried and it is $400+ for a reman Deere then my opinion for what it is worth is replace it with a reman gear reduction starter from a 8100 Deere. Roughly the same price but you will have to make a new main battery cable and convert the tractor to 12v but hands down will be the best money spent. I did this to my 4320 that has a 4430 engine in it and this engine has never spun so fast.
Thanks chucky

 

[alabamafrog]

I found this old post, let me know if you want me to go in halfers on the 12 longnecks, I’d love to have a few spare starters and gens.

(quoted from post at 12:14:14 02/28/09) I have a wheel barrow full of 24 volt starters and gen.,I'll trade them all for 12 long neck Budweiser's ..

http://ytforums.ytmag.com/viewtopic.php?t=441433&highlight=

 

[4020_1966]

Not much more than the 400 some $ for just the starter gets you the whole kit to convert to 12v, it has everything in it. I am very happy with my 4020 since I converted it to 12v with alternater. My dad still runs 24v with generator on his '64 and I really didn't notice much if any difference in winter cranking on his and mine. The only problems I had after the conversions ended up not being related to the conversion (no gen light=bulb burnt out "about the same time", start button not working=bad wire at nuetral starting switch). I definately suggest not spending any more money on 24v and make your life easier with 12v.

 

[John T]

MY friends 4020 was like that once and then I heard you new gen guys talking about it, fer sure it can happen.

John T (your fellow EE friend)

 

[Mike M]

There is a company that sells starters alot less then that. I have a fyler at home. I don't remember their name.

 

[ronhf]

Got a new starter and tractor is running again. Alabamafrog, I read that old post last night and was thinking the same thing - a wheelbarrel load of 24v starters would have been great to have.

This is the first problem I have had with the 24v system, and I don't have a big urge to change to 12v at this time. If it were causing a bunch of problems I would, but I do like to keep things original and in spec when possible. I did notice on my old rebuilt starter that the armature that went bad was stamped as being made in Indonisa. I am very leary on buying parts from overseas, and my guess is this part was not built heavy enough.