Valence's 1990 Turtle Mountain M116A2 Power Plant AN/MJQ-33

[Valence]

Yes, yes I have purchased another trailer (purchased on September 5th, 2019).

This trailer was listed locally about 15 miles from my home and I just couldn't say no to it for the price and condition. It is an M116A2 chassis with a Power Plant AN/MJQ-33 body sporting two 3KW MEP-701A diesel generators. The forward generator has 69.5 hours and the rear generator has 140 hours. Both start and run beautifully with the center mounted transfer switch box working perfectly as well. They're already configured for 120V single phase and was owned by a HAM radio operator. He said he bought the trailer at auction in 2005. Pretty new lawn mower batteries (8/19), though only one pair wired to both generators. I can see that that would keep the maintenance cost down, but that does create a single point of failure. The trailer brakes work great and, surprisingly, the shock in the tongue is functional as well!

Here is the original sale ad photo for the generator trailer:



All the following pictures were taken after my short ~15 mile trip home. I was a little nervous at first as the tires are very cracked, but the fellow had an air compressor to add air to the tires (from ~20 & ~30 PSI to ~45 PSI). I traveled side roads home and didn't exceed 40 MPH. The return trip went well and my little '01 Dodge Dakota definitely enjoyed a trailer that provided it's own brakes.



I actually don't know the year but I'm calling it a 1990 based upon the contract number stamped on the tongue having "7-90" very prominent, a shop tag that was still in the tool box (Issue Date 11-19-90), and the date stamped in the CO2 fire extinguisher (5-91) (the fire extinguisher was removed for transport, since the cotton pads were rotten and it was loose in the mounting bracket). I don't know all the revisions the M116 chassis went through, but my understanding is that one way to tell an "A3" chassis apart from an "A2" (when you can't see the axle in the picture) is to look at the space above the shackle mount. The A3 frames are thicker (4") than the A1/A2 frames (3"). Well, this frame is 4", just like my M101A3 but it is clearly an A2. So 1990 would seem to fit it being a "late" A2 as I would not find it surprising if later model trailers, especially trailers going to support generators, received newer and thicker frames. This is just my presumptions.

CHASSIS, TRAILER, CARGO, 3/4 TON, 2W, M116A2
NATIONAL STOCK NO. 2330-01-101-8434
MODIFIED WITH HEAVY SPRING KIT 57K0912
MFD BY TURTLE MTN. MFG. CO.
VEH IDENT NO. 480
CONTRACT NO. DAAE0-7-90-C-J002

PUBLICATIONS
TECH MANUAL TM9-2330-202-14 & P

WEIGHT	EMPTY	LOADED
PAYLOAD	-----	2365
WHEELS	675	2880
LUNETTE	120	280
TOTAL	795	3160

DATE DELIVERY (blank)
INSPECTED (blank)




POWER PLANT AN/MJQ-33
2-DED, 3 KW, 60 Hz
NSN: 6115-01-280-2301
SERIAL NO.: T-91-126-22
TECH. MANUALS:
OPERATIONAL WEIGHT: 3160 LB
SHIPPING WEIGHT: 2850 LB ON LUNETTE: 200 LB ON WHEELS: 2960 LB
LENGTH: 147.30 IN WIDTH: 74.40 IN HEIGHT: 78.40 IN


US DEPARTMENT OF DEFENSE
3KW GENERATOR SET, DIESEL ENGINE
SERIAL NO. T-90-135-ASK-1853 MODEL MEP 701A
TM 5-6115-615-12/24P/34
NSN 6115-01-234-5966 (INCLUDES GEN SET
NSN 6115-01-150-4140 AND ACOUSTIC
KIT NSN 6115-01-271-1584)
VOLTS: 120/208 V 3 PH, 120 V 3 PHASE,
240 V 1 PH, 120 V 1 PHASE
DRY WT 532 LB L 44.00 IN W 28.5 IN
H 30.00 IN
MFR KIT TOBYHANNA ARMY DEPOT
INSP STAMP
30554-88-13603
MFR-14850


Same info as above, just:
SERIAL NO. T-90-135-ASK-1860 MODEL MEP 701A


Found inside the toolbox:
SHOP TAG
SERIAL NUMBER ITEM#01
WORK ORDER NUMBER T03N1D
ISSUE DATE 11-19-90
AMOUNT 1 EA
STOCK NUMBER AN/MJQ-33
NOMENCLATURE Switch Box Assy 13205E5079-5
ASSIGNED TO ELEC FAB
SECTION II
LEADMAN URBANSKI

 

[Valence]

Pictured above, the trailer came with a single, rusty, old style screw top jerry can, and below are the contents of the tool box with all the additional fuel hose that was packed around it, plus the CO2 fire extinguisher.

Note: Only seen in the right picture is a slightly bent up tan rod tan and rusty rod (above the fuel hoses). I assume it was a flag stake of some sort to mark where the grounding rod was placed.


On the left, an old fire extinguisher top handle.
The CO2 fire extinguisher surely needs to be recharged, and possibly hydrostatic tested. It is stamped "5-91" on the top.
Someone got lazy one day putting away the camouflage netting and threw a loose spreader/batton in this tool box. haha.
3 cut fuel line ends. Are the fittings reusable?


There are about 6 separate fuel lines coiled up here. I didn't uncoil them all.
The fuel lines are somewhat stiff and obviously sun bleached in places and filthy from sitting by the gen-sets on either side of the generator. collecting oil, fuel, dirt, debris, leaves, nests and etc. I'm not sure if I will use them. It may be best to have Evco House of Hose make new lines but that sounds pricey.
Notice the right most bundle has an attached aux. fuel jerry can attachment.


Two fuel spouts as well as two can aux fuel spouts (one pictured above). I used to have an NOS one that I sold, didn't think I'd ever use it, and well, here I am now. :"P
The original battery cables from the previous owner's single set of batteries modification.


Two NOS 90 degree fuel fittings
Two 1" cotton cinch straps
3 old flat nails
Fire extinguisher hook (top center, partially hidden by a fitting bag)


Misc home extension cords. The yellow one has been cut and is unusable without repair.
Also in the top right I believe is the grounding rod hammer. It had been left to rust in the weather at the front of the trailer.
Service tag at bottom right.


Some trailer plug harness adapter that I've never seen before.


What I consider a large number of copper grounding rods and a single twisted copper grounding wire with clamps. A couple rods are bet on top by the threads. One rod is very bent on the bottom tip with another's tip broken off.
And a random green washcloth.

 

[Valence]

Some of the bad things about the trailer:

As expected, it needs some TLC.

• Sadly it's 686 tan CARC over 383 green CARC -hahah, but none of my equipment is tan and I prefer woodland or solid 383 green.
• The center wood over the bows needs replacement, it's rotted beyond saving.
• I would need to buy a proper cargo cover. I cannot decide if I want a green or a tan cover. Though it does sound like a lot of work and more money to make the trailer and generators green instead of tan right now.

The transfer switch box needs new bulbs. I am not sure where I get these weird looking things. The left one surprisingly still works but it's extremely dim.


Unacceptable ground wiring, and grounding strap is in poor condition overall.


The electrical line out from the rear generator has had the outer wire wire coating damaged in this spot, though the internal wire sheaths look good.


As stated previously, the tires need to be replaced. I haven't yet searched what types of tires folks recommend.
BF Goodrich Trac Edge LT235/85R16 M+S
Load Range E

Right side:


Left side:



The tail light mounting brackets are bent quite severely, and a couple of the cargo cover loops too.

(I'm sure the shocks need replacing too)

There's also some bad tail light wiring under there too (unpictured).

I have yet to look up what these plastic footman loops were once used for, but otherwise it looks like an ideal spot for another jerry can, if I keep the trailer all together.

 

[Valence]

Honestly, I have considered disassembling this trailer and using the frame on my Pioneer Tool Trailer project, and keeping the generators and transfer switch box for home use. But the dang thing is complete and readily usable as is... I'm thinking of just leaving it. Gunzy has recommended that I keep it intact since transportable power can be extremely useful, and if you're good a packing, you can still load all kinds of stuff onto the trailer on and around the generators for transport.


What do you think?

 

[Tinstar]

I also would recommend keeping it together.

Great score!


It’s always the “other guy” who finds deals like this.

 

[Terracoma]

Some trailer plug harness adapter that I've never seen before.
View attachment 777368 View attachment 777379

That appears to be a plug end for the older style 2-pin slave cables. Erik's Surplus has this plug, for reference.

What I consider a large number of copper grounding rods and a single twisted copper grounding wire with clamps.

View attachment 777366

Looks like a great assortment of rods and connectors, and you did get a "drive stud" (attached to the 5th rod from the bottom in the above photo) that allows you to set the rods with a sledge hammer... I think an 8lb sledge is supposed to be part of the BII for the genny trailers? Not fancy, but works great.

The slide hammer is supposed to come with a steel rod (no copper cladding, extra long threaded section), and it looks like you also got a few of those... But you might be missing the collar/washer against which the slide hammer is applied. While no great loss for setting rods, they are helpful for removing rods.



Then again, I hear that setting the rods at an angle and strapping them to a HMMWV gets them pulled out quicker.

 

[Valence]

I noticed a fuel leak on the rear generator. It took me a while to get around to identifying and fixing the issue. It slowly leaked even while the generator was off. Running the generator made it easier to identify the source, then it was obvious to me how deteriorated the hose was.



It was #3 ("Hose 503-1055 (44940)) in Figure 18 on PDF page #65 of TM-5-6115-615-24P.


Unfortunately, I had to remove the top acoustic panel to gain access to the other end of the hose.


I sourced the replacement from a local place formerly called Evco House of Hose, now I believe it's "ERIKS North America". The fellow there matched the delapated hose with "H-HYD-FL-02" "Fuel Line Hose - 1/8 inch" and cost $2.38 per foot. I bought extra as well, if the line on one generator leaks, the other might soon as well or should get replaced as preventative maintenance. The hose seemed a bit small internally as I struggled to get it on the nipples but at least it's tight! As can be seen, I replaced the lower spring clamp with a worm clap as it was a lot easier to work with in the tight space.

 

[Valence]

This rear generator has exhibited another problem which I believe is a grounding issue on the frequency (HERTZ) gauge. While running the gauge will appear pegged, or maxed out (above 65 Hz) even though you can hear the RPM change when you adjust the Throttle knob.

In this video you can see the problem. The gauge is maxed out then starts operating normally and you can hear me increase the generator's RPM and see the Frequency adjust toward the middle (60 Hz). Shortly after the video cuts off the gauge maxed out again.

VOLUME WARNING: (the generator is loud for those of you maybe wearing headphones)
Sorry, it's not really in focus - it was dark and I had poor lighting for cell phone video.

I opened the gauge panel while the generator was running and measured the impedance (ohm) across both terminals and it was greater than my multimeter could read (assumed open circuit). Hence my reasoning that it's a grounding problem. I disconnected both wires and took a wire brush to each lead ring, washer, nut and threaded stud but it didn't seem to change the behavior of the Hertz gauge (stayed maxed out nearly all the time).



If it matters, the D/C voltage across the terminals on the Hertz gauge was 0.885v D/C (I assume it's a D/C gauge, but the A/C voltage was 0.009v AC)

Next I'll see if all connections are tight inside. I suppose I could swap the gauge with the front generator and see if the problem follows the gauge or not. Otherwise, I'm not sure where else to search on this one.

 

[Valence]

Update:

I haven't tried swapping the Hertz gauges yet, but I'm thinking there is actually nothing wrong with the gauge. I started up the front generator yesterday to show the generator to a friend and its Hertz gauge behaved the same. I let the generator run longer and the gauge started acting as I thought it should.

So I think the "issue" is just the operator (me) being impatient. Hah!

 

[Light in the Dark]

Frequency transducers are often at fault on the older air cooled sets for these issues.

 

[Valence]

Frequency transducers are often at fault on the older air cooled sets for these issues.

I'll have to go through the manual and find the P/N for one, buy and replace and see if that solves the issue. Thank you for the info!

 

[Light in the Dark]

I have some in stock. They are not the OEM unit (from another MEP) but they actually work well in this platform. Its just that the hole size is a little off (you will need to drill a couple new holes). $15/ea plus freight if you are interested. Just direct message me if so.

 

[Valence]

I've been a little MIA from the forum here, so let me get things caught up.

June 2nd, 2022:
I replaced the frequency transducer (Thanks @Light in the Dark!) on the rear-most generator and it seemed to help.


Here's a little operational test:

In taking off the side acoustic panel, one of the #10 stainless screws seized and the nutsert just spun so I had to drill it out. I didn't have a #10 nutsert, so I replaced it with 1/4". All screws/bolt replaced with anti-seize on the threads.


June 6th, 2022:
I replaced the very cracked tires with BF Goodrich KO2 LT235/85R16, for a cost of $550 at a local Discount tire. They looked so good on the trailer!


April 17th & June 9th, 2022:
I finally performed a full service: Oil Change, Fuel Filter, and Air Filter. I don't think any of them had been replaced since the military last owned it. The original oil filter read "Lubricating Oil Filter No. 122-0602". It was quite noticeable how much better both generators started and ran. Clean oil, fuel can get where it needs to, and they could breath properly. Imagine that!

The cork seal on the top of the fuel filter would fall apart to the touch.



New:
Oil Filter: Carquest 84026 (557026)
Fuel Filter: NSN: 4330-01-275-2460, MFG P/N: SAW-12752460
Air Filter: NSN: 4310-01-281-5988, MFG-76700, P/N 70307-A


Even though the replacement fuel and air filters were "NOS" and already ~20 years old, all seals, o-rings, and gaskets were still in great shape and a big improvement.

 

[Valence]

June 15th, 2022:
Both "Ever Start" batteries from 2019 still tested good. Rated for 230 CCAs and tested at 291 CCA and 265 CCA.


June 17th, 2022:
I made a very hard decision and sold the trailer and both generators. If I had a lot more money, I would have absolutely kept them because they're awesome and I loved the set up. But now that I had 2 MEP-803A (10KW) generators (and I still had my first MEP-016B generator), I couldn't justify having 5 generators.

According to the buyer, he was taking them out to be the primary sources of power for the construction of his cabin in eastern Nevada.

 

[Light in the Dark]

Good looking units, and I am sure the guy who bought them is more than happy. Nice!

 

[Guyfang]

Say Hi to Gunzy for me, the next time you see him. He lived across the street from us in 1971.

 

[Valence]

Good looking units, and I am sure the guy who bought them is more than happy. Nice!

It's nice to buy something fully serviced, fixed, and with no issues! Astute observers will notice I did keep items from the trailer. >.>
I couldn't leave my new trailers and generators without the handy pile of ground rods, slide hammer and more. ¯\_(ツ)_/¯

Say Hi to Gunzy for me, the next time you see him. He lived across the street from us in 1971.

It's been several months since I last saw him, but Mr. Gunzy is still around! Car-showing it up I believe.