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so does the engine run and shut down correctly?
I am on and off, so no guarantees on quick replies
I am on and off, so no guarantees on quick replies
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Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!
MEP-804a no start (no power to fuel shutoff solenoid), it DID run recently.
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TacMac2012
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It didn't, but now it does start/run correctly, it MAY have been related to low voltage, I have been in the process of charging the batteries and I guess they were strong enough to turn it over but was not enough voltage to power the other stuff.
Just no readings on Hz or voltage gauges now.
Just no readings on Hz or voltage gauges now.
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Do you get voltage if you hold it in "start" after its running?
Post 1000, and its my birthday. Woohoo!!
Post 1000, and its my birthday. Woohoo!!
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Happy Birthday Chris!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
OK, NewEra. Is there a fuse next to the volt regulator? If so, have you tested it?
Like I said before, the hertz meter will not read if the main gen produces no voltage.
If the fuse is good, then start up the set, hold S-1 the up position, and see if you have 24 volts at the Fuse next to the volt reg. You can do this by using the J3 Diagnostic canon plug. Insert your probes into pins F & J. Pin F is +, and pin J is neg. You should get 24 volts, as long as you hold up S-1. This is the excitation circuit.
The fuse should be FU2, but will not be on your schematic. Its inline with A1, pin 1 and G1, (main gen) pin F1. At some point in time someone will get around to fixing the schematic, after all, the MWO is 10-12 years old by now, if not older.
OK, NewEra. Is there a fuse next to the volt regulator? If so, have you tested it?
Like I said before, the hertz meter will not read if the main gen produces no voltage.
If the fuse is good, then start up the set, hold S-1 the up position, and see if you have 24 volts at the Fuse next to the volt reg. You can do this by using the J3 Diagnostic canon plug. Insert your probes into pins F & J. Pin F is +, and pin J is neg. You should get 24 volts, as long as you hold up S-1. This is the excitation circuit.
The fuse should be FU2, but will not be on your schematic. Its inline with A1, pin 1 and G1, (main gen) pin F1. At some point in time someone will get around to fixing the schematic, after all, the MWO is 10-12 years old by now, if not older.
TacMac2012
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TacMac2012
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TacMac2012
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Only getting about 9 volts between F & J
TacMac2012
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I saw somewhere in my searching that someone mentioned much better wiring diagrams are located somewhere, the ones in the manuals are less than great, and honestly, make little sense to me. Of course now I can't find the mention of those diagrams...
TacMac2012
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So I did step H and got 8 volts
step J i got about 7 volts (AC) whether the switch was turned or not
and step i, the numbers didn't match what the TM says, but they did vary
Stupid thing is, step M says if the tests I completed showed up as they "should" in each step that the box is bad. It makes me seem that in the military this would be one of those throw parts until it's fixed situations. So if the tests checked as they 'should', does that mean it is good if the tests come up with ANY other number than what is stated? Makes zero sense to me...
And obviously step J is going to read zero volts, if it was making power I don't think there would be much need in doing the test...
step J i got about 7 volts (AC) whether the switch was turned or not
and step i, the numbers didn't match what the TM says, but they did vary
Stupid thing is, step M says if the tests I completed showed up as they "should" in each step that the box is bad. It makes me seem that in the military this would be one of those throw parts until it's fixed situations. So if the tests checked as they 'should', does that mean it is good if the tests come up with ANY other number than what is stated? Makes zero sense to me...
And obviously step J is going to read zero volts, if it was making power I don't think there would be much need in doing the test...
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TacMac2012
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I messed with it some more yesterday, I would think that if I am only getting 9-10 volts going to the excitation circuit, that may be the issue. I have looked at the schematic and can't figure out where the AC Volatage regulator gets it's 24v supplied from, and I would assume it needs 24v to be able to send out 24v. I looked at K14, the overspeed relay, it does NOT energize no matter what I do, now it may only energize when there is an overspeed situation, I am not sure.
I do have a low voltage light on on the warning light panel, not sure if that will keep the overspeed relay from energizing or not. Any help much appreciated. If anyone knows where a good wiring diagram is that would be great, as the factory diagram doesn't show ALL the wires in the system.
I do have a low voltage light on on the warning light panel, not sure if that will keep the overspeed relay from energizing or not. Any help much appreciated. If anyone knows where a good wiring diagram is that would be great, as the factory diagram doesn't show ALL the wires in the system.
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Did yoy get your batteries fully charged or have it slaved. I remember an earlier thread on an 805b that said less than normal voltage can cause unusual faults
TacMac2012
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I do think the low batteries were the cause of the no-start, I thought the same about the no power but that doesn't seem to be the issue. Yesterday I had it slaved and also had a charger on one of the batteries on the generator. It had stopped charging the batteries but I figured out the 'battery charge' fuse was blown so I replaced it and it's charging again.
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What are you slaving from?
Get both batteries tip top, then start to troubleshoot.
Before you can troubleshoot the A1 AC volt regulator, you need to determine if you have a Libby or TRC volt regulator. since you performed the testing of the A1 sometime before, what type volt reg do you have. Did you download the Volt regulator information that in the manuals forum? And read it?
Get both batteries tip top, then start to troubleshoot.
Before you can troubleshoot the A1 AC volt regulator, you need to determine if you have a Libby or TRC volt regulator. since you performed the testing of the A1 sometime before, what type volt reg do you have. Did you download the Volt regulator information that in the manuals forum? And read it?
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TacMac2012
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Slaved off a HMMWV. With generator running/charging, HMMWV running/charging, this is after charging both gen batteries with a 12v charger it still does not produce power.
I honestly have never even looked at the TM section, that's one of those sections I have always overlooked. I did find the 804 manuals post (and the color coded one I was wanting!), but didn't see anything referring to specific voltage regulators.
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Perhaps you should look into the TM section here in SS.
Perhaps you should download all the TM's here for your gen set.
Perhaps you should also download a document that explains about the different AC volt regulators.
There are also several threads that might be of help.
If there is a color coded schematic, perhaps you might share with us.
If you read the TM's, the AC volt regulator test procedure, you will find that the TM's have a test procedure for the Libby Regulater and the TRC Regulater.
Perhaps you should download all the TM's here for your gen set.
Perhaps you should also download a document that explains about the different AC volt regulators.
There are also several threads that might be of help.
If there is a color coded schematic, perhaps you might share with us.
If you read the TM's, the AC volt regulator test procedure, you will find that the TM's have a test procedure for the Libby Regulater and the TRC Regulater.
TacMac2012
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I worded that wrong. I have never looked in that section before NOW.
Color coded wiring diagram is posted here (you actually posted it), but I did not see any manual about testing the voltage regulator. I have searched through many threads to no avail.
https://www.steelsoldiers.com/showthread.php?148936-All-the-TM-s-you-need-to-work-on-the-MEP-804A
Color coded wiring diagram is posted here (you actually posted it), but I did not see any manual about testing the voltage regulator. I have searched through many threads to no avail.
https://www.steelsoldiers.com/showthread.php?148936-All-the-TM-s-you-need-to-work-on-the-MEP-804A
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If you go to TM 9-6115-643-24, Chapter 4, pages 4-1 and 4-2, you will see that the manual shows test procedures for TWO different kinds of volt regulator. The manual also tells you that you can not MIX the components of the two systems.
There is no special manual for the testing of the regulator. I was referencing a document that lists the components of both types of voltage regulation systems. That is the only way to tell the difference between the systems. You need to see if you have one system, or the other. Not a mix of parts. LIBBY or TRC. THEN you know which test procedure you need to use for your regulator.
I just remembered that the document I referred to, is for the 805 and 806 gen set. As soon as I can get to my computer to look up the info, I will post a listing for the MEP-804A it. Thought I had already done that. But you can still look at your volt regulator for the part number and THAT'S the number to use for testing and adjusting.
There is no special manual for the testing of the regulator. I was referencing a document that lists the components of both types of voltage regulation systems. That is the only way to tell the difference between the systems. You need to see if you have one system, or the other. Not a mix of parts. LIBBY or TRC. THEN you know which test procedure you need to use for your regulator.
I just remembered that the document I referred to, is for the 805 and 806 gen set. As soon as I can get to my computer to look up the info, I will post a listing for the MEP-804A it. Thought I had already done that. But you can still look at your volt regulator for the part number and THAT'S the number to use for testing and adjusting.
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In the TM upload section, (and later in the Generator TM section) is a list of parts that make up the LIBBY and TRC Electronic Governor systems for the MEP-804A and MAP-804B. Before you test, adjust, or replace and of these parts, you need to insure that all the other parts are from the same manufacturer. Failures to do so, can result in the damage to you generator set. You can NOT mix parts between these systems.
TacMac2012
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It is a TRC. I will report back after I get a chance to look at the manual and test it. Thanks
TacMac2012
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I looked at the testing procedures again. What does not make sense to me is why the manual says "test this, the numbers (voltage, ohms, etc) SHOULD be in this range xx-xx. There are three 'tests', that all say the numbers SHOULD be in these ranges, then it says "If steps h,j,I are as indicated above the regulator is bad and should be replaced"
So, in my mind, those numbers that you "should" have are either numbers outside of the required range, or they worded the manual wrong. In step "J" it is a waste of time, because obviously if the generator is not making power there won't be AC voltage at the regulator. But since it says there SHOULD be voltage (and therefore making the regulator 'bad', does that mean a lack of voltage means it is 'good'?
I printed out the color coded diagram and am going to go out and try and figure out where the regulator gets it's 24v supplied to it, as I feel that may be the problem, if the FU1 is supposed to have 24v and it doesn't, it seems that might be the issue.
So, in my mind, those numbers that you "should" have are either numbers outside of the required range, or they worded the manual wrong. In step "J" it is a waste of time, because obviously if the generator is not making power there won't be AC voltage at the regulator. But since it says there SHOULD be voltage (and therefore making the regulator 'bad', does that mean a lack of voltage means it is 'good'?
I printed out the color coded diagram and am going to go out and try and figure out where the regulator gets it's 24v supplied to it, as I feel that may be the problem, if the FU1 is supposed to have 24v and it doesn't, it seems that might be the issue.