Voltage regulator not working

Howdy all, well this is not a car problem but on my fork lift.

I have an old pre 1980's fork lift, it has a 6 cylinder in-line propane powered engine, I had trouble starting it, (slow cranking) so recharged the battery over night. It started fine and I used it for the day, went back a week later and the battery was dead again, hummmmm???

So checked out the battery and it was low, recharged it and it started fine, checked the battery voltage while running and it was the same as when it was off, hummmm.....

Checked the output of the alternator and it was zero volts, traced out the charging circuit and found out that the amp meter was dead,(12 volts on the input, zero volts on the output, internal shunt type) and had been for a long time, so the battery was never getting a charging voltage from the alternator, buy passed the alternator and I got charging voltage to the battery, the bad thing was it was at around 16 volts, (battery was fully charged) disconnected the charge wire to the battery and it jumped up to 35 volts. (approximately)

So thinking that the voltage regulator was bad, I went a got a new one, same problem.

So somehow the voltage regulator system is not working as it should, (new exact replacement voltage regulator) it should regulate to 13 to 14 volts then drop down, what it does is drift up in voltage as high as 17 volts, and before it burns something out I shut down.

So any ideas Guys and Gals ??? This one has me stumped....

Is the regulator a name brand or off shore?

Brand name, got it from O'reilly auto supply, same exact one that was on it.

Standard Ignition 12 Volt Voltage Regulator - VR103

Code:

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https://www.oreillyauto.com/detail/c/standard-ignition/standard-ignition-12-volt-voltage-regulator/std0/vr103?q=vr+103&pos=0

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Also if a battery is not regularly used it could be sulfated and may cause an overcharging that the regulator can't handle. Very rare but could happen.

Battery is about 2 years old, it takes a nice charge from my external battery charger, but without the onboard charging circuit working I might get 6 to 7 starts out of it before it wont crank.(or cranks very slow)

This is an old unit, it looks like someone replaced the old generator with an alternator,(online service manual for this unit shows a generator) but I can't get to the alternator to check the model number without a major tear down of the top frame, (seat, tank mount and safety cage) the alternator puts out 35 volts when I bypass the amp meter but I do not get regulation of the charge voltage, new amp meter is on order.

According to the service manual and on-line info everything looks to be wired right, but I have trouble wringing out the wire harness (hard to reach one side to the other) to see if there may have been something chewing on the wires.

What brand of alternator Terry?Rather than just voltage do you have a way to check the ripple???If it's high voltage, it can be the rectifier related,charging high voltage ac.You must check the ripple too....dvom measured voltage only tells part of the story.

I have no idea on the brand/type of alternator, all I can see is the back side of it, it's a major tear down of a lot of heavy stuff to get to it.

I bought this fork lift used,(from a used equipment dealer) but I wonder if someone just hacked the install of the alternator and it's never been working right to begin with, still digging through the wiring to see if there is something chewed up or not connected right.

Terryl,

Test the voltage in AC mode with a DVM, might be the rectifier is bad or partially failed. Generator is DC output Alternator is AC output then rectified if my memory is working LOL. The rectifier is either built into the alternator or external. Have a look around for it.

Here are some photos, the regulator has been replaced with the same brand and type, the alternator is unreachable without some major work.


Attachment 29415

Attachment 29416

IMO you're gonna have to dig

You can buy a one wire alternator .one wire from battery to alternator.no voltage regulator needed.i have one on my forklift it charges at a certain rpm

I've put too much already into this, new voltage regulator and a new coil,(old one had a weak spark) and again to get to the alternator to replace it is major work.

Terry:that is a Delco 10DN style alternator, & a Ford external regulator.As I stated before, CHECK THE RIPPLE!.If you don't know what it is, it's ac rather than dc current in the charge voltage, indicating a rectifier issue.A rectifier failure can result in high voltage output but it's ac, which is useless to a car battery.

I've had this problem a couple of times where I replaced everything and it ended up being a fuse or a fusable link.

Those terminals on the alternator really need to be cleaned up...............

Quote:

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Originally Posted by The Noof

Terry:that is a Delco 10DN style alternator, & a Ford external regulator.As I stated before, CHECK THE RIPPLE!.If you don't know what it is, it's ac rather than dc current in the charge voltage, indicating a rectifier issue.A rectifier failure can result in high voltage output but it's ac, which is useless to a car battery.

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The VR-103 regulator is listed as a GM part, thanks for the info on the type of alternator, I found a wiring diagram using that alternator and regulator, it looks like there may be a missing connection.

Will check the alternator's output for any AC ripple, if found to be too high then it's out looking for a lift of some kind to get to the alternator for replacement.

Quote:

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Originally Posted by steveOtoo

Those terminals on the alternator really need to be cleaned up...............

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Working on trying to find a replacement at a local auto store,(or Amazon) it's a 60 mile round trip to town around here, not too easy to run down to the local auto shop.

Quote:

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Originally Posted by Terryl

The VR-103 regulator is listed as a GM part, thanks for the info on the type of alternator, I found a wiring diagram using that alternator and regulator, it looks like there may be a missing connection.

Will check the alternator's output for any AC ripple, if found to be too high then it's out looking for a lift of some kind to get to the alternator for replacement.

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You're correct about the regulator.I took a harder look at your image & saw that.

Working on this fork lift is much harder then a car or truck, there are 3 sections of counter weights in the way, and I have nothing around to lift them off, each one is about 2500 pounds, let alone the safety cage and bars that would have to be removed, plus the seat supports and propane tank mount, all this just to get to the front of the engine.

I think it's an old Chrysler engine in there, that's what comes back up in any model/type search in a service manual for this lift, and the bad part is it's mounted backwards to the way you would look at a car or tuck engine, I wish it had a hood to pop open to look at or work on it.

I can get to the oil filter and dip stick, plus the spark plugs (with a little arm bending) if I have to change them, these are accessible via side panels that are removable and don't weigh a ton, the same with the battery and regulator.

All things being equal, if push comes to shove & the alternator is the culprit,I would change it to a 10si Delco,self-exciting model as used in the hot rods,customs,ect.It will fit right in where your old externally regulated alternator exists now, using the same mounting system.You shouldn't have to alter the wiring at all.It is a single wire connection type.

hxxps://store.alternatorparts.com/part-7127m-12v-63-amp-10si-series-self-exciting-alternator.aspx

If it comes down to that I will sell it as is to anyone looking for a fork lift, I will when it warms up a bit, go look into the wiring to the alternator, (after checking the AC ripple) it may have been this way since I bought it.

I don't have the funds to spend on a new alternator right now, the new coil and regulator topped out the budget for the month, so I'm hoping it's just a missing wire or something chewed through on a wire harness somewhere.

Well after further investigation, I looked at the wiring harness, it was a mess, so with nothing else to do I stripped it down (removed all the electrical tape) and found about 15 splices and wires going nowhere, removed the junk, and rewired it, correctly wired the alternator and regulator, and POOF...It works fine, charging is doing about 20 amps, then tapers off, 13.8 volts to the battery after about 10 min, what a mess.

This is what I'm working on.

Attachment 29473

13.8 volts is ideal

Quote:

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Originally Posted by Terryl

Well after further investigation, I looked at the wiring harness, it was a mess, so with nothing else to do I stripped it down (removed all the electrical tape) and found about 15 splices and wires going nowhere, removed the junk, and rewired it, correctly wired the alternator and regulator, and POOF...It works fine, charging is doing about 20 amps, then tapers off, 13.8 volts to the battery after about 10 min, what a mess.

This is what I'm working on.

Attachment 29473

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I got small forklift about same size that is a 2 speed with reverse.What is crazy about is I can replace clutch and pressure plate and flywheel without splitting engine and transmission.I put 1 wire alternator on it all I needed was start and lights

Quote:

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Originally Posted by runamok

I got small forklift about same size that is a 2 speed with reverse.What is crazy about is I can replace clutch and pressure plate and flywheel without splitting engine and transmission.I put 1 wire alternator on it all I needed was start and lights

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I had a 76 Datsun B210 that you could change the clutch without removing the trans. Took 20 minutes to replace.

I know you fixed the problem but if you need a wiring diagram of the GM/Ford VR I can upload a few different ways to wire this combo.........I personally like external VR, when it goes bad in the wrong place or time situation, you can just swap the part without removing the alternator............TP

It's a GM alternator to GM voltage regulator connection, the voltage regulator is an external one and plugs in with a connector, and I think it's an old Chrysler 6 cylinder motor in there, so why would I go with a ford type wiring.

Everything is working, so as the old saying goes, "if it ain't broke don't mess with it".

My Bad, I thought it was a Ford VR, like I mentioned on another thread, I need new glasses........Lol

And I think a GM alternator and a Ford regulator wouldn't play nice in the sandbox together, when friends come to visit and they drive a Ford I have them park on the other side of the house so my Chevy's wont get upset......:sickofme::auto::thud:

Lol, that was funny, if you ever need to combine any of those let me know I have done it........TP

Quote:

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Originally Posted by TurboPirate

Lol, that was funny, if you ever need to combine any of those let me know I have done it........TP

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And I've used a Ford EEC IV spark module on just about everything that needs spark.lol.
Modules,regulators,control units are interchangeable if you have an understanding of their function & basic electricity,and reliable wiring diagrams.I even used an EEC module on a BMW 325i to get a guy home.
Regulators are no different, but input/output values can differ slightly.As long as you know if the alternator generator is A or B circuit, it can be done.I know...I have done it.

I've seen Ford/Chevy combinations, the Kids look funny.

Right you are, from Ford I have used DIS to convert carbs to Fuel Injection using MegaSquirt and Speeduino............exactly that example you used, to get a guy to get to his home it's what I meant when I mentioned I prefer external VR...........TP