Problem with MEP004

viking1 · Mar 14, 2018

Hi Folks. I have an MEP004 with a white 4 cylinder diesel rewired single phase for backup power on my shop. I had someone else tear it down to rebuild the pump/injectors, as it was filling the crankcase with fuel and shutting down (although it runs great). Anyway the rebuilt parts are correctly back on, but now the issue is when I connect the batteries the engine immediately starts cranking (no matter what position the on/run/start switch is in). I disconnected the hot wire at the solenoid, but cant figure out that issue. Should I suspect a bad switch? It also wont start on diesel alone now (fires immediately on ether), although it started and ran for about 1 minute initially. I couldn't get the engine to shut off with the switch, so I pulled the fuel line to shut it down (shutoff didn't seem to do anything either, but I guess that's normal?). The fuel pumps work normally with either the battle station switch or with the main switch in the "start" position (doesn't run on the other 2). I have 24 volts at the injection pump electrical terminals in the "start" position, but not "run" or "off". I DO have the TM-9-6115 manual, but am a bit unsure of how to proceed. Any help would be greatly appreciated.....

98G · Mar 14, 2018

I suspect the switch is wired wrong or faulty.

viking1 · Mar 15, 2018

98G said:
I suspect the switch is wired wrong or faulty.

Definitely wired correctly, worked perfectly before rebuild and hasn't been moved. I guess I could try and clean it first and the attendant relay. Wonder if those old switches are even available anywhere?

Guyfang · Mar 15, 2018

During "rebuild", was only the IP and injectors worked on? We're any other parts removed, or wiring removed? Because if someone works on something, and it runs before, and not after, whatever got "worked on" is suspect.

There should have been no reason to remove any wires, to pull the IP and injectors, but if so, I would start there. Could someone have miswired the dead crank switch?

viking1 · Mar 15, 2018

Guyfang said:
During "rebuild", was only the IP and injectors worked on? We're any other parts removed, or wiring removed? Because if someone works on something, and it runs before, and not after, whatever got "worked on" is suspect.

There should have been no reason to remove any wires, to pull the IP and injectors, but if so, I would start there. Could someone have miswired the dead crank switch?

Only IP and injectors were pulled to be rebuilt. There are of course the two wires that go into the ip for the solenoid, but nothing else was touched. I

Gunzy · Mar 15, 2018

There should be a wiring diagram on the inside of one of the panels. This will help you inspect the electrical being correct.

Guyfang · Mar 15, 2018

Guyfang said:
During "rebuild", was only the IP and injectors worked on? We're any other parts removed, or wiring removed? Because if someone works on something, and it runs before, and not after, whatever got "worked on" is suspect.

There should have been no reason to remove any wires, to pull the IP and injectors, but if so, I would start there. Could someone have miswired the dead crank switch?

The first thing I will do is correct myself. No dead crank on this set.

Hi Folks. I have an MEP004 with a white 4 cylinder diesel rewired single phase for backup power on my shop. I had someone else tear it down to rebuild the pump/injectors, as it was filling the crankcase with fuel and shutting down (although it runs great). Anyway the rebuilt parts are correctly back on, (who put them back on?) but now the issue is when I connect the batteries the engine immediately starts cranking (no matter what position the on/run/start switch is in). I disconnected the hot wire at the solenoid, (what solenoid?) but cant figure out that issue. Should I suspect a bad switch? (No, or I would not. I have seen maybe, two start switches in the 28 years of working on the 004A and 005A) It also wont start on diesel alone now (fires immediately on ether), (this could mean you are not getting 24 volts to the L1, engine fuel shut off solenoid) although it started and ran for about 1 minute initially. I couldn't get the engine to shut off with the switch, (S2, engine start, run and stop switch?) so I pulled the fuel line to shut it down (causing air to be allowed into the fuel line/IP) (shutoff (what means shutoff?) didn't seem to do anything either, but I guess that's normal?). The fuel pumps work normally with either the battle station switch or with the main switch in the "start" position (doesn't run on the other 2) (should also hear the fuel pumps run in the AUX position, with Battle Short switch on). I have 24 volts at the injection pump electrical terminals in the "start" position, but not "run"(no voltage in the run position, no fuel, wont start) or "off"(this is correct). I DO have the TM-9-6115 manual, (Do you have the -12 and the -34 TM's?) but am a bit unsure of how to proceed. Any help would be greatly appreciated.....

Now, if you re-hook the hot wire to the solenoid, (what solenoid? Start solenoid?) with the batteries unhooked, and place the CB1, (DC Control) in the pulled out position, can you hook up the battery cables? If so, the problem most likely is in he control panel.

Kenny0 · Mar 15, 2018

If you disconnect the start wire from the starter solenoid you should be able to have the batteries connected and be easier to trouble shoot with test light or voltmeter.

viking1 · Mar 16, 2018

Gunzy said:
There should be a wiring diagram on the inside of one of the panels. This will help you inspect the electrical being correct.

Yes Sir, I do see that. Verified all electrical is untouched and as it should be.

viking1 · Mar 16, 2018

Kenny0 said:
If you disconnect the start wire from the starter solenoid you should be able to have the batteries connected and be easier to trouble shoot with test light or voltmeter.

Yes Sir, did that. I'm thinking I may have 2 problems; 1)bad off/run/start switch or relay, and 2)air in the fuel lines. It ran really well for 1 minute and then stopped and wont restart again without ether. I'm thinking maybe it just ran the existing fuel out of the lines before I installed the rebuilt pump (injectors were rebuilt first)....

viking1 · Mar 16, 2018

Guyfang said:
The first thing I will do is correct myself. No dead crank on this set.

Hi Folks. I have an MEP004 with a white 4 cylinder diesel rewired single phase for backup power on my shop. I had someone else tear it down to rebuild the pump/injectors, as it was filling the crankcase with fuel and shutting down (although it runs great). Anyway the rebuilt parts are correctly back on, (who put them back on?) but now the issue is when I connect the batteries the engine immediately starts cranking (no matter what position the on/run/start switch is in). I disconnected the hot wire at the solenoid, (what solenoid?) but cant figure out that issue. Should I suspect a bad switch? (No, or I would not. I have seen maybe, two start switches in the 28 years of working on the 004A and 005A) It also wont start on diesel alone now (fires immediately on ether), (this could mean you are not getting 24 volts to the L1, engine fuel shut off solenoid) although it started and ran for about 1 minute initially. I couldn't get the engine to shut off with the switch, (S2, engine start, run and stop switch?) so I pulled the fuel line to shut it down (causing air to be allowed into the fuel line/IP) (shutoff (what means shutoff?) didn't seem to do anything either, but I guess that's normal?). The fuel pumps work normally with either the battle station switch or with the main switch in the "start" position (doesn't run on the other 2) (should also hear the fuel pumps run in the AUX position, with Battle Short switch on). I have 24 volts at the injection pump electrical terminals in the "start" position, but not "run"(no voltage in the run position, no fuel, wont start) or "off"(this is correct). I DO have the TM-9-6115 manual, (Do you have the -12 and the -34 TM's?) but am a bit unsure of how to proceed. Any help would be greatly appreciated.....

Now, if you re-hook the hot wire to the solenoid, (what solenoid? Start solenoid?) with the batteries unhooked, and place the CB1, (DC Control) in the pulled out position, can you hook up the battery cables? If so, the problem most likely is in he control panel.

OK Sir, I'm going to go thru your suggestions one by one. Greatly appreciate the info. BTW I was referencing the starter solenoid.

Guyfang · Mar 16, 2018

Like KennyO suggested, tape off the L4 (starter solinoid) wire and then you can start looking for the problem. Like I said, see if you can hook up the L4 wire after hooking up the batteries, with the CB pulled out. If the CB is pulled out, and it starts, then you may have a stuck relay.

viking1 · Mar 18, 2018

OK, have been battling this dreaded flu bug, but made some progress on the MEP today. After inspection I found a wire up above/behind the engine that had been chewed in half by a packrat. I quickly spliced it together, and the engine started & ran great. However I still have 3 problems;

1)There is fuel running out of this port on the side of the pump when the engine runs. What is this port, and why is it leaking? I might add my fuel strainer assembly was missing, so I just ran a normal line with a clear filter from the day tank to the pump (don't know if that makes a difference).

2)The throttle cable isn't yet hooked up to the pump lever, but moving the arm in either direction didn't seem to have any effect on engine speed. Am I missing something?

3)The starter still automatically comes on when I hit the solenoid (regardless of the switch). Which relay controls that starter circuit?

viking1 · Mar 18, 2018

I just saw in TM-5-6115-465-3 that hole appears to be where the high idle screw is supposed to go (and is missing)? Guess that would explain that. Will have to try and locate a replacement....

viking1 · Mar 18, 2018

OK guys, I feel very stupid (but I'm going to plead the flu). I just realized that hole in the pump in the picture above is for the engine stop lever (which I don't think does anything in this MEP004 application). I searched around and found it about 3' away from the generator on the ground. It had obviously been blown out by fuel pressure. Is there anything that holds this stop lever in place, and if so does that mean my pump rebuild was botched (even though the engine runs)?

Gunzy · Mar 19, 2018

viking1 said:
OK guys, I feel very stupid (but I'm going to plead the flu). I just realized that hole in the pump in the picture above is for the engine stop lever (which I don't think does anything in this MEP004 application). I searched around and found it about 3' away from the generator on the ground. It had obviously been blown out by fuel pressure. Is there anything that holds this stop lever in place, and if so does that mean my pump rebuild was botched (even though the engine runs)?

I would think it should have a jamb nut on it. Is it long enough to have one?

viking1 · Mar 19, 2018

Gunzy said:
I would think it should have a jamb nut on it. Is it long enough to have one?

No Sir, just a hollow shaft that pushes into the side of the pump housing. Cant see how it would stay in there under pressure unless its supposed to be secured from the inside.

Guyfang · Mar 19, 2018

viking1 said:
OK guys, I feel very stupid (but I'm going to plead the flu). I just realized that hole in the pump in the picture above is for the engine stop lever (which I don't think does anything in this MEP004 application), (But NEEDS to be there). I searched around and found it about 3' away from the generator on the ground. It had obviously been blown out by fuel pressure. (there is not enough pressure to do that. It may have fell out, but if fuel is only seeping from the hole, its not high pressure. The area that it goes through is not high pressure.) Is there anything that holds this stop lever in place, and if so does that mean my pump rebuild was botched, (OH YES) (even though the engine runs)?

.

Guyfang · Mar 19, 2018

viking1 said:
OK, have been battling this dreaded flu bug, but made some progress on the MEP today. After inspection I found a wire up above/behind the engine that had been chewed in half by a packrat. I quickly spliced it together, and the engine started & ran great. However I still have 3 problems;

1)There is fuel running out of this port on the side of the pump when the engine runs. What is this port, and why is it leaking? I might add my fuel strainer assembly was missing, so I just ran a normal line with a clear filter from the day tank to the pump (don't know if that makes a difference). No, this is not a port, nor for adjustment of the IP. There should be another linkage attachment sticking out of the IP. Its for the MEP-103 Precise Power, electric actuator. BUT IT MUST BE ON THE PUMP!. There is an O-ring on the shaft, to keep the fuel from leaking. This is not a high pressure area. If you continue to use this gen set without proper fuel filtration, you will be repairing/replacing the IP again. Along with the injectors. You say the fuel strainer is missing. Do you mean the primary and secondary fuel filters? Or the fuel strainer? Big difference. I could see using only one filter for the set, but no strainer? No. The strainer is there to take out the water. Another IP and injector killer. Take a look at TM5-6115-464-34, page, (PDF reader) 105 for an exploded view of the IP. Then you can have a better understanding of the IP
View attachment 722423

2)The throttle cable isn't yet hooked up to the pump lever, but moving the arm in either direction didn't seem to have any effect on engine speed. Am I missing something? Oh yes. The throttle linkage that you need to use, on the back side of the IP can not be operational, because the other side is missing.

3)The starter still automatically comes on when I hit, (do you literally mean strike the starter solenoid?) the solenoid (regardless of the switch). Which relay controls that starter circuit?

Here is the schematic. It is found on a plate on your gen set door, in the -12 and -34 TM's. K3 controls starter operation, but several other relays have to be energized for K3 to work. K3 could have its contacts welded shut.

View attachment Scan_0001.pdf

Guyfang · Mar 19, 2018

This is how your IP should look. Notice how the linkage plate on the side of the IP is wired to the front? That allows the linkage that is attached to the throttle cable, to control the IP. Thank GDG111 for the pictures.

Problem with MEP004

Member

Former SSG

Member

Moderator

Member

Well-known member

Moderator

Active member

Member

Member

Member

Moderator

Member

Member

Member

Well-known member

Member

Moderator

Moderator

Moderator