New guy from NW Florida MEP002a questions

[Hdonly]

Hello all. New from NW Florida with an MEP002A I bought for $300 off Craigslist. The control box and connection box is missing from it. All the cannon plug connectors are still on it. Engine turns over freely . My first question is: If I make sure all loose wires from the gen head are taped up so no shorts, can I run the engine without doing any damage to the generator head? I would like to check out the engine before putting any real money into it.
Thanks

 

[DieselAddict]

Yes and no. If you secure all the generator leads you won't do any damage there. The issue you may run into or has already been run into is the injection pump can get tight which will cause some damage if you spin the engine over without first making sure the injection pump is free.

First thing to do is inspect the injection pump to see if it is free and if its not you'll need to get that in good shape before doing much with the engine. Once the injection pump is off take some time and clean all the fuel lines out. Looks like its been sitting for a while with the "patina" on the unit.

Pay close attention to the fuel tank. Its not uncommon to have water in there.

Do a search here on the forum for " Ambac" and you'll find plenty to read about the injection pumps.

 

[Hdonly]

Thank you. I planned on pulling all the filters and flushing the tank (it has about a 1/4 tank) The engine oil looks really good, but I think I will change it first anyway. I rotated the engine with a large screwdriver through the screen cover. It rotated fairly easily. It has no muffler on it. I will check out the injection pump before putting any power to the starter.

 

[Chainbreaker]

I would say a bit rough, but... if it's a solid engine you have a good start and a low investment... so far.

I would definitely not put 24 VDC battery power to anything yet. Lots to verify. As DieselAddict said, the injection pump is known to break the key inside if gummed up. Use the SS search function there is a LOT written about how to free it up without damaging it. Also, the fuel pump bottoms need to be taken off & the basket screen in each pump need to be removed and cleaned at the very least. Also, make sure it has an air cleaner inside the air intake cannister.

Once you are certain the injection pump is free, I would take off the valve cover & do a visual on the top end. Not knowing the history, I would drain the oil & search though it with a magnet & visually looking for ANY TYPE of metal etc.

Also, have you downloaded the manuals (TM's are at the top of this page). They are key to understanding & maintaining this machine assuming you have never owned one before.

Also, I can't believe it still has the 55 gal aux fuel hose adapter sitting in its holder! Saw one on one of the auction sites for $130 without the brass fuel drum rods!

 

[Hdonly]

When I rotated the engine, I only moved it a little bit. I just wanted to know it wasn't stuck. The exhaust pipe/muffler is gone but someone did stuff rags in the exhaust ports. I did download all the manuals. I was going to pull all the filters and pump screens yesterday, but it rained all day here. I did cover it up so no more pouring rain on it. I did notice the fuel adapter and wondered what it was. I was really surprised what people are asking for those things. Maybe I could use it for "horse trading" material for some other pieces and parts.I figured it out after joining the forum here. Spent yesterday reading about the injector pump and studying about the electrical side of this set since the control and connection boxes are missing. I have been studying the wiring schematics and thinking about the SX460 regulator set-up. I am no engineer, but I have a lot of electrical experience from my previous life working on water well and sewer pump control equipment. Hope I can bring this unit back to life. I do live in harrycane country and generators are a good thing here. Thank all so much.

 

[Chainbreaker]

BTW, there were some MEP-002a/-003a mufflers (-003a is same, just 2X) listed on eBay a while back but haven't noticed any recently.

You can look up the NSN P/N in the -24P manual and do a broad search using the NSN #. Never know what might pop up. Also, you can check the classified ads here on SS or put in a "parts wanted" ad as well.

 

[Light in the Dark]

There are a couple up: https://www.ebay.com/itm/294004090506

 

[Hdonly]

There are a couple up: https://www.ebay.com/itm/294004090506

Just checked. Message says seller on vacation. Check back later. Thanks for the heads=up.

 

[Light in the Dark]

I think this is a bad description... you might want to reach out to these folks: https://www.easternsurplus.net/PartDetails/10032/10-KW-Exhaust-Muffer-Generator-400HZ-MEP-813A

Looks like the same Onan muffler for the 00X series, not an 813A.

 

[Hdonly]

Starting to think I may just cut some flanges out 1/4" and weld some steel tubing and build a manifold and find a universal small muffle. I have most of that stuff in my junk pile.

 

[Ray Cook]

First off, welcome aboard!

Next, you may have read about this already, but there's 2 different (but interchangeable) injection pumps on these engines. the earlier ones use a model PSU from Bosch. Later ones have the M50 from Ambec. Hopefully, if you have a PSU it didn't bind up as the pump shaft breaks when that happens, and the pump becomes a green paperweight. The M50 pumps are repairable.

Determining which pump you have is pretty easy. With the pump on the engine, touch the bottom of the pump body. If you feel a screw head, that's a PSU. If it's just a bump sticking down from the pump body, that's an M50. Keep us posted

 

[Chainbreaker]

Starting to think I may just cut some flanges out 1/4" and weld some steel tubing and build a manifold and find a universal small muffle. I have most of that stuff in my junk pile.

You might as well if you have the time & tools vs shelling out $150 - $200 on a muffler for an engine that is in unknown condition. That's money better spent on other required parts down the road. Regardless of what you put on it... it's still going to be a fairly loud air-cooled diesel.

BTW, there was another member "RustyStud" who USED TO post here who did a conversion on a MEP-002a using the SX460 AVR. He posted a couple pic's & sketch of how he wired it. Search using something like "SX460 AVR" & member "RustyStud" & it might come up if your lucky.

Edit: I did a search for you & here is what I found, there may be more: Search results for query: SX460 AVR | SteelSoldiers

 

[Guyfang]

Rusty is still alive and kickin.

@rustystud

 

[Hdonly]

Yes, reading Rustystud's posts is what got me thinking about going the SX460 AVR route. Since all of my control box and connection box stuff was missing when I got it, the SX460 will be the most economical way to making electricity- of course after I prove the engine will run. Thank you all for keeping me pointed in the right direction. Didn't know anything about this genset till I came to this forum.

 

[Chainbreaker]

Rusty is still alive and kickin.

@rustystud

Yeah, but I don't think he comes around here (Generator Forums) anymore. He must've gone solar!

I too would like to eventually go the SX460 route as well (4x units) to eliminate future problems inherent in the fault prone AC Output Control Box. Thereby eliminating the inherent unreliability's of the overly complex sticky switch mechanism, current transformers, reactor, etc. lurking in that "mouse house den" box. I really don't need nor want the 3-phase option. However, it seems from reading past posts there were some implementation issues that never quite got ironed out completely & are beyond my generator electronics knowledge.

Sure wish someone like @kloppk would iron out the details and offer a verified fully tested SX460 install/implementation kits & instructions for MEP-002a/-003a. There's definitely a market for it! The Onan Air-Cooled Diesel based mil spec generators never really seem to die, they last for "generations"!

 

[Hdonly]

Well crap. After I got home from my heart doctor appointment, I checked out my injector pump. Dang the bad luck, I have the Bosch pump. I think the procedure to check if it is free is the same for both pumps?

 

[Ray Cook]

I believe it is. The pumps are very similar, with the exception of how the pump shaft is rotated.

I forgot to mention in my earlier post that there's also an ID tag on the outside of the pump body that tells you which pump model you have. However, it is difficult to see with the pump on the engine. If I remember right, the tag will be on the side of the pump base that faces forward (towards the fan). Hopefully your pump is OK.

 

[Ray70]

At this point you might want to consider just pulling the pump off and taking it apart to be sure it's good.
The problem with the PSU pump is that it's " shear pin" design is somewhat flawed such that the plunger itself will often snap in half at it's thinnest point rather than the head breaking off the drive pin as designed. If the plunger snaps you are all done and need to replace the entire pump.
Seeing that good pumps are almost impossible to find these days I would not take the risk of potentially snapping the plunger.

Also, once you get deeper into this machine, if you want a stock muffler I can hook you up for a super fair price.

 

[Chainbreaker]

... Seeing that good pumps are almost impossible to find these days I would not take the risk of potentially snapping the plunger.

Yep, better handle that pump with white gloves on!

FYI - There is currently one of the "Ambac Fuel Pump 50-2/4A-80A-9540A" on eBay where the eBay scalper wants $2,150 + $90 shipping for a USED ONE. I saw a new one for ~$1700 recently and thought that was high. Those prices are in the range of a semi-complete parts MEP-002a/-003a parts unit. I remember a few years back pumps were in the $250 (working used) - $750 (new) price range.

 

[Ray70]

Heck, for that kind of money I have a good Ambac M50 pump for sale that comes with a spare low ( 250) hour, fully tested and serviced 002A attached to it !
Not too long ago I was able to buy M50 rebuildable cores for $50-75. Now it's cheaper to buy a whole machine just to rob the pump off it.