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Actonhorse

Starter Generator

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Actonhorse

This is the starter off of a 1067. It was sluggish and noisy and would get extremely warm when running for 10 minutes or more. I know it sat outside on the tractor for about 5 years when I got it and it has been "slow" ever since. The bearings feel okay, but I noticed some rubb marks on the inside of the cover. Can anyone let me know if this is normal?

Here are a couple of pics

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post-96-1299846820.jpg

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Actonhorse

Another pic of the inside.

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post-96-1299846913.jpg

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WH nut

It does look bad to me, you know a starter Gen doesnt turn real fast, everyone I have ever had always acts like it has a low battery but always starts. As far as getting very warm, you need to see how its charging, if its over charging it will get real warm. Take a battery reading before starting, then after at full RPM and see whats its doing

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Save Old Iron

My 2 cents worth,

The commutator looks to be very well worn. The commutator is AT LEAST very dirty - which would promote sparking and overheating. The mica between the commutators looks like it needs to be undercut more - this usually is a sign the commutators bars are very well worn. The sharp edges on the commutator bars will cause rapid brush wear, which promotes carbon dust between the commutator bars and again a condition that promotes more sparking.

If the outside diameter of the commutator ring is severely decreased ( has to be measured as a visual is not a good way to tell), the contact time for the brushes to the comm ring is decreased which also lends itself to overheating.

Also hard to tell, but the armature wires usually have more of a copper colored look to them. These all appear darkened, indicating an overheating condition.

Overheating causes metal to expand in the armature and this may be why you see rub marks on the field shoe. The field shoe may just be loose. Check the field shoe bolt and confirm the field coils are the correct coils. Good luck on finding a motor repair shop that even knows what the SG unit is !!!

The field shoe can be lightly spray painted, the SG unit reassembled and spun by hand to see if there is any armature / shoe interference.

If you disassemble the unit again and the shoe has your spray paint scratched off, you have metal to metal contact and a mechanical problem.

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dclarke

Another pic of the inside.

You might want to check how the bearings fit the armature shaft and how they fit in the end housings. A worn bearing housing can sometimes cause the armature to drag on the pole shoes.

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Actonhorse

Thanks all. I made a few calls and did find a small engine shop local. When I started explaining what I had he knew right away what I was talking about. I brought it to him and he confirmed what SOI thought about the wiring being the wrong color and the unit being extremely worn. He feels that the unit has been overheated. He told me he could rebuild it and do the bearings at the same time. Should be good to go in about a week... Hopefully it doesn't break the bank but it should be good for another 40 years!

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qd-16

The last starter/generator I had rebuilt cost about $28 bucks.

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Save Old Iron

he confirmed what SOI thought about the wiring being the wrong color and the unit being extremely worn.

Oh yeah !

another TKO for SOI

nailsmate.gif

Darn smart squirrels, Nature's "A" students.

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sorekiwi

Oh yeah !

another TKO for SOI

nailsmate.gif

Darn smart squirrels, Nature's "A" students.

Well done Chuck!

I hope you dont have any relatives running round in my attic right now. The war is about to begin... :thumbs:

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Actonhorse

Update:

I went to the shop to pick up my SG yesterday and was told that it was "finished". He tells me that the armature is completely done. It has been overheated one too many times. He had a unit on the shelf that he had rebuild a couple of years ago and we made a deal for about the same as a good rebuild would have cost.

I put it on this morning with the same regulator that was on the old one. Here is where I have a few questions.

The new SG turns noticably quicker than the old one confirming the need for it.

I used a multimeter to check the regulator function and here is what I found.

At idle, the cutout contact is open and the charge voltage is at 14.6.

At about half throttle, the cutout contact closes and the charge voltage goes to 17.5 to 18 volts...Yikes...

I am measuring volts at the battery and double checking the "B" terminal on the reg.

the battery is at full charge (charger on all night last night and is less than 6 months old). I have read other posts that say that if the ground is not good the reg will go into full charge mode so I checked all of the ground connections and even ran a jumper from the base of the reg to the battery.

Is there an adjustment on the reg or is it time to get another reg?

The SG was warm within 5 minutes and I don't want to cook this one.

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Save Old Iron
The new SG turns noticeably quicker than the old one confirming the need for it.

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Actonhorse

I just went out and double checked it.

Through the A terminal at idle, the close out relay is open and I have 14.2 volts, at half throttle, the close out relay is closed and I have 18 volts. The same at the B terminal. Should I be worried about the over charging?

The ground through the regulator is good.

Thanks for the warning on the cutout relay, I mistakenly tripped it and it tried to start without the key on. Luckily it was in neutral and turning the key on and off stopped it.

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Save Old Iron

Dean,

my best judgment here is the cut out relay is not adjusted properly. The relay should be closing at about 11 volts on the "A" terminal and opening up again as the generator output drops below 7 - 8 volts.

Add in your over-voltage problem. This condition makes me believe the VOLTAGE cutout relay is not functioning properly. The Voltage cutout relay should be removing the ground from the field coils "F" terminal when the volt out from the gen reaches the regulator set point. So in proper operation, the voltage regulator relay should be opening up at around 14 volts to stop the output from the SG gen to the battery.

Dean, Is this regulator assembly correct for this tractor - have you owned it long enough to know this regulator did in fact function properly at some point in time?

Let us know if this is a 2 relay regulator or 3 relay regulator (just count the number of relay assemblies inside the reg case).

Off to pick up the daughter at the airport - be back later this afternoon for more fun and laughs.

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Actonhorse

Thanks SOI.

It is a 2 relay regulator, 1 cut out relay and 1 voltage relay.

I have only owned the tractor for about 6 months and it was rough when I got it, it hadn't run in about 5 years. I have no idea how it was functioning before that.

The regulator has the 3 terminals on the "back" side and one on the "front" side.

I will try to get a picture up tomorrow.

I see the cutout relay moving but I don't see any action on the voltage relay. I am thinking that I should see it open and close as the battery requires charging?

I did find some info about cleaning and adjusting the relay so I will check it out today and let you know if I get anywhere. It would be easy just to replace it but then what fun would that be!

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Save Old Iron

Dean,

the 2nd relay, the current / voltage reg relay, should actually be "chattering" while the tractor is running.

The windings of the current / voltage relay are activated by either over voltage OR over current. Either an SG output over 13 - 14 volts OR a current greater than 7 - 10 amps will energize this relay - open the relay contacts and remove the ground from the field of the SG gen. Removing the ground from the SG gen will lower its voltage / current output. The lowered voltage current will allow the regulator relay to close again, grounding the field, raising the voltage / current and the whole process repeats itself several times per second - so the relay appears to chatter as the tractor operates.

I would disconnect the battery from the tractor and then try to manually open the relay contacts on the voltage / current relay - just to make sure they are not welded together. Inspect the contacts. If they are corroded, they may be able to be cleaned with 1000 grit wet/ dry paper or a relay contact burnish tool. If they are badly pitted, the reg unit may require replacement.

At this point we are still not sure the reg is the proper one for a tractor. Hopefully it is not designed for automotive applications that allow 30+ amps to flow from the SG reg before the relay kicks in. The wrong regulator will definitely allow the SG gen to overheat.

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Actonhorse

That makes sense, I believe it is the correct regulator because it looks like it it is original. same rust and grime as the SG... I would think that it has been on for a very long time.

I did take the regulator off and check continuity on the braided cable underneath, it is good. I also took the contacts apart and cleaned them.

When I adjusted the voltage screw (turned it counterclockwise to decrease voltage) it caused the contact to chatter and spark between the points at about 2500 RPM. The voltage was still up at about 17 volts. Is it supposed to spark between?

You mentioned removing the ground from the field of the SG... How would I do that? there is a wire going from the F terminal of the SG to the F terminal of the reg...

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Save Old Iron

When I adjusted the voltage screw (turned it counterclockwise to decrease voltage) it caused the contact to chatter -- The voltage was still up at about 17 volts.

A step in the right direction. The chatter has to be seen / heard - a chattering relay is what causes the regulation of the current and voltage.

I would love to see a picture of the "voltage screw" you adjusted - hopefully it was the one on the current / voltage relay.

You mentioned removing the ground from the field of the SG... How would I do that?

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Actonhorse

Here is a pic, the screw I adjusted is the one in the bottom right corner. There was not too much adjustment available and it is loose.

The bottom of the Reg is really corroded due to sitting outside for 5 years or so.

I am thinking that it has been abused for too long and is just not saveable.

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Save Old Iron

Dean,

here is a schematic diagram of the regulator we are dealing with

startgenschematicv3.gif

As far as adjusting your SG Reg unit. the contact assembly on the voltage / current relay can be adjusted. Recenter the adjustment screw and open the gap slightly on the contact points to allow the relay to pull in more easily (at a lower voltage).

Being a trial and error mechanical device, several attempts at adjustment of the relay will be needed. Contact points can be gapped , adjustment screws can be turned and spring holder tangs can be bent - all to set the right physical characteristics of the relay to set the electrical characteristics of the SG Reg unit.

Patience and understanding is required.

That or $60 for a new one - either way will work.

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Actonhorse

Thanks Chuck, I have it wired correctly, now to make the adjustments. I will exhibit the same patience you are using with me!

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Save Old Iron

Dean ,

you still with us?

Tractor didn't bite you again, did it?

I remember getting run over by my first unintended closed cutout relay........

thathelps6.jpg

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Actonhorse

Yeah Chuck, still here and no new burns or tire tracks on me! No mater what I tried with the old Reg it just kept putting out 18 to 20 volts! I found a used reg at a local shop that has been around forever and he advised me on the adjustments. The "new" one started at about 15 volts but after a few minor adjustments is is working perfectly. I ended up getting side tracked with the transmission (complete rebuild) and a "new" B-80 that I found so now I have numerous projects going.....

thanks for the help, I'm sure I'll ask again.

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