NO Voltage or HZ reading on meters

I went out and started the 002 to let it run for a little this morning. I went back after about a half hour and noticed that I had a minor oil leak from the canister seal. I shut it down and replaced the seal. When I started it back up the leak was worse so I had to shut it back down and fix that. At that point I was down too low on oil so I added some. When I restarted it the voltage and Hz jumped up and dropped completely off after about 15 seconds. I shut it down and repeated start up and had the same result. I shut it back down, said a prayer and started it up and they have held now for about 15 minutes.

Do I need to be concerned?

What might have caused it to do that?

Thanks
Bob

Maybe you didn't quite flash the field long enough on those two start-ups??

Since it did seem to start to build voltage from the field flash I suspect you may have a problem in your voltage regulation system, It could be something very simple like a loose wire or a bad connection in the push to reset AC breaker down by the front outlet (if it happens again try tripping and resetting the push to reset breaker a few times, they tend to get dirty), or it may be the AVR board, bridge diode going bad, etc. If it had failed to build initial voltage I would say you just were not holding the switch in the start position long enough.

Ike

Thanks! It ran for another half 40 minutes and held voltage the the hz stayed right on 60.

After changing the glow plugs this evening I started it up to be sure it was going to run okay. It took right off but the voltage and hz dropped to zero. I restarted it 3 times. On the first two of those I noticed that both voltage and hz spiked clear up until I left go of the start button and then dropped to 0. The third time it started and both were right on the money. I had it shut down for about 30 minutes to finish buttoning everything up and restarted and it was normal. I hate intermittent problems.

If anyone has a specific area I need to look please let me know.

While gauges at zero, did you put a meter on the convenience outlet to see what was really happening?
Jerry

storeman said:

While gauges at zero, did you put a meter on the convenience outlet to see what was really happening?
Jerry

Click to expand...

Yes, no voltage

" push to reset AC breaker".......this is what happened to me with one of our Mep-002's. I overlooked the breaker, checked each circuit per schematic......and I forgot to check the breaker. Sometimes it's as simple as that.

Neophyte said:

" push to reset AC breaker".......this is what happened to me with one of our Mep-002's. I overlooked the breaker, checked each circuit per schematic......and I forgot to check the breaker. Sometimes it's as simple as that.

Click to expand...

I did check it. Actually pulled it and reset with no results.

There was a good discussion about field flashing a few weeks ago on here. Different problem IIRC, but it should get you going in the right direction. Take a look at that bridge rectifier board inside the back bottom of the ac re-connection box.

I was just messing a little and noticed something.

Is it possible that the start switch could be the problem? Here is why I ask. It starts and the voltage and hz both spike and drop as soon as I let go of the start switch. If I turn the start switch back toward start about half way voltage goes to 220 and hz to 60.

Sounds like you may be on to something, switches can go bad.

If that is the case where would I find a switch?

I had to replace a faulty switch. It was doing something like what you described.

I bought a used take out from Delk's. (google delk's surplus).

They guaranteed(I asked) it would be good, or they would send a free replacement.

That solved my issue.

I called Delk's. He suggested that it was probably not the switch. Said when I am turning it I am flashing again.

He said one of three things. Regulator Board, CTV1 or the Reactor and more than likely the Regulator.

Another question. Seems I read somewhere that you are not to run these without a load on them. When I have had it running I have stuff in the convenience outputs and do not turn the main breaker on. Could I have ruined the board by running it without enough load?

Where is a good place to get a board at a decent price?

ETA: Can I fix the board I have?

Usually when the AVR board dies the voltage goes high on these units, no voltage is more likely associated with either a bad reactor or more likely a bad rotating diode. Just to clear things up here in your description, is the voltage dropping off as soon as you release the start switch, or is it holding for some seconds then dropping off? Your initial description made it sound like it is holding for some seconds.

Ike

Isaac-1 said:

Usually when the AVR board dies the voltage goes high on these units, no voltage is more likely associated with either a bad reactor or more likely a bad rotating diode. Just to clear things up here in your description, is the voltage dropping off as soon as you release the start switch, or is it holding for some seconds then dropping off? Your initial description made it sound like it is holding for some seconds.

Ike

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Sorry! It drops immediately when I release the start knob. If I turn it back to start without turning it off the meters both go to normal. I don't completely understand the whole thing but it seems that it is not "holding the flash" if that makes sense. According to the guy at derks when I do that I am flashing it again. As soon as I let go it is gone again.

Dropping off upon release from the start switch does sound to me like a problem in the voltage regulation system. In my experience the most common cause of this is bad rotating rectifier diodes, on the one hand they are cheap, on the other they can be a bit of a pain to get to and replace. There are step by step diagnosis procedures in the the TM's ( I think in the -34 manual)

Ike

Isaac-1 said:

Dropping off upon release from the start switch does sound to me like a problem in the voltage regulation system. In my experience the most common cause of this is bad rotating rectifier diodes, on the one hand they are cheap, on the other they can be a bit of a pain to get to and replace. There are step by step diagnosis procedures in the the TM's ( I think in the -34 manual)

Ike

Click to expand...

So you are saying to start with the VR?

I am not a super mechanic but if I need to I can probably figure out how to check the diodes but if you feel it is the VR I may just change that out.

Any good leads on where to get one of them?

The other question I asked above was "Did I create the problem by not putting enough load on it when running it?"

It had worked fine until I changed the glow plugs. I know that had nothing to do with it but it seems strange it went all at once. At least to me.

I know of no reason running this generator without load would hurt anything. Larger water cooled diesels can develop excessive deposits in their exhaust systems when run lightly loaded for long periods.