New to me - MEP-003A

[Mr4btTahoe]

Hey alls..

Been lurking around the forum for a few weeks now as I've been trying to work out a deal on a MEP-003a that I've had my eyes on. The unit was forsale on FB marketplace for some time.

After a month of back and forth with owner, we finally made a deal and we drove down ~2.5hrs to pick it up.

Once we got there, he told us how he was in the unit that this generator was originally deployed to and when his unit disbanded, he ended up with this unit. He gave me the original tech books and training manuals that he was given along with the auxiliary fuel hoses, etc. He said the last time he had it running was 2003 which it powered his home construction site for 2 months off/on until they had power ran. Since then, it has been stored indoors. They were able to get it to crank over and could get fuel to the injection pump.. but nothing out of it when they tried to get it running before we bought it.

After doing some digging on here, I'm pretty certain its a frozen pump plunger.

Anyways... here it is as we picked it up after handing over $600






The books it came with... (also came with 2 original oil filter kits issued in '91)







First things first... I pulled the fuel tank and washed it out. MIGHT have something to do with why it wouldn't fire...




Orange on top... white/chunky on bottom. Some of the nastiest fuel I've ever smelled. Got the tank washed out and its in the shop drying out for the night.

Also have a pair of batteries charging up for it. Plan is to pump a qt or so of ATF through the fuel system with the priming pump and let it sit for a few hours.. then pop the pump apart and see if that plunger is frozen. If so, get it moving along with the throttle linkage.


After that, I'll put a few gallons of fresh diesel in the tank and purge the whole system again with fresh fuel and see if I can get it to come to life. If I get it running, I'll test the electrical side and then fully service the unit. New fuel filters/seals, oil filter and air filter. Oil in the unit currently looks clean so I'd say it will be ok for the initial testing and such. I'll also change out any hoses that look questionable such as fuel or oil cooler lines. A new set of glow plugs will also be in the works.


Then I want to go over the electrical with a fine tooth comb. Replace or clean anything that looks suspect. Then possibly a partial tear down... cleaning.. and re-paint.


Once its back in top shape... if I can get it there... it'll go on a concrete pad a hundred+ feet from the house and will probably end up with a small shed built around it to keep it out of the weather and help direct the noise. It'll be used as back-up emergency power for our home.


Anyways.. more pictures and video will come when I get back out to it. Hoping to hear it run tomorrow.


I'm sure I'll have lots of questions

 

[glcaines]

The MEP003A is a very good genset. Very dependable. You need to thoroughly clean out the fuel system and change the oil and filter before doing anything else. I have listed some part numbers to get you started.

Oil Filter:
FRAM CH6PL
NAPA 1004

Fuel Filter:
FRAM 1125PL
NAPA 3113

Air Filter:
NAPA 2222

I removed my fuel tank and placed a lot of dawn dish detergent in it with water and a couple pounds of small gravel and shook the tank for a considerable time. I then rinsed it out, making sure I removed all of the gravel. I then filled the tank full with white vinegar and let it sit for three days. I removed the vinegar and repeated the gravel and soapy water treatment. After rinsing thoroughly with clean water, I rinsed the tank several times with isopropyl alcohol to make sure I removed all of the water. I then dried it out with a hair dryer. You need to remove and clean the screens on the bottom of all three pumps. This is an easy task. Next is fuel filters. As you mentioned above, flush the system out thoroughly with clean diesel. I added diesel clean to the fuel tank after completing all of this. Make sure you heat up the glow plugs before attempting a start. Once started, continue holding the starter switch in the start position until the oil pressure comes up.

I didn't change the oil and filter until I got the unit running. I let it run for ~15 minutes until the oil was hot and then drained the oil and changed the filter. I use Rotella 15W-40 weight diesel oil in mine. Read the TMs. Make certain you use proper grounding for your application. Grounding rod for remote use. Don't use a grounding rod when connecting to your house for backup. Connect generator ground to the house ground. Be careful, these generators can kill you if proper procedures are not utilized.

Never let the unit idle, as this will likely destroy your voltage regulator. The generator should be run at 60 hz and when you shut it down, it should be running at 60 hz. This is very important.

 

[Ray70]

When you dig into the pump there's a good chance you will find that the "dogbone" ( I forget the real name ) is split open and will need to be replaced.
If so, it's relatively easy and the part is available directly from Ambac. If you need the schematics or timing instructions, they are available here in the TM section or PM me and I can send them to you.
Good luck, you'll find all the info you need here

 

[Mr4btTahoe]

I'm hoping to not have to dig too deep into the pump to get it going considering it ran good before sitting and doesn't have many hours on it.

Hopefully I can get away with a good cleaning. We'll see though.

Thanks for the input guys... we'll see what happens tomorrow hopefully.

 

[Guyfang]

Glcaines has outlined the right way to do this. And I personally would not use ATF. Some of the guys use Seafoam. It appears to be a very good product. The student hand book is good reading. And I wish you would scan it and post it in the SS TM forum. But the rest of your books are so very out of date, that I would not use them. Look in the SS TM forum for the most current TM's. There are some big mistakes in the schematics in your books.

 

[doghead]

Your electric fuel pumps will need cleaning too.

The bottom twists off and there is a screen in there to clean.

You should be able to hear the pumps, until they make pressure. If they make no sound at all, they may be stuck with junk. If so, they may need replacing.

 

[redlight]

I had a 5 KW unit as well with the same symptoms. It could get fuel to the injector pumps but it did not show at the injectors. I also thought after reading the TM's and reading all about the unit, that the piston was stuck. A wise man (GUYFANG) said to make sure that the fuel cutoff solenoid was opening. It is located after the injector pump towards the front of the engine. I never would have looked there as the unit is physically in front of the pump and and it does not look like it is part of the fuel circuit. When it receives power, it raises a valve and fuel should flow. You can manually, with a screwdriver, raise the lever while another person turns the start switch. It needs 24 volts and a good ground to operate. I attached a jumper wire from the ground terminal as well as having the wire harness ground. then the solenoid operated properly and the unit ran fine and produced power. After many trial runs, I removed the jumper wire and the unit continued to operate properly. Who knew why it fixed itself. SO make sure the fuel cutoff works before pulling you hair out.

 

[glcaines]

I had a 5 KW unit as well with the same symptoms. It could get fuel to the injector pumps but it did not show at the injectors. I also thought after reading the TM's and reading all about the unit, that the piston was stuck. A wise man (GUYFANG) said to make sure that the fuel cutoff solenoid was opening. It is located after the injector pump towards the front of the engine. I never would have looked there as the unit is physically in front of the pump and and it does not look like it is part of the fuel circuit. When it receives power, it raises a valve and fuel should flow. You can manually, with a screwdriver, raise the lever while another person turns the start switch. It needs 24 volts and a good ground to operate. I attached a jumper wire from the ground terminal as well as having the wire harness ground. then the solenoid operated properly and the unit ran fine and produced power. After many trial runs, I removed the jumper wire and the unit continued to operate properly. Who knew why it fixed itself. SO make sure the fuel cutoff works before pulling you hair out.

This is a very good comment. If my MEP003A doesn't immediately start firing, I stop and manually lift the fuel cutoff solenoid with my fingers and then release it. The engine almost always immediately starts.

 

[Mr4btTahoe]

Did a good amount of work on it this afternoon while the weather was nice.

I cleaned out the fuel tank last night and let it dry overnight. I mounted it back on the unit and added 4 gallons of fresh diesel and a qt of ATF. Pulled the bottom filters from the pumps. All the filters were clean but the pumps had a little sediment in the bottom that I cleaned out.

(Reason for using ATF is because I've had great luck with it in the past unsticking timing advances and plungers on old stanadyne pumps. Fill the fuel filter.. crank it over until the IP fills up... let it sit overnight. 90% of the time, it will free up any stuck components without pulling the pump apart and chancing damage. It will also help lube the pump/injectors and will burn without issue hot/cold when used in low quantities.)

Anyways.. unhooked the supply to the IP and flipped the master switch to prime/run. Nothing but a click. After some quick reading, ran a ground wire from the batteries to the pump mount and the pumps grumbled a bit but then started whirring along. I ran the hose into a jug and grabbed another jug. First I cracked the valve on the fuel strainer and let it run until clean (1/2 gallon or so)... then did the same with the primary and secondary fuel filters. Sealed the valves back up and let the pump continue to cycle for a minute or so until the fuel at the injection pump feed hose was clean.

Shut off the pumps and hooked the fuel lines back up.

Dumped the ~1.5 gallons of skunk diesel into my waste oil centrifuge barrel then unhooked the main return line to the fuel tank. Kicked the pumps back on and let fresh fuel flow through the IP until clean. Dumped that mess into my barrel and then continued cycling the pumps until the diesel fuel was clean with a slight tinge of red.

I hooked the return hose back to the tank and just let the pump cycle for 5 minutes or so.

Checked the fuel lines for leaks and then decided to see if it would kick off. Hit the preheat for a bit then cranked it over. I let it crank for ~10 seconds while watching the oil pressure gauge. Oil pressure came up but didn't get any smoke out of the pipes and I don't think the IP fuel solenoid did anything.

By this point, it wasn't cranking all that fast and I knew the main battery cables and such were an issue along with some ground straps needing attention... so I decided to pull the batteries and put them on the charger for the night. I'm going to clean the throttle controls/cable and lube everything later tonight. I'm also going to see if the plunger on the solenoid is stuck.

Tomorrow afternoon, I plan to put the fresh batteries back on the unit and see what I can get it to do. If it still doesn't produce any smoke and the fuel solenoid is working, I'll crack an injector feed and see if I'm getting anything. If not... I'll go from there.

Thanks for the input guys.

 

[Mr4btTahoe]

Tinkered around a bit more after finishing up a customer's car tonight. Spent ~20 minutes getting the throttle linkage at the IP to move freely. Lots of cleaning... lots o' lube. Linkage moves nicely now through it's full range. It was frozen before.

The solenoid moves freely. Didn't apply power to it to see if it moved or not.

The throttle/frequency control cable on the other hand is frozen. The linkage end is fine... but the handle end is frozen up pretty good. I messed with it for ~30 minutes or so and couldn't get it to budge. It will turn slightly.. but that's it.

I may submerge that end in wd-40 for a day or 2... will probably have to replace it though.

 

[F18hornetM]

Never let the unit idle, as this will likely destroy your voltage regulator. The generator should be run at 60 hz and when you shut it down, it should be running at 60 hz. This is very important.

This is interesting, Although I don't really let anything idle for extended periods of time, hot diesels will cool down at idle. I even looked in TM and best I can see, it says nothing about slowing the unit down before shutting off. It just says shut breaker off and turn switch off.

Not to hi jack post, but I thought this may be important to others as I have always let idle a few minutes before shutting down. Looks like I may have been doing it wrong according to your post.

 

[Light in the Dark]

Yeah the throttle control cable should frankly only ever be used to adjust hertz, not RPM. Keep it at 1800, keep it happy, keep it running.

 

[Dock Rocker]

This is interesting, Although I don't really let anything idle for extended periods of time, hot diesels will cool down at idle. I even looked in TM and best I can see, it says nothing about slowing the unit down before shutting off. It just says shut breaker off and turn switch off.

Not to hi jack post, but I thought this may be important to others as I have always let idle a few minutes before shutting down. Looks like I may have been doing it wrong according to your post.

Really the idle down is for turbo diesels to allow the oil to circulate through the turbo to cool it off and not cook the oil that’s in the turbo housing.

It’s hard for me to not warm up or cool down a diesel because it’s been ingrained in me, but there is just to much info that says it will damage a genset.

I crank my generators off at the same throttle setting as i turned it off at. It kills my soul a tad every time I do it though.


Sent from my iPhone using Tapatalk

 

[F18hornetM]

I agree with you its ingrained in us mechanics. Although a turbo does have tremendous heat in it. I've worked on a mess of other commercial generators [and diesel trucks/equip]and like you said they start at load rated RPM which kills me, however they have block heaters that stayed plugged in year around. So oil is nice and warm, not 25 degrees. The ones that are trailer mounted and not plugged in really pluck my nerves.. LOL
I will continue to start at idle on this machine but I will shut down as you guys say for the sake of the regulator. Not for the engine.

I always learn something new here, thanks for mentioning that

I do have a question about shutting down at 60hz, if its not under any load, why would shutting it down at idle hurt the regulator??

To the original poster, those 3 fuel pumps can be cleaned by taking apart and new fuel tanks are available. Although after replacing mine a few years ago still wants to rust the cap and the very top. I keep it very full to prevent this. When I get time may make a new one out of stainless

 

[Mr4btTahoe]

Fuel pumps are working now... was a ground issue.

Now I'm trying to sort out an issue with the fuel cut solenoid. It isn't getting power to either post on top when the master switch is in the run position.

I still need to make new main cables and I believe I'm going to run a ground strap from the batteries to the frame for good measure. I'm searching through manuals at the moment... any quick tips on where power comes from for that solenoid?

On another note... I did get a little bit of smoke out of the exhaust that smelled of skunk diesel... which is kinda odd since the fuel solenoid isn't working....


Thanks

 

[Guyfang]

1. When you remover the electric fuel pumps, did you notice if all the mounting bolts had serrated washers? They are supposed to, to give you a better ground. So if there are none, you might consider getting them.

2. You only get voltage to one side of the fuel cut off solinoid. The other is for ground.

3. Can you read a schematic? If so, then follow the path that SHOULD power up the fuel cut off solinoid. If not, say something. Then some lazy person like me or one of the other guys, will tell you what and where to check.

4. HINT: it all starts at the S1. You should read the -12 manual, the first 20-30 pages. It explains HOW the gen set functions. Every gen set the army ever had, functions the same way. Durring the start funtion, all engine safety's are bypassed. After the S1 is released, the engine safety's are then in operation. Durring start, and after S1 release, the fuel cut off solinoid has to be energized for the engine to start. So, this should get you started.

 

[Mr4btTahoe]

I can somewhat read a wiring schematic... takes me a bit but I can do it. Just working on finding it at the moment.

I knew that only one side of that solenoid would be hot.. just didn't know which side so checked both. Nothing on either in the run position.

I'll dive into the diagrams/schematics tonight and see what I can sort out. I also plan to build new cables for it tonight.

EDIT

Looks like I wont see power at the solenoid unless the oil pressure switch is closed or the S1 is in the start position. I suppose I could jump the oil pressure switch and that would allow me to test for voltage at the solenoid in the run position. Kinda hard to crank it over and test for voltage at the same time.

 

[Guyfang]

I can somewhat read a wiring schematic... takes me a bit but I can do it. Just working on finding it at the moment.

I knew that only one side of that solenoid would be hot.. just didn't know which side so checked both. Nothing on either in the run position.

I'll dive into the diagrams/schematics tonight and see what I can sort out. I also plan to build new cables for it tonight.

EDIT

Looks like I wont see power at the solenoid unless the oil pressure switch is closed or the S1 is in the start position. I suppose I could jump the oil pressure switch and that would allow me to test for voltage at the solenoid in the run position. Kinda hard to crank it over and test for voltage at the same time.

Not just the oil pressure switch. ALL engine safety's. That's the reason S1 provides the "jumper" for you. In the start position, S1 circumvents all the safety's. So if you have not voltage at the solinoid, the circuit between the start switch and the solinoid is where you start.


Two ways to do the voltage checks when your arms are too short. Get help. Or get some roach clips, (alligator clips). And I also had a few cables made up to extend the multimeter cables. And a few cables with roach clips on both sides. But unless you intend to do this as a living, or have been bit by the generator bug, you don't need all this stuff.

Your close. Look again.

 

[Light in the Dark]

Back when I had my 002, I had a couple wires with alligator clips fabbed up for just that. https://www.lowes.com/pd/Gardner-Bender-2-Pack-Plastic-Standard-Wire-Connectors/4582329

 

[Guyfang]

They can be a life saver, when you just don't have time to fix it, or the part just ain't here yet.