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Discussion Starter · #1 ·
Was hauling some brush and the 8n died on me . went to start it and everything was dead. Coasted it and got her going but seemed to have a miss. put her away and the battery was showing 5.6 volts. Battery charged right back up and she started and ran fine. Pulled the positive cable off and she would die. How do I check the regulator and generator to see which one is bad? Little confused because except fo a slight miss she ran home,about 5miles on the low voltage.Pretty sure one or both have gone bad. Also this tractor had been changed from positive grd to neg ground. If that matters. Apparently that change was before the guy I bought it from.It seems to have been charging fine since I bought it. Thanks
 

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I've been asked not to bark.. but I'll start my message with a non barked, but important warning.

The 2nd fastest way i know to damge a charge system is to unload it by pulling a wire off the charge device or battery / load.

it lets voltage go sky high! There are actually different things that happen vs genny and reg and alternator.. however in general.. it's pretty abusive to the system... likle choking a gasser down every day to shut it off.

now that that's been said.. some observations.

1, sounds like a 6v electrical system.

Also sounds like you ?may? have it wired backwards... if it is not positive ground.

positive is ground, negative is the usual hot terminal.

You mentioned puiing the positive off.. can i then assume you meant you pulled the positive bat cable off? thereby disconnecting tractor chassis from battery ground.. something that should really never be done, anyway, during testing.

now.. if it did die, sounds like generaor was not making charge, unless this was at idle, in which case, most gennies won't generate power well at idle.

what does the center 0 ammeter show? charge or discharge?

is the ammeter wired correctly? with engine off and key on, points closed, does it show a 3-4 a discharge.. and a higher discharge when lamps are on? if not, ammeter is wired wrong or not working.

need to have a proper electrical system with working center 0 ammeter to mre esilly diagnose genny / regulator issues.

genny. motor test her.

strip belt off... jump bat hot to armature, and ground field.. genny should spin. if she does, she should charge. only very rarely will you get a genny that motors but does not charge ( generaly is a flaw in the field coil when this happens ).

if it motors, then belt back up and do a voltage test pre start. good battery is 6.3v nominal. after startup, at 2/3 throttle, ammeter should show some positive charge. also votlage on bat should be in the neighborhood of 7.2 to 7.3v ( 7-8 ) is more or less fine.

If lower than that, jump genny field to ground... if voltage comes up, check field wire from reg to genny with a jumper. it's either a bad wire or bad vreg field circuit.

if still no charge, leave field grounded, and then jumper bat to arm. if voltage comes up, you have a bad cutout and possibly field control circuit. ( replace reg if it fails either test and it's not just a wire between genny and vreg ) do test for both using umper wires before replacing a 40$ vreg.

post back if you need more instructons.
 

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Discussion Starter · #3 ·
Ok When I got the tractor 2owners back had reversed the polarity to neg ground remember I asked if there was some reason to do this and after research it was said that it really didn't matter if the genny was repolarized. That said apparently all was working just fine for a long time. Strange I agree but should I reverse it back especially if I need to pull the gen and repair?Battery seems to be 2 yrs old and is apparently still strong since it took charge really quick and tractor started right up and ran fine after charge.
So long answer but Pos is pos.Ok on the ampmeter it does not work. Hasn't since I've had it.Current does pass through but meter doesn't move in either direction.Was on the to do list you know how that goes.Quess tyhat just got pushed up the list real quick!!Thanks for all the input.
 

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if it's a front mount.. I'd swap polarity back if you are doing other work.

if it's a side mount, I'd leave whatever polarity it is, and just make sure coil polarity matched

do repalce the ammeter.. it's a good tool.
 

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Discussion Starter · #5 ·
Thanks Chris. Think it is the reg,cleaned every thing up and pulled the cover on the reg. Points stay open when you turn on the switch. While running if you manually close the points voltage jumps to around 7.5.
otherwise just seems to be the bat voltage. What ya think. Also bypassed the amp meter just to be safe till I can get a new one. Yea it is side mount dist. and coil is wired right.

Just called the Local Implement shop which are our ford dealer, Reg was $30 Napa wanted $82 somebody explain to me the price spread? TSC wants $44 Think the Ford dealer is OK?Is there a major difference in them?
 
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Ford dealer up here sells Tisco as well as Ford. They seem to sell the Tisco cheaper than TSC does. I usually get the Tisco stuff except for points. Ford points recommended by Chris..................
 

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Discussion Starter · #7 ·
Hey Chris I'm alittle confused not questionong your knowledge no way I'd do that!!!!!!! just wanting to understand. The way we always in the old days did a quick check for charging problems was to pull the pos and if it kept running knew it was the battery also in my younger days did some dragging and dirt tract and we never ran batteries in case of fire. Can ya explain to me with a generator how it damages it? Like I said this is more for me to understand.Thanks.
 

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I kinda already explained this.. but I guess if it was worth typing once.. it is worth typing again....with no load, voltage goes real high. there are safe ways to run on a gen with no battery, using a resistor load so that it's not always hunting.

on a gasser like that.. the only normal load is the ignition coil. when points open.. the genny sees no load.. voltage goes hig.

hard on the points

can be thermally hard on the genny. Gennies take it better than alts... field control in the vreg gets double duty on low loads like that.

On alternators.. it's devastating.

sense see's no voltage.. makes charge go to max.. I have seen them spike to 17v when you pull a bat cable.

How about this. You do what you want to your electrical system.

As an engineer.. I'm telling you that electrically, it is hard on the charge system... but as said.. can be mitigated.

there are MUCH better ways to test a system... gennies can be full fielded or motor tested. those are definitive diagnostic tests. those, and a vom and ammeter are all t hat is needed..

that's all I'm saying on the subject.

I'll bow out of the thread now... you've been given enough info to remedy the situation.

soundguy
 

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Discussion Starter · #9 ·
soundguy said:
I kinda already explained this.. but I guess if it was worth typing once.. it is worth typing again....with no load, voltage goes real high. there are safe ways to run on a gen with no battery, using a resistor load so that it's not always hunting.

on a gasser like that.. the only normal load is the ignition coil. when points open.. the genny sees no load.. voltage goes hig.

hard on the points

can be thermally hard on the genny. Gennies take it better than alts... field control in the vreg gets double duty on low loads like that.

On alternators.. it's devastating.

sense see's no voltage.. makes charge go to max.. I have seen them spike to 17v when you pull a bat cable.

How about this. You do what you want to your electrical system.

As an engineer.. I'm telling you that electrically, it is hard on the charge system... but as said.. can be mitigated.

there are MUCH better ways to test a system... gennies can be full fielded or motor tested. those are definitive diagnostic tests. those, and a vom and ammeter are all t hat is needed..

that's all I'm saying on the subject.

I'll bow out of the thread now... you've been given enough info to remedy the situation.

soundguy
Gee Chris I'm sorry if I made you mad honest I was only looking for some info. That's why I said wasn't questioning your knowledge was just trying to benifit from it. I appologise was just wanting to understand again I'm sorry!!!!
 

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Discussion Starter · #10 ·
Replaced the regulator and put in new amp gauge. System is working great except now I am getting 8.7 volts to the battery. Is this too high?Seemed high to me but wasn't sure. Can anyone advise. Battery voltage was 6.9 whe I shut her down. If so is there some kind of adjustment on this regulator?
 

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what does amp gauge show you? it should show an initial high charge that settles down to a just barely positive charge. sounds like it may be staying mid high.. and a 6v bat with a static voltage higher than 6.3 15m after shutdown is for sure overcharging.

dounble check that the ground between the vreg, battery and genny are clean. a dirty ground reference at the vreg will cause overcharging.

more likely it is a cheap chinese reg and tweaked a lil high. if the vreg is non returnable.. tweak the field arm, unless it has an adustable field.. some do.. some don't. make the gap a fwew thou wider. be carefull you do not tweak the arm so that the contacts are not striking off center or canted and not making full contact. vreg tweaking is a dark art.. nearly lost now.

PS. no need to appologize on the above issue. chalk it up to Q & A and flat hard to read typing misunderstanding. wasn't my intention to offend. sorry if it came off worse that it was meant.. brain to finger error on my part.
 

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Discussion Starter · #12 ·
OK the amp gauge is showing initial charge at 9amp and coming down to about 2 at sorta mid throttle. Bat. was showing 6.5 volts at shut down. OK now this reg has 2 sets of points one normally open the other closed sorry but which is the field arm?Thanks

Glad we got the other behind us too!!!!
 

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with the reg on your desk, the set that is closed is the field. the set open is cutout.

but.

if at shutdown it is now showing 6.5v onthe bat.. and the 9a then 2a charge.. it may have sorted itself out.

if the 8.x v you read was with a digital meter.. that could be the issue.. DVM's have a hard time reading v on a genny system due to the spikes and average voltage they make.. and the dvm use a 'window' aperature sampling scheme, and if the timing works out right.. the meter is only 'looking' ont he peaks.. and makes a jumpy or eratic or high reading.
same on points systems when checking ignition issues.. etc..
 

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Discussion Starter · #14 ·
Thanks a bunch. Yea the meter is one of those inexpensive ones. I will just keep an eye on it for a while before I do something stupid. Will just watch the gauge and check the battery regular to see if all is working right. Make sence? Think you told me that about the dvm's before now that you mentioned it. Again Thanks for all the help!!!
 

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cheap analog is fine.. if it's got a needle.. it's ok. cheap digital is where you hit the inaccuracy with brushes or points. untill you get out of consumer grade and into industrial or lab grade digital meter over 100 minimum$$ and probably into the 300$ rnage.. it's hard to get that sampling accuracy.

the amps and static volts you just relayed sound goo.

just watch it for a bit...

make sure no battery boil overs.. or loss of water dramatically..
 
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