MEP 701A, MEP 831A or ???

I need some advise from some of you that have far more experience with these generators than I have, (Which is almost none).

I drive a 18 wheeler for a living. I need to mount a generator on my truck. I do not want a gasoline unit, I want diesel. Noise is an issue so it must be something with an ASK (Sound enclosure). I need about 3kw in size. PARTS AVAILABILITY is a big concern for me as I will be using this thing about 50-100 hours a week. Once I have one in place and working and it proves itself I plan to obtain a second unit and have it on hand for when the first one is completely worn out. Has anyone used one of these units to the point of complete uselessness, if so, how many hours did you get out of it?

I have seen several generators online that would fit the bill for about $1,500. These are all built overseas and are likely great for home use, but I do not believe they will hold up to being frame mounted on a semi. Not for very long anyway. That is why I am looking at the military units. I'm pretty certain they will hold up to the abuse much better.

I have tried to do some research on these 2 units and have seen and heard a 831 run in person. I like that unit from what I know about it. I really like the external fuel connection and the internal fuel pump on the 831. Does the 701 have that as well?

I know both units are 24vdc to start and take weird batteries. Can the starter be changed to a 12vdc? (As in, is there a 12vdc starter that will bolt up to the unit?) Maybe have the original starter rewound by a starter shop to be 12vdc? That way I can run a cable from the truck to the starter so the truck batteries (12vdc) can start the unit and truck will of course keep those batteries charged so the internal 24vdc charger will not be needed.

When I saw the 831 I investigated enough to see that it would be pretty easy to flip the control panel down, tap into the back of the controls and wire in a panel that can be remote mounted to both start/stop and monitor the unit. For that matter The panel could be removed, wires extended and the whole panel mounted remotely, (Which is very unlikely I will do that). Is there an easier way to remote start/stop the 831? Is the 701 as easy to remote start/stop?

Can somebody please tell me the primary differences between these 2 units? Would 1 be a better choice for my use than the other? Is there a different unit that you might recommend?

Thank you in advance for any and all help with this project!
 

Chainbreaker

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First off let me say I own neither one of these units. However, I was looking at purchasing a 701a for the past couple of years. From what I have heard, parts availability is becoming an issue with the 701a. Therefore, I have directed my focus to looking at the 831a for better parts availability and a lot more reasons.

The 831a uses a Yanmar (Japan) diesel which is pretty quiet plus everyone that has one seems to REALLY like it...those that own one will chime in soon I'm am sure! If I recall correctly, the 831a can throttle down in low demand situations thereby using less fuel. There are quite a few 831a's that are being surplused so availability is MUCH greater than the 701a. Both units have the aux fuel hook up feature. If you are going to be running the unit 50-100 hours a week I would not worry about battery charging as that will be more than enough time to keep the onboard battery fully charged. So I would stick with the OEM battery if possible and not mess with any conversion of starter or running additional battery wires. The simpler you can keep it the more reliable it will be.

Since the 831 uses more modern electronics I would think there would be a multitude of ways to remote start the unit and perhaps monitor it using something like a Rasberry Pi or Arduino kit approach. There could be someone out there doing something like that and might be able to offer a kit solution.
 

Chainbreaker

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Here is a good thread (12 pages worth) on the 831a if you have not already read it. Would give you some idea of what to look for as far as any problems with a used unit. Also, there is some discussion about batteries and in particular one about using 2 motorcycle batteries instead of the expensive commercially available 24V battery.

http://www.steelsoldiers.com/showthread.php?132681-MEP-831-FAQ-for-owners-or-potential-buyers

Edit: If you look at pg 7 post #64 there is mention of a remote start harness. 2nd photograph. Comments were that it might have been a military installed option. Of course you would also need whatever they used to hook to that harness. Never the less, remote starting is definitely achievable.
 
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Chainbreaker,

Thanks for that. I did start reading the first few pages of that post and intend to get back to finish it when I have a little time to do so.

This may be premature (pending on what that thread says about the remote start) but does anybody have info on this? Is/was it a kit? Are the parts still available?
 

FloridaAKM

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I have a 701a & it is LOUD despite the ASK, not to mention heavy & large. The battery will run you about $285.00 dealer cost from NAPA (it is an ITAR also)& the charging circuit is prone to failure. Your much better off with the 831a as it is readily available for surplus purchase & parts are not scarce.
 

36racin

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Appears the 831 is going to be the better choice for you if it fits your power requirements. Here's a good place for gen parts https://greenmountaingenerators.com/ I believe I saw somewhere that sells a remote start panel for these. Ill see if I can find the site. Just keep in mind the mounting of this unit will require you to be able to access it for regular maintenance. Like oil changes every 100 or so hours. If being used on the road will some sort of shock/spring type mount going to be used? Or a solid mount? It may make a difference? Some of the other experts can chime in on the mount. The prices on the 831's are rising for newer, low hour machines. I've seen recent prices up over 1K on some units. In Florida Eglin AFB has had a few units, next closest to you is probably sales in Georgia or North Carolina. Or you could always buy off Evilbay or Craigslist sites.

I own a Yamaha ISEB 3000 generator for use with my camper. It's a Inverter Technology generator also. Owned it for 10 years. Not one issue with it. Gasoline powered, great fuel efficiency, light weight compared to others its size and quiet. I also have a 701a with enclosure. It's still loud, very heavy and no variable speed control.

Get the 831. I'm looking for one and will get rid of my 701 when I do.

Todd
 
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Appears the 831 is going to be the better choice for you if it fits your power requirements. Here's a good place for gen parts https://greenmountaingenerators.com/ I believe I saw somewhere that sells a remote start panel for these. Ill see if I can find the site. Just keep in mind the mounting of this unit will require you to be able to access it for regular maintenance. Like oil changes every 100 or so hours. If being used on the road will some sort of shock/spring type mount going to be used? Or a solid mount? It may make a difference? Some of the other experts can chime in on the mount. The prices on the 831's are rising for newer, low hour machines. I've seen recent prices up over 1K on some units. In Florida Eglin AFB has had a few units, next closest to you is probably sales in Georgia or North Carolina. Or you could always buy off Evilbay or Craigslist sites.

I own a Yamaha ISEB 3000 generator for use with my camper. It's a Inverter Technology generator also. Owned it for 10 years. Not one issue with it. Gasoline powered, great fuel efficiency, light weight compared to others its size and quiet. I also have a 701a with enclosure. It's still loud, very heavy and no variable speed control.

Get the 831. I'm looking for one and will get rid of my 701 when I do.

Todd
If you can find the source for the remote start that would be awesome!

Mounting will most likely be solid mount to the frame unless experienced users here strongly recommend some sort of shock isolation which is doable but will increase complexity of the mounting and of course cost so if it is not really necessary I don't want to do it.

The 701 is definitely out.
 

Chief_919

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Honestly, for this application I would probably look at used Onan or Power Tec diesel generators made for RV's. Shop around a bit on the used market and you can find them around what you would have in a running, known good 831A especially down there in Florida. And they are already set up for remote start so no expense and time in making that happen.

A friend of mine ended up setting his truck up with a battery bank and inverter. The batteries charge off the trucks electrical system through an isolator and he usually doesn't need to charge them at stops, but he got a small generator off a highway sign board that is essentially a little diesel engine coupled to a GM alternator that he fires up when needed on longer stops.
 

DieselAddict

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Doing a remote start is pretty straight forward. Are you able to do your own? It will take a few switches and wiring. Totally doable if you have some basic wiring skills.

Edit - Since these machines are not in production anymore and some parts are specific to the 831 you have to be prepared for parts that are hard to find and/or expensive. Engine parts are plentiful. Most of the electric parts (relays and such) are pretty standard. The governor and alternator are unobtanium (expensive if you do find them). The inverter can be found on Ebay here and there.

Something to keep in mind. If you are going to be relying on this day in and day out I would recommend going with something that is in production with a spare parts available.
 
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Triple Jim

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Agreeing with Chief_919, RV generators are designed for high duty cycle use, and the new versions are extremely quiet. The last one I heard running was so quiet I could sleep next to it in a sleeping bag with no trouble.
 
Doing a remote start is pretty straight forward. Are you able to do your own? It will take a few switches and wiring. Totally doable if you have some basic wiring skills.
That's pretty much what I was thinking. I'm pretty good at installing wiring and making it look factory with all the proper crimp terminals, routing, chafe protection and so forth.

Does not look that hard to just tap into the needed controls at the back of the main panel there and run the wires into the sleeper and make a panel to hold the necessary/wanted stuff there. Unless I'm wrong all I need is the preheat and start/run switches?? Adding a good voltage meter (and maybe a frequency (Hertz) meter) would not be a bad idea. I think I would put a quick disconnect plug (Weatherproof) so that removing the gen if needed would be pretty painless.

The main reason I would like an "official" remote kit is to keep it as stock/factory/military as possible but on the other hand, what difference does that really make? As long as what I do does not adversely impact proper and safe operation or durability, who really cares if it is "Milspec" or not?

I think one thing I would like to do and I'm surprised they don't come that way, is to make a cover or door that will at least somewhat protect the main panel from the elements and in my case, idiots walking by from tampering with things.
 

m715

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may I ask how much you think it will cost to buy a generator then find or make the remote start? How and where are you mounting this on your truck?
 

DieselAddict

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On these units there were a few different remote start setups depending on how it was being used. They were field installed. I've not seen a kit that has a remote panel. They were mostly used with a control system for doing hybrid solar power systems. Solar Stik used the 831 on their solar hybrid setup. I checked and they have removed all that stuff from their website. Plan for a DIY setup.
 
Main problem with RV units, especially Diesel ones is the cost.

Even used, a fairly recent model in decent contrition is pretty expensive. I have seen some very old ones (parts availability?) for over $1,000.

The more current models are running $3-5k I'm actually watching one (2011 Cummins Onan 3200 Diesel RV Generator) now over on that big "E" site to see how high it gets. Right now it is at $2995 and I don't think that even includes the inside control panel. I sent the seller a question about that and the hours (since he did not bother to list the hours). I have not heard back yet. But either way, I don't really want to spend that much and I'm certainly not getting a new one, they sell in the +$6K range.

AND... the oil change interval is no better than the 831 at 100 hours.
 

DieselAddict

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To get a MEP831 that has been checked out and in good shape should cost you around $2.5k. I have a one that is new and I know I would not take less than about $4k for it.

You can always find one "cheap" but understand that these are different beasts than most generators. Know what you are getting and know the risks.
 
may I ask how much you think it will cost to buy a generator then find or make the remote start? How and where are you mounting this on your truck?
They are selling on that "E" site for $1,200 to about $3k. I may look into that government surplus site to see about getting one but I know those can be somewhat of a crap-shoot getting a decent one or a huge paperweight.

A DIY remote set up I can fully fabricate in a professional looking way for $100-150 depending on if I decide to put voltage and hertz meters or not and how much I end up spending on them. If I just go with the 2 needed switches and some wire, loom, ty-wraps and a weather proof QD plug probably in the $50-75 range for the remote.

Mounting will be either on the top of the frame behind the sleeper or along the right side frame rail, more or less in the traditional location for an APU. I prefer the top of the frame location but I may have interference issues with the trailer. I am going to build a lightweight 1x1 tubing frame 2" larger than the generator and bolt it into place for a couple weeks and see if it gets hit by the trailer or not to determine if I can safely put the generator there. IF it gets hit it will bend up easily and not damage the trailer. I'm not worried about turning, it is more the bend angles encountered when the truck is on level and the trailer is on an incline and turning at the same time, (Like a steep driveway leading to a level street) with the long wheelbase of a 53' trailer there is a lot of stuff happening in that space, especially because I have an extended front on the trailer. Having an extended wheelbase on the truck as well only makes things worse in that driveway condition.

May I ask why you ask?
 
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Chainbreaker

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Mounting will most likely be solid mount to the frame unless experienced users here strongly recommend some sort of shock isolation which is doable but will increase complexity of the mounting and of course cost so if it is not really necessary I don't want to do it.
Your truck already has suspension that will help dampen road vibration but I would consider installing some 3/4" horse stall mat material (found at feed stores) under the skid and bolt through it. I installed 2 strips of that under one of my generator's skids and it worked out very well. Probably all you need to give it a little extra dampening from running the genset when stopped (quiet hours) and a little extra road vibration isolation.

I'm sure an 831a could work, however I would not rule out the RV generator suggestion. With the 831a being a mil spec unit some parts are going to be difficult to find if you encounter a problem while on the road. With an RV genset you can probably pull into any RV maintenance shop on the road and find parts or they will know where to find them quickly. If you can get a good deal on a load tested reliable 831a then go for it. But...if the price creeps up with a higher cost than usual purchase price plus added cost to add remote start/monitoring features then you may push the price into the range of a good used RV unit. Even at a slightly higher cost an RV unit might be better for your situation in the long run. If you look on Craigslist you can usually find quite a few used RV gensets pulled from RV's.
 

Chief_919

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Main problem with RV units, especially Diesel ones is the cost.

Even used, a fairly recent model in decent contrition is pretty expensive. I have seen some very old ones (parts availability?) for over $1,000.

The more current models are running $3-5k I'm actually watching one (2011 Cummins Onan 3200 Diesel RV Generator) now over on that big "E" site to see how high it gets. Right now it is at $2995 and I don't think that even includes the inside control panel. I sent the seller a question about that and the hours (since he did not bother to list the hours). I have not heard back yet. But either way, I don't really want to spend that much and I'm certainly not getting a new one, they sell in the +$6K range.

AND... the oil change interval is no better than the 831 at 100 hours.
You are going to run about the same price for an RV unit as a good running 831A.

But in the long run when it comes to maintaining it the 831A will be more expensive and frustrating. That RV Onan set you can find parts all over on the road, any Onan dealer will have it or get it next day. MEP-831A parts not so much- look right now and see how easy you find a starter for example. we have folks on this site right now looking for the fault panels without luck. even minor things like relays, the 12v are easy to find and 24v not so much.

Using one as heavy as you plan to the logistics of supporting it changes the equation long run.
 
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