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Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 1:03 AM

Hello...i got this new mechanicc onsite. It seems that since he'd been here alternators & starter motors of most of my forklifts and trucks are burning out /not chargin/ and not working properly. So i wonder why this is so. Is it he who is to blame?? Therefore, my unansswered question is ; Why do alternators and starter motors burn out quickly. Anbody out there, pls give some idea. Thanks in advance, Hubert.

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#1

Re: Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 10:42 PM

Pls check capacity & branded material, dont repair somuch just replace....

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#2

Re: Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 10:58 PM

Some different possibilities come to mind.

Firstly, Was all the equipment purchsed or last serviced at around the same time? It may just be they are wearing out together and is co-incidental to your new recriut.

Secondly, it may be that he is able to "diagnose" defects in alternators and starter motors before they actually fail, so your repair bill is increased by his preventative fixing of deteriorated parts.

Finally, the failures could be related more to the users than the service guy. Holding a starter "On" too long for instance can create issues.

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#3

Re: Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 11:17 PM

the right motor and alternator should last quite a while if properly installed.

Often there are shims and adjustments required to get the correct fit/tension in these things. Improper installation = early failure.

On the paranoid side, is there a chance you are buying a new motor, and he is installing it, and he is getting a broken part from another fork lift place and replacing it with your good one, leaving you to buy a new one and him with some cash in his pocket?

We call this a 'fiddle', and clever people have been stealing this way since Roman times.. This can only be done if he has time and opportunity.

How to defeat this? When you buy a new part, make a concealed scratch mark in a place only you know on the part, and observe when it fails if this is the same part.

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#6
In reply to #3

Re: Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 11:50 PM

normally i'd check the regulator to ensure there is no overvoltage, otherwise the Engineer and Aurizon have covered it really.

Basically they shouldn't be failing. I'd get the units tested before repairs are undertaken, sounds very suss to me! YOu want to get all parts and work listed so you can tell how they fail, is it electrical (wiring/switching) or mechanical (bearings). Make sure no one is electric welding near the forklifts as this can stuff the alternator from em effects. However starters are particularly rugged bits of equipment, however sometimes youcan replace the same one several times before you find the cause of the fault....Do you do the repairs in house? He may a) like working on alternators and starters or b) have a mate he sends them to to get fixed...check with his previous employer and see why he isn't working with them!

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#36
In reply to #6

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 5:28 PM

thanks Guest, will update all thread members on the details. we dont do the repairs inhouse. we submit to outside service workshops.

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#37
In reply to #36

Re: Why do Starter Motor & Alternators burnt too quickly?

09/11/2008 7:11 AM

It may be that the outside service company. They also may have some one new that is not doing proper or incomplete repairs and testing to the parts.

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#4

Re: Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 11:34 PM

A good place to start is with what water are you using in the batteries. This is a personal experience when I was with the Corp of Engineers in Vietnam. We went through many, many starters and batteries because we had no distilled water for the batteries. Now these were the very large batteries found in D9 cats and big road building equipment.

Look to such basics and you should find your problem.

"Lucky"Chucky

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#23
In reply to #4

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 7:10 PM

THanks freflyt, it is always checked that all battery water is with limits. We always use dilute water (distilled from our QC lab) to put into the batteries. What do you say, is distilled water different to dilute water? Please reply this thread. Thanks in advance, Hubert

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#25
In reply to #23

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 7:29 PM

distilled water has no dissolved minerals. If water is used and the battery overcharged some is electrloyzed into H and O, which vent into the air unless you have a platinum foil cap. As you can see if you keep adding minerals and losing the H and O, in time you will have a high concentration of assorted minerals in the battery and some insoluble sulphates will form and acid will vanish. In time this sludge can fill the battery from the bottom up. Deionized water is not OK, it can have dissolved non ionizing metarials, distilled is what you need better

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#29
In reply to #23

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 11:00 PM

That I do not understand as to make "dilute water" you need to add rubbing alcohol to make it. This will most likely be adding minerals to the water, this would cause the batteries to get weak and weak batteries put a strain on the starters and alternators. This seems to be a natural link because there are unrelated components going out that all have a common thread.

This common thread could be just the water you are using and is the best place to start. The next place to look is the system grounds, this is the next place to look. I have fixed many of starter problems with just replacing or re-grounding all the grounds.

Just get some plain cheap distilled water for the batteries, they will live you for it.

"Lucky"Chucky

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#30
In reply to #23

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 6:14 AM

What the hell is "Dilute" water????

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#32
In reply to #30

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 6:40 AM

Dilute water is made from pure or active water diluted with a diluent. It is far more palatable than pure water. The diluents are chosen by how smoothly the combination slides down the throat.... pub night shows the diversity of diluents available.

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#5

Re: Why do Starter Motor & Alternators burnt too quickly?

09/08/2008 11:39 PM

Some mechanics are no good at D C electrical repairs. While good at other thing that is one place they are just useless.

I did catch a mechanic once who was doing a lot of work at home on other peoples cars and he was taking our new parts. Al to fork truck parts will fit autos espically GM staters and alternators.

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#24
In reply to #5

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 7:18 PM

i think i'll get your assumpstion...maybe my new mechanic is just not good enough to DC electric parts......

But his does not bring do side deals at the moment coz he sleep right here onsite, near the workshop, and always under my watchful eagle eyes.

Thanks mate, Hubert

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#7

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 1:20 AM

Happened the same to me without great solutions but:1)Starter motors:Take care the gas oil tank be loaded or the technician will purge it using the starter motor each time it gets without fuel,even more:they will use 24v even when it is just 12v.Also possible you destroy a starter each time you rebuild an engine for the same reasons.2)Generators:may be you take them to the technicians sometimes and they says "whats the problem? is alwright" don't change the generators in differents machines with differents pulleys or won't charge properly.Also you work at nights? did you add a lot of new lamps? do the lamps remains turn on when it is on idle?do you care your batteries?

Sometimes and just sometimes i believe it wasn't properly fixed,or with not good spare parts.

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#26
In reply to #7

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 7:31 PM

my trucks and forklifts work 24 hours a day..al round the clock. We a cement producer and supplier firm. Oil tanks are checked daily and replenished. I ensure that original as designed pulley belts are used on alternators. No additional lamps are added. And of course daily checks are always conductsed on batteries. theres a multi-purposes battery handy too when batteries are flat

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#8

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 2:50 AM

I could suggest the following points :

1) Please ensure that the starters / alternators are not overloaded

2) While boosting from one battery to another, proper care to be taken.

3) if the technician, has rewinded the armature ( in case he has re-winded ) then, the wire guage has to be checked

4) Please check the fly wheel gears. if those are worn out, the load on the starter will be more which will produce heat the there by the armature will get affected.

5) water should not be allowed inside then starters / alternators. Normally this happens when the equipments are washed.

6) After 1000 hours of operation ( approx ) it is better that the starters & alternators are removed for checking as a preventive measure.

7) use of genuine spares

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#9

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 4:23 AM

How often they get burn out?

If you are a large establishment and have a lot of use of your machinery on the daily basis then these sort of things can happen.

Also, does he do a complete overhaul on things or only replaces the faulty parts to leave some work to be done always for himself?

It is not normal for alternators to burn out often not even for starters providing if things maintained properly.

I think you should look into it more closely! Is he a contractor?

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#22
In reply to #9

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 5:51 PM

Remember, the generator is an actual power station on board that runs everything you hook up to your vehicle, not the battery! On top of that the generator must also have enough power to charge the battery.

Most people mentioned already that cheap parts can often play part however, the unexpected burning out of a generator is still very unusual under normal circumstance.

If this happens often, and I suppose in your case can happen even to the almost new ones as well, then make sure that your mechanic does not install many heavy duty loads (extra head lights) on board including the replacement of the original head light bulbs with some substantially higher rated ones. They can easily over load your generator and cause it to burn out incl the diodes.

Basically, you must sum up the max total instantaneous power requirement needs (in Watts) of your vehicle in order not to exceed the power rating of the generator including charging power.

For a stater to burn out prematurely is a mystery, you don't even have a really cold climate in down-under. Maybe this is where the cheap parts come into play.

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#33
In reply to #22

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 9:38 AM

Maybe this will solve all your problems and this happened to me many years ago.

I used to live and work in many places in Australia and once my starter motor went bust in my car. I took it to the local workshop and they gave me a replacement one for the generous sum AU$85.00 and trading in my faulty one.

When I installed the repair/reconditioned starter its clutch was slipping so much that it would not be able to give the engine any move even let alone turn.

When I returned it the guy was doubting what told him but after raising my voice at him he then gave me another straight out of another car that was still oil stained and that was ok.

This is only to show that a lot of repair shops do not even do a good repair job because many of the people they employ hardly understand the concept of things let alone know what they're doing.

Sadly, this has pretty much became a standard these days around the world when idiots are doing repairs nd working on stuff they hardly know about. They are often hired in the name of cheap labour.

Those who run the repair business want quantity not quality and your mechanic might be just a victim, in your eyes, since he does the replacing.

If, he's also involved in the service and repairs of them then, he must be a bit of a fruit cake on this topic and then you have the right to suspect him of not doing something right.

I do know a lot about these things because when I was a teenager, from the age of 17, for over two years I used to repair many of starters (small to large) as well as generators on a daily basis and used to test them on proper test benches.

What I see and read here on this blog is nothing more than on confusingly stupid and down right inane comments and suggestions. Yesterday, I read from someone who was quoting other peoples' ideas without knowing what is going on and telling how the accumulator (battery) supplies power to the vehicle during operation.

The reason why I suggested to you yesterday to avoid using too many extra head lights and other heavy, electric, loads (I am referring to trucks) because I know that in your neck of the woods it is quite common to do that due to long open country roads to be on a look out for Kangaroos, Wombats and...what have you.

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#28
In reply to #9

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 8:38 PM

for past 3 weeks there were 3 starter motor problems, and 4 alternator problems....

and i agree with your second point, we are a large establishment.....but we've successfully didn't face this until this new recruit came...

He does not completely overhaul startor motors and alternators....

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#10

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 7:50 AM

Hubert,

Seems to me, if your mechanic is rebuilding the starters and alt's with wrong components then, yes they will fail prematurely..... OR all of your vehicles have rising grounds.

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#11

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 8:02 AM

There's a lot more going on here then we have data to understand. I would suggest you try to get life data on the parts and then work from there. Generally there is probably no reason why a new mechanic would be causing the problem unless he doesn't know how to service that particular type of part.

Maybe you could take a burned out unit to a third party and get them to diagnose the problem?

You're going to need a fair amount of other information before you can come to a solid conclusion.

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#12
In reply to #11

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 8:14 AM

That got a GA vote from me. I read all the other responses, most are good, a few seem contradictory of each other, but none can claim to be definitive without knowing a bit more about the actual conditions.

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#13

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 8:30 AM

I know here in the u.s. , I have personally run into a lot of inferior made parts and sometimes have had to get the same part 3 or 4 times before getting one that is not inferior . So much is outsourced to China and it s quality is crap.

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#14

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 9:57 AM

there hubert

your problem is autoelectric system

chek you batre amper hour,and voltage

are your consumption are same with your alternator and motor starter use

chek your cable are have any contak with body engine (phase only)

chek are your motor starter and alternator was fill in water

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#27
In reply to #14

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 8:05 PM

thankyou taufik, message copied...

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#15

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 11:56 AM

Has the mechanic switched the supplier of the parts?

Has the supplier switched the source of parts from a name brand manufacture to a cheaper off shore builder?

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#16

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 12:26 PM

My father is in the starter / alternator business. He told me the #1 cause of premature alternator failure is a weak or undersized battery. The alternator is trying too hard to charge the battery all the time and it overheats and breaks down. The battery acts like an electrical reservoir, but if the reservoir is low, you are running the truck off the alternator. Your alternator is designed to trickle charge the battery, not run the vehicles electrical system.

#2 Problem? Crappy parts. He has seen new units fail as often as rebuilt due to defective components. Go to a rebuilder you trust. Many rebuilds come from 3rd world countries and only standard parts are replaced, regardless of what the original problem was. It usually pays to get the more expensive rebuild. But who knows, you could be lucky.

His favorite customers are those who bought their starters and alternators from a national chain that offers lifetime warrantees. Sure enough they get free replacements, but they become his customer after changing out the 3rd or 4th one and become tired of busting their knuckles.

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#17

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 1:45 PM

Hi Hubert,

Ferquiza has a good point with the pumping of diesel to the injector pump. Most starters are only rated at 15 or perhaps 30 seconds. If your new mechanic is routinely letting the fuel drain back to tank and then pumping it back up with the starter motor this may well result in a burnt starter. We see a lot of this on the yachts and we normally add an undersized fuse to the circuit which will blow at about 40~50 seconds. The fuses cost about 20€ but that is a lot cheaper than a 1000 ~2000€ starter motor. Over cranking is about the only way you can burn a starter. Weak batteries or starter cables will turn the engine slowly and may be enough to cause the problem.

Ref the alternators, the view expressed by Accudave is entirely wrong. The alternator DOES run the vehicles loads and charge the battery. The battery is there to provide power to start the engine and act as a stabilizer to the DC voltage. A short circuit cell in a battery will cause the alternator to charge very hard and may cause a diode burnout. This would also cause poor cranking…. See para 1

Has your mechanic changed your battery supplier? Or tried to save you money by choosing a cheaper brand of batteries?

What is he doing different to he last mech you had on team?

Best of luck

Chas

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#18

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 2:08 PM

Hi..If your forklifts are operated continiously at higher ambient temperature and if there is no proper cooling for the motors & alternators & at the engine compartment then you may have quicker burn outs.

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#19
In reply to #18

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 2:37 PM

Another cause may be because of weak batteries causing longer cranking time.Other cause is when starting the engine, if the hydraulic pump is loaded due to the control valve spool opened to the hyd cylinder,it may result in overloading the motor causing it to heat or burn later.

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#20

Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 3:02 PM

Hello hubertooru:

Regarding the starter motor, I think they burn out simply because it has to turn-over a stone cold engine with moving parts weighing several hundred pounds?

I think it may also be that the alternator actually moves faster than the engine revs? And, perhaps you should expect to replace it every 5 years or so?

I think both starter motors and alternators both have a lot of work to do and, they are 'taken for granted' and not thought of as part of the whole engine and, adjusted. I doubt very many Mechanics would know how to balance the electrics, or even think of it ever needing to be done between the battery and alternator.

stay safe

babybear

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#21
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Re: Why do Starter Motor & Alternators burnt too quickly?

09/09/2008 3:21 PM

A starter is a very intermittent duty device. Running it at full load will kill it fast. A forklift that takes longer to start and that it started too frequently, possibly due to a 'green' initiative, can kill a starter early. That said, in normal use a starter should last for 2 or more years. An alternator is a continuous duty device and should last 5 year or more. The permanent magnet types last the longest. A battery that takes a continuing large current will lose water (unless it has combining caps), and will lead to a shorter life of an alternator. I get the impression that these parts are wearing out in months, and all things are suspect, fiddles, china parts, bad rebuilds with cheap diodes etc. http://www.allaboutcircuits.com/vol_6/chpt_4/8.html

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#31

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 6:37 AM

Hello Hubert and welcome to the CR4 forum. I think you have just told us the answer to your vexing problem.

As we all know, alternators and starter motors work at different times in the vehicle operation, but you say both are wearing out. You also say that you are in the cement business. (That's the big clue, I think)

In automotive industry, we use dry cement powder in dust tests as it's very fine particles are able to penetrate EVERYWHERE and they are also very abrasive.

In the cement industry, your starters and alternators are in an environment that could cause dust to build up on most surfaces and cause accelerated wear plus additional drag/friction on most of the moving parts.

Suggestion : Can you find any "sealed" starter motors and alternators? (So that no dust can enter amongst the windings, gears and commutators.) I know that in the coal mines there were sealed starters and alternators on diesel powered underground equipment, but that was for flameproof conditions.

Also on many large farming tractors, the starter is sealed unit. (I would presume that is to stop dust lodging into the stationary parts while the machine is being operated.)

There are some more ideas for you.

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#34
In reply to #31

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 9:40 AM

thanksJust an Engineer,

you gave a top advise. i am operating in a cement production factory ( multi-billion project). The enviroment is always dusty. Assumption for sealed Alternators and Starter Motors is another great option. I will look more into these option..thanks alto, Hubert

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#35
In reply to #31

Re: Why do Starter Motor & Alternators burnt too quickly?

09/10/2008 1:04 PM

I agree that dust could be the culprit. The failure rate increase with the change of the mechanic may not be related to the new mechanic doing something wrong, but perhps the prior mechanic was doing something extra. Is there a way to contact the old mechanic about this problem? Perhaps if you put a few $$ his way he would reveal a few secrets.

Perhaps the old mechanic was treating the bearings with a higher fill of grease or was some how sealing the housings with silicone seal or sealing off openings with tape.

If we knew more about what was failing in the alternators and starters, we could make a better guess.

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#46
In reply to #35

Re: Why do Starter Motor & Alternators burnt too quickly?

09/18/2008 5:18 PM

hello shave,

that is called the "key man principle". have seen it in many companies. someone makes sure that the equipment goes out right. doesn't do it by the book, just makes it right. when he leaves, chaos. new guys try to do it by the book, and nothing works.

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#38

Re: Why do Starter Motor & Alternators burnt too quickly?

09/14/2008 3:15 AM

Insufficient information! Why was the mechanic hired? To replace another? To meet a growing problem with breakdowns? By what measure are you seeing yourself as having a problem? You say most of the forklifts and truck...what percentage of each would be "most"? And what is the size of your forklift and truck fleet, respectively. What was the frequency of such failures before the new hire? Was he unemployed or "stolen" when from another firm when you hired him? Is this mechanic charged both with troubleshooting and performing the repair? Has your firm instituted procedures similar to mechanic shops--as it should--whereby

  1. A trouble shooting check sheet is prepared for every job?
  2. Work orders must be submitted and signed off (by management) before any repair above a certain $amount proceeds forward?

Without such info there's little anyone can say to answer you question...without confusing your even further. And without maintaining a consistent authorization process and work record documentation, there's little you can do to either audit work performance or spot trends that indicate troublesome patterns and trends.

BTW, starters and alternators do not typically burn out quickly...until they burn out. So a sudden trend of multiple problems of that nature should be a cause for concern, you are right about that. However, it does not necessarily implicate the mechanic...if other employees also have access both the truck and forklifts...whether as operators or as mechanics. If you have multiple mechanics...I would suggest you make sure that the work is distributed among them...even switching mechanics in mid job from one equipment to another. The point of this will be...in case you new mechanic is being sabotaged (set up) by other employees...say, out of concern for personal job security.

CA

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#39
In reply to #38

Re: Why do Starter Motor & Alternators burnt too quickly?

09/14/2008 5:33 AM

Thank you very much Guest for the Critical, helpful information....for your information there were 2 mechanics. But both re-signed, and we got only 1 mechanic. Thank you. I guess you are very correct that i havent given enough information. however, everybody is very helpful in giving his view/opinion. to answer your concern. Well i have 2 x 3.5tone Komatsu forklift Model FD35t-7, these both have experienced alternator regulator burnt out and starter motor problem. I have a prime mover Nissan UD truck starter motor problem, whereby the Inching drive is slipping. This truck model is W-CW540GNT. there are others. i'd say 60% of my equipment.Hey, also we didnt steal the mechanic. We employed him ,but he lacks electrical knowledge, that whats worrying enough.

thank you much.

Hubert

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#40
In reply to #39

Re: Why do Starter Motor & Alternators burnt too quickly?

09/14/2008 7:02 AM

I think that you have an environmental problem with the dust, as mentioned already.

When the trucks were new, the slip rings (alternator) and the commutator (starter) were brand new and of full thickness. The refurbed items had probably half the possible wear already, good enough for refurb re usage, but not good enough for you.

You may have had extra heavy brush wear and earlier replacement of bruses may have kept the problem from occurring in the first place, it just depends on exactly which "bit" is actually wearing out first!!

I would say go with the refurbed units, but do 2 things, 1) put a pieces of fleece filter over the air holes (using long tiewraps), the same as used in air filters, this will allow the alternator still to get cooling air, but will trap the dust. replace when dirty. Or use a small fan, to blow properly filtered air under slight pressure through the units, thereby stopping the ingress of dust. 2) replace brushes at planned regular intervals, your mechanic should be capable of doing that.....but if the slip rings or commutator are wearing fast, then only the first alternative will bring any help for the problem....

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#41
In reply to #39

Re: Why do Starter Motor & Alternators burnt too quickly?

09/14/2008 2:16 PM

Hello again,

First let me say, that "stealing" an employee is just a part of the business vernacular, and not a pejorative term, here in the US. With most corporations, the preference is to hire (steal away in the sardonic sense) applicants who are already presently employed, whereas an unemployed applicant is generally deemed unemployable...unless there's no other hiring choice. It least that's largely the case with salaried (annually paid) employees...and may be less so with wage earners, especially with those in which there is steady turn-over...such mechanics. That said...a few more words along the business lines I mentioned before (the other guys seem to be covering the technical aspects pretty well...and (depending on you location in Oceania) I would add salt/salt air in addition to dust/sand.

Your OP suggested--I don't think you necessarily meant it that way--that the problems were arising after the new mechanic got his hands on the equipment, as opposed to "in the field"...although either is a situation that is hard to envision. In any event--and especially so since you know (knew?) of the mechanic's (and most mechanics') weakness in electrical--you are not in a position to cast blame on him without direct (eye witness) evidence...and perhaps not even then.

Going back to the "steal" idea--but this time in the sense of stealing one's self away (as in leaving one employer to take a position with another)--you said your former two mechanics resigned, but did not elaborate on the circumstances, or on whether they left together or in short order one after the other. I'm envisioning a case where they might have left you and gone to work at another firm for reasons unknown to you--perhaps because of a private grievance of some kind--but also (one or both) might have harbored some concern as to being welcomed back if things did not go well at the new employment. In such a case, it is not beyond possibility that a little sabotage before departure, whether out of spite or to inflate the importance of their loss as compared with your new hire, could have been inflicted as their parting gift to you. So, it seems you are probably in a position where you must "bite the bullet" and be prepared to absorb unplanned maintenance expenses. Because you have no electrical guy, you might be well advised to call one in temporarily, or take the machines you can spare to an electric shop, for the purpose of more or less gradually doing a full electric checkout of your fleet. The thinking is, that although it will be costly, it could be less costly in the long run in terms of untimely breakdowns and loss of equipment availability, and the revenue losses thereby.

In the meantime, you should also institute a hard and fast rule: that no work, electrical or otherwise, be performed on the equipment until after the battery ground cable is disconnected from battery. For one, this serves in the future to prevent accidental damage to the electrical subsystems with which you are presently experiencing difficulties.

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#42

Re: Why do Starter Motor & Alternators burnt at the same times?

09/14/2008 2:50 PM

Alternators and starters...and at the same times? Hmm!

Is there any chance, any pattern - say on long shifts or when starting shifts without topping off fuel - that operators are running the fuel tanks dry; and then getting lazy and using starter keys, starter batteries, and starter motors to (electrically) propel to the fueling station?

Did you ever consider mounting a small, 1-gal gas can on each unit to make sure this doesn't happen?

Just one 2-cents worth.

UG

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#43
In reply to #42

Re: Why do Starter Motor & Alternators burnt at the same times?

09/14/2008 6:41 PM

Thanks, thats a that scenario. yes, you are partly correct because sometimes the instance of tank being dry do really occurs. as was the case for the Prime Mover Nissan startor motor. i'll get to make sure that fuel is always, re-filled prior to every shifts. Thanks very much, hubert

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#44

Re: Why do Starter Motor & Alternators burnt too quickly?

09/15/2008 7:30 PM

It could be something as simple as bad battery connections.If the batteries have bad connections the alternator is overworked and with low amperage the starters don't work properly.Could also be batteries are getting bad.Although peculiar that they would all go at the same time.Your mechanic needs to clean all connections,test batteries if he has a battery load tester or his brother n law or best friend owns the parts house.Just a little humor LOL God Bless !!

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#45

Re: Why do Starter Motor & Alternators burnt too quickly?

09/15/2008 11:24 PM

I would like to add some things for you to think about.

  • First you mentioned that you have booster-jumper cables for times when batteries are dead. Why should you ever have dead batteries on a 24-7 vehicle.Load test your batteries. If you have any question of the batteries, replace them with the biggest best batteries that will fit. Maintain same voltage, add cranking amps.
  • Batteries are no better than the cables that connect them. Inspect both ends of both cables. If you have any questions about any cables, replace them with #2 or larger cables. NO replacement cable ends permitted.
  • You mentioned that the vehicles sometimes run out of fuel. This is never to be allowed to happen. At each shift change have the oncoming operator get a gas can and fill the vehicle. Have the off-going operator bring the empty can back. Or at lunch break, have the operator drive the vehicle to the fuel site. YOU need to make this change happen. The operators don't want to do this.
  • There was a suggestion to use felt to keep dust out of the alternator. I would suggest that instead use air conditioning filter material. Fair filtration, and low restriction. Cover the radiator and any other area that draws air into the engine area. At oil changes, have the mechanic wash these filters out with water, and replace.

I hope this helps you. Good luck.

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