MEP 003A troubles

[CUCV_Fan]

Been a reader mostly I have been bitten by the bug I saw a MEP003a and trailer for 750.00 on CL so I went there and it was pouring rain out the genny did not have a throttle cable but i made the guy fire it up it ran but unfortunately I did not check any of the guages before i made the sale. so I got it home thanks to all of you here found the parts i needed at delks I got a throttle cable and the gov spring new batteries just been taking my time with it. fired it up for the first time last night and the guages show nothing. I have been through all the youtube vids every one on youtube fires up and shows some type of output on the guages - the only guage that shows anything is the battery charge guage. I have found so much that seems like this was a parts machine wallerd out bolts missing bolts loose everything lol it seems I just wanted to know if you feel its worth it to keep working on it, am i missing something when i start it up a switch or breaker that needs to be checked or should i just enjoy the trailer that came with it and look for one that is in working condition. I must say that this is a very addicting hobby for me and I am really enjoying it. any words of wisdom for a newb 003a owner im sorta discourgaged at this point not knowing where best to put the cash.

Kind regards

Bill

 

[Isaac-1]

Have you tried reflashing the field by turning the switch back to the start position while it is running? There is a protection relay system that should keep the starter from engaging while the engine is running and only flash the field. This could be the easiest fix, we can go from there, it may be something relatively easy to fix, or not, you just need to take it a step at a time and see..

Ike

p.s. try plugging something into the onboard outlets and see if it is only an instrumentation issue (unlikely, but worth checking to see if it is really making power)

 

[coyotegray]

First off, $750 is a great price.!! Does it have a ASK kit..?
Do you have the throttle turned down..? It should not be idled..


If you put a meter on the utility outlet do you get a reading..?

I'm much better with the engine side than the gen side. There are several very knowledgeable people around here that I'm sure will help out..


Andy..

 

[CUCV_Fan]

No ASK kit - I did plug in a grinder to the onboard outlets nothing I will try the flash idea this evening. I checked all the wired coming out of the gen head nothing seems to be broken, or bare the panel light works but im not sure if that is working from the batteries or the machine. My fear is a bad gen head. I would think that maybe at least one of the out put guages would work.

Thanks for the replies.

Bill

 

[Isaac-1]

After posting my initial message, I also thought about the idling issue since you had a throttle cable issue, these units are not designed to idle EVER, they are designed to be started then immediately throttle up to 1800 rpms, idling for more than a handful of seconds will burn out the voltage regulator. (this can be fixed though, usually it is just one transistor that goes)

Ike

p.s. when you try to reflash the field watch the ac voltage gauge, see if it spikes up then drops back off, if so it is usually a sign of either a bad voltage regulator or rotating rectifier, both can be fixed

 

[Speddmon]

No ASK kit - I did plug in a grinder to the onboard outlets nothing I will try the flash idea this evening. I checked all the wired coming out of the gen head nothing seems to be broken, or bare the panel light works but im not sure if that is working from the batteries or the machine. My fear is a bad gen head. I would think that maybe at least one of the out put guages would work.

Thanks for the replies.

Bill

There is pretty much nothing on these machines that can't be fixed with a little time and patients. First off, welcome to the site and from the sounds of it, you got a fair deal, if we can get you producing power.

To start with, have you read through the -12 TM? This is the operators TM, and explains a lot of the things you'll need to know about the operation of the set. If you have not read it, I suggest you go to the top of the screen and click on the resourced tab, and then click the "Technical Manuals" link. This will take you to the old site where the TM's are located. I believe the ones you need are on the 5th page, they are TM 5-6115-585-12, TM 5-6115-585-24P and TM 5-6115-585-34. They are the operators manual, the parts manual and the maintenance manual in that order.

Next, when you start the set, as Isaac mentioned, DO NOT leave the set idle...EVER!! If your governor and throttle cable are set correctly, you should have the throttle pulled out about 3/4" when it's running at speed. This is a good starting point since you are getting no output to reference the frequency by. 1800 RPM's equates to 60 Hz. Once you get it producing power and showing the Hz, set it to 60 Hz and just don't touch the throttle again. That way when you shut it down it was set for 60 Hz and it will go right to 60 Hz when you start it up again.

On the bottom right side of the control panel is the amp/volts selection switch. make sure you have it set in the right position. It sets the volt meter and % load meter to read certain "legs" of the output depending on the setting of the reconnection switch. If you have it set for the wrong setting, you will not see anything on the volt meter.

Since you have already plugged something into the convenience outlet and got nothing, make sure the small breaker beside the outlet is pushed in. That breaker protects the outlet, while the large breaker protects the main output lugs. If that breaker was already reset (pushed in), then the next thing to try is the manual field flash that Isaac mentioned. This may get you producing power again. If it has been a long time since that set was used, it is possible that there will not be enough residual magnetism left in the generator head to get it making power on it's own.

If that doesn't get you going, the -34 TM has a good troubleshooting section for this kind of problem. And tells you how to troubleshoot the rotating diodes and the VR. I have 2 voltage regulators to repair right now, and I am in the process of making a permanent test station for them. But it is pretty easy to put one together, as long as you have a variable AC voltage source. If the troubleshooting section leads you to the VR I could check it out for you if you don't have the ability to make the test circuit yourself.

If the troubleshooting section gets to be too much for you, post up details of what you did and what's going on and we'll do all we can to help out.

Good Luck

 

[CUCV_Fan]

Ok first thank you very much for the info. I got the manauls I was missing 2 of them. A lot of missing info was found in the other manuals.. It appears that you are correct the Voltage regulator is shot. I did the field flash and nothing happened check the onboard outlets reset switch nothing. I know that the machine has idled before that is something that the man I got it from was doing with it. I did not even know that the system was that sensitive to idle myself. I will give Delks a call tomorrow and see what another regulator is going to run me. Again my thanks for now I'm going to go through the manauls and see what else I can find that may need to be done.

Kind Regards,

Bill

 

[steelandcanvas]

I wanted to thank Speedmon, Issac-1, Coyotegray, and others who make this Auxilliary Equipment thread so helpful and interesting.

 

[Speddmon]

Ok first thank you very much for the info. I got the manauls I was missing 2 of them. A lot of missing info was found in the other manuals.. It appears that you are correct the Voltage regulator is shot. I did the field flash and nothing happened check the onboard outlets reset switch nothing. I know that the machine has idled before that is something that the man I got it from was doing with it. I did not even know that the system was that sensitive to idle myself. I will give Delks a call tomorrow and see what another regulator is going to run me. Again my thanks for now I'm going to go through the manauls and see what else I can find that may need to be done.

Kind Regards,

Bill

Bill,

Please let us know what Delk's says about the VR. I am afraid that it will not be cheap. If it's more than you are wanting to spend, shoot me a PM and we'll discuss repairing your old one.

Before you condemn the VR as being the culprit, look inside the output box on the side of the set. Pull the front cover off and look at the back wall of the box, under the main output lugs behind the main breaker. There you will find the bridge rectifier board. If the guy you got it from was idling the engine a lot, there is a possibility that the bridge board got fried. I would hate to see you spend money on a new used VR and find out that it still didn't fix your problem. There may also other things that could possibly be the problem, I'll have to look through the TM to be sure.

 

[Isaac-1]

Like Speddmon said, before assuming it is the voltage regulator I would rule out the rotating rectifier, I am not sure how had it is to access on the MEP-003, however an easy test to see if your problem is the VR is to manually flash the field with a small 9-12V battery. You do this by removing the F- and F+ leads from the generator to the voltage regulator and while running momentarily touch them to their respective +/- battery terminals, you should see the voltage spike to a ballpark of its correct output. If it works the VR is likely the problem, if it does nothing or goes to some low voltage (under about 50 volts) the rotating rectifier of the field windings are then suspect.

google generator field flashing with battery

Ike

p.s. You can buy replacement power diodes online from digi-key or maybe mouser for a few dollars each

 

[WARWAG]

Any Updates?

 

[H500D]

Mep 003a

Hello does any body know what the five small wires going to the main braker do? Thanks in advance

 

[Speddmon]

There should be 6 small wires going to the main breaker. The main breaker has two different trip ratings. The main rating is 50 amps for the MEP-002a and 100 amps for the MEP-003a (two different breakers). The secondary rating (for the small wires) is 0.75 amps. That trip rating basically protects the control circuits from an overload condition if something would short out or become damaged. Either trip setting will trip the main breaker and open the output.

 

[H500D]

thank you very much for the explaintion, it helps me more understand my machine thanks again