Hey guy i am facing this issue that my pc300 didnt start with 24 v it crank but didnt start and while i put one more battery thn it start i check self it is found ok, plz help me
Electrical is something I have experience with. I would recommend NOT running the system at 36V. This can cause quite a problem for a variety of systems, including the starter windings. I would first verify the batteries are working correctly by removing them and load testing them. A battery should be able to carry 1/2 the CCA rating in amps for 3-5sec and a voltage drop of about 15-20% and return to full voltage when load is removed. Example is 1000CCA, 12V bat, should take 500A load for 3-5sec and pull down to 10-10.5V. You should also test the current draw from your starter. It is best to know how much current it should draw. An out of spec current does NOT always mean a problem with the starter but is a helpful tool. Low current could be a weak engine, bad brushes in starter, bad windings in starter, or compression leakage in the engine somehow. High current could also be bad brushes or windings, starter loose or binding up, or engine problems causing high start torque. A typical field test on the starter is to remove starter and reconnect to power and see what the no load current is when tested for a could seconds. If current is still very high, you have a starter problem. High temp at starter when cranking for short periods also indicates a starter issue. ADD: during cranking, it is important to check all terminals and cables after cranking for heat. You may have a little heat but anything that gets overly warm or even HOT is your problem. When current hits high resistance via poor connection broken wires, etc, will cause heat. Think in terms of the element in a light bulb. It is important to use a "DC" current meter for these tests. They are not as common as AC but my Fluke 337 does this perfectly. Another important test is to set your meter to DC volts and connect one lead to the lug on the starter, the other on the POS lead at the battery, and crank it. This value will be zero until cranking, and then will show you the voltage loss through the cabling to the starter. This should be minimal. Repeat for the ground cable to chassis.
Thanx for ur prompt reply mean while i am sure that it is not n issue of battery as i have put 2 new battery but the problem continues rest self is all ok as i have opened it and check for brushes n all so i am sure of tht now wht else it can be is it the governor ?
If you think all electrics are good, you need to determine what the spec is for cranking speed and test that. This is easily done with an IR tach tester and a little piece of reflective tape. Diesels need the proper cranking speed or they won't start. After cranking, observe exhaust for white or black smoke or smell after cranking for fuel odor. If engine is a glow plug engine, that needs tested. No glow, no start. Check air cleaner. Fuel needs air. As well, engine compression may need tested. I can guarantee you that pushing the machine to 36V just to start means something is wrong and should not be utilized. Also, if you do not test for voltage at the start when starting, you are still guessing. New batteries do not fix a cable problem. Seen it many times. Just put meter on POS lug and its chassis and crank it. Tell me what that voltage is.
Ok will let u know by tomorrow i will put one end of meter to battery and other to starter with dc and crank it right?
Second that. It will work for such a short period of time that it will be more expensive than new starter, batteries and all. Yes, measure the voltage drop from one end of the cable to the other, the battery terminal to the starter terminal and crank it. Then repeat for the ground (earth?)cable, then repeat for the starter terminal to ground to get cranking voltage at the starter. Then feel the starter and all the cable connections to see if anything is warm.
As a very quick test, you can just put one lead on the POS lug of the starter, the other on the Chassis of the starter. Record voltage when cranking. Do the same with meter leads on the POS and NEG at the battery. The reason is the batteries will certainly pull down under starting load but we need to compare what the starter is getting vs what the batts are pulling down to. If batts pull down to 21V but starter is seeing 15V, you have voltage loss and use the methods I and Delmer mentioned to chase that down. I just did this very thing a week ago on my truck only to find the buss bar INSIDE the battery was toast. localize heating lead me right to the problem. A slick trick I use in electrical and electronics repair, though no cheap, is the nifty FLIR camera. I could literally watch ALL your cables at one time and see what gets hot instantly. I use this a lot to repair electronics by finding hot spots in areas that should not be hot. Much safer than touching things.
Another item to check is crank it with the 24V for your voltage test and get your digital testers out, touch the cables near the ends, they shouldn't be more than just barely warm, I had a couple bad crimps on a 644E loader, replaced one cable and one cable end to remove 3 dodgy connections that were getting hot and the slow cranking dissapeared. If the voltage drop is large with good batteries, your starter may be dragging ass, have it tested.
Ok i will when i reach my site
The checks stated above are prudent but you need to supply more information. You mention that the engine turned over but didn't start. That does not indicate a starter problem!!! Hooking up 36 volts to start the engine will fry the computer and blow a pack of diodes in short order. What Dash series is the machine? Maybe a serial number will give us that.
Guys lil request as i am very poor in electronics can u tell me point wise all checks then i will do it in report u plz elaborate thnx in advance
Search images for "battery cranking voltage test" it will bring up lots of diagrams. You want to test Postive to Negative battery terminal, resting and cranking. Positive battery terminal to starter terminal cranking. Negative terminal to starter body cranking. Starter terminal to starter body cranking. Some alligator clips and test leads make this safer and easier.
Guys i have done following checkes 1. One lead to the lug on the starter and other on the pos kead of battery while cranking voltage : 1V 2. Pos lug battery and chasis : 20V 3. Battery terminal to starter while cranking: 1V 4.starter terminal to ground : 19V 5. Pos lug of the starter and chasis of the starter: 19V 6. Pos of battery and negetive of battery while cranking : 21 V These are all my finding suggest further
I would like to know the static no-load voltage on the batteries but it sounds like you are either hitting the batteries with some serious load or they are not fully charged. The voltage drop would indicate about max cranking amps from the batteries. However, things seem in order for the most part on your tests. I might like to see better but probably not the cause of your issues. The next tests that I really need is amperage in the POS cable during cranking, AND the cranking speed of the engine. Trust me, if you don't have a tach, they can be quite handy in the toolbox to own. This is sounding more like a glow plug problem. What engine? Glow plug engine?
Did anything feel warm? 21V at the batteries and 19V at the starter seems like the cables and connections are fine. I'd pull the starter off and bring it to a starter/alternator rebuilder. If you can't find a starter rebuilder, then ask an electric motor repair shop, or automobile mechanic where they suggest to get a starter tested and rebuilt. Not saying the amperage and tach aren't important. Just a different way to go about it.
He mentioned something about inspecting the starter brushes but there is also coils in there. I agree the starter should be inspected fully. However, I think Delmer and I are in the same camp, just looking at it differently. The cranking speed just verifies the engine is cranking correctly. However, anyone familiar with their machine would know if it is cranking like it always has or is slow. I tend to think the starting system is working and this might be a glow plug issue or something minor with the engine such as not enough power to the shut off solenoid or something simple. All things which we are chasing tails about because the simple things have not been verified. Crank speed on a diesel is important because the rate of compression of air causes heating of the air charge thus causing combustion. You have to get over the hump thus why glow plugs or air charge heaters are used. I think we just need more details here.
Starter checked from rebuilder he says it is fine company service engineer doubt tht may be pump problem
Hydraulic pump problem? could be why it's cranking slow. Injection pump problem? not getting any fuel injected? that makes it tough to start too. Is there any smoke/mist coming out the exhaust when it's cranking? What elevation is this working at? what's the temperature?
Injection pum FIP well smoke n all r perfect temperatures r normal ! Is thr b a problem with solenoid ?
In English please?
Fuel injection pump is the doubt and i have checked all temperature and smoke every thing seems to me normal. I suspect solenoid valve
NO, you don't get smoke or raw fuel in the exhaust if the solenoid is not functioning. It will stop all fuel flow instantly. If engine will run normally once started, it probably is not the injection pump. Try starting without the air cleaner. Sounds like you need to follow my advice and determine what the cranking speed is on the engine. This will tell you if you are chasing an engine or electrical or hydro pump problem.
All this is just wasted typing until you know which machine is being worked on. Komatsu engines have such high injection pressures that they start instantly when compression is correct and fuel gets there at the right time. Basically if the engine makes one turn it will start. Now there are plenty of other places to look for a turn but no start but we have to know what is being worked on.
Ok guys im back with further updates Well first of engine model number is SAA6D11 4E-2 Serial number : 26831868 Today i started with 36 V and then run that machine for 5 min then i remove extra battery and tried starting with 24V it started but it took almost 4 revolution of crank weather in 36V with only 2 rev it started. Then i tried out machine after 1 hr and started it with 24V it satrted with little bit more cranking Now my point is what is the problem then. I will try out tomorrow again .
Let me try this another way....... Lets say you have a 24V starter. That starter under full load pulls 300A. That will require a coil resistance of .08ohms. When I apply 36V to that coil, the formula is V=I/R or 36/.08= 450A!!!!!! As well, the power used at 24V is 24*300 = 7.2KW, and now 36*450 = 16.2KW!!!!! Are you getting it yet? You ARE going to burn out that starter, I guarantee it!!! Fix your problem the right way. If it won't start on 24V, fix the issue, not make another one. You still have not tested the cranking speed which will indicate a LOT here. Or keep throwing 36V to it and then post all your error codes for blown light bulbs, diodes, regulator, solenoids, etc.
Yes i can understand wht u want to tell me thts why i am no more starting it with 36v and about the cranking speed i dont have tech here its on remote location but wht i obsereve is that it take 3-4 revolution in 24v to start
What you are describing is normal to me. If it starts and runs fine on 24 volt then what is your problem.
I have to check today again coz yesterday i initially strted it with 36v and then i tried with 24v it was wroking now today i wll try directly with 24v n will post the result soon
Hello guys so here is the conclusion i tried directtly with 24V now it is starting perfectly still wht was d problem is unknown to me what i did was removed solenoid connection the one before pump and there was some moisture i cleared it and again pug d connection thats it!