12v vs 115v hydraulic power units and hydraulic semi trailers

I have a 12v hydraulic power unit similar to this one:
http://goo.gl/UpLJG
The application (what I am trying to accomplish) is to operate this
hydraulic beavertail semi trailer:
http://igor.chudov.com/tmp/Trailking/Trailking-0009.jpg
When OI think about using this pump, I become concerned that it is operated by a starter-type 12v motor and is desighed for pick-up truck liftgates or snowplows, that is, very intermittent duty.
This beavertail trailer, while also essentialy intermittent, takes a lot more work per unit of operation (pull beavertail lock, pull extension lock, raise tail, extend extension, lower tail). That would take this little motor a long time and it may overheat and burn out.
Is my concern justified?
I have a few options for powering this trailer. I am basing this on my assumption that all cylinders are double acting, so not a lot of fluid is needed.
The options are:
1) Install a truck wet kit. cost: $2,000.
2) Use a 12v hydraulic pump that I already have. Cost: Small $$ for wiring. 3) Use a 115v, self contained power unit that I purchased yesterday along with a hydraulic H-press for $195. I would take along a Honda generator that we have to run this pump. Cost: $195, minus whatever $$$ I can get for the press without the hydraulic pump,and the four way manual valve.
This is a 1.5 HP unit with a continuous duty Marathon motor.
The plus of number 3, as I see it, is that the 115v hydraulic power unit there, is not intermittent duty, and could do the job, with less financial risk than plopping down $2,000 on a real wet kit. It would be slower to work the tail cylinders than the wet kit, due to less horsepower, but it is not a big deal. It will, however, cost me extra $5 every time the tail is operated, to pay extra hourly salary tot he operator.
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Ignoramus25949 wrote:

The wet line kit for the tractor is the proper way to do it of course and $2k isn't much in relation to the other costs related to the semi and trailer.
I have seen a Landoll hydraulic everything trailer that was powered by an onboard hydraulic unit run by a small diesel engine like a 3 cyl Kubota.
I would consider a small gas powered setup, basically just an 8hp gas engine coupled to a gear pump and a tank just like a log splitter setup. You wouldn't have any duty cycle issues, the trailer could be operated without the tractor if needed and it should cost perhaps $750 to put together.
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The semi tractor cost me $2,300. I am reluctant to double its cost with a wet kit.

Yep, so have I.

My choice number 3 is almost what you are describing, except that there is a generator and an electric motor in the middle. Like I said, I already have a portable Honda generator, and since yesterday, have this single phase 1.5 HP hydraulic power unit.
i
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Ignoramus25949 wrote:

Personally I wouldn't want to put the extra hours on a good generator like that. I'd rather pickup the few parts to assemble the basic gas hydraulic power pack.
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On Sun, 29 Apr 2012 20:07:30 -0500, Ignoramus25949

Do the cylinders on your trailer use more than a gallon? You will need a valve, extra hoses, heavy duty battery cable to the trailer, and likely a larger reservoir, so this isn't as cheap as it seems.

Oh, OK. Scratch the reservoir.

I like #3 a lot, but what about a #4?
4) Mount a small gas engine and hyd pump with reservoir, creating a local power unit usable anywhere? Cheaper than #3?
HF for the littlest Predator engine ($119), Burden Surplus for the pump and valving ($250, 2spl DA), and maybe a tank, if you don't weld up your own. http://tinyurl.com/7pxq2y9 engine http://www.surpluscenter.com/item.asp?Item=9-8239-L 15.5gpm pump (7x faster than the 12v model)
-- You never hear anyone say, 'Yeah, but it's a dry cold.' -- Charles A. Budreau
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True. Keep in mind though, that most cylinders there are double ended, and those do not need a big reservoir.

Plus filters, belts, pulleys, mountings etc
In my experience, such projects end up very expensive and time consuming. Plus I do not trust HF engines, but I do trust Honda.
And all those surplus things at these surplus centers have some fatal flaws that make them somehow unusable for normal applications. (which is why they ended up at those surplus centers, cannot be sold through normal channels)
I am not trying to be difficult, just stating my past experience. Say, this hydraulic pump's description says "pump to operate hydraulic wheel motors on zero turn radius equipment applications including turf, light construction and other mobile equipment". What exactly it means, I am not sure, but it makes me slightly suspicious of whether this is a general purpose pump.
i
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On Sun, 29 Apr 2012 22:20:11 -0500, Ignoramus25949

Direct mount the pump to the engine, no belts or pulleys needed.

Grok that. I saw that you already have the genset and power head, so make sure to document it. I'd like to see it when you're done.

I thought they were just NOS overages and misbuys by companies.

I haven't bought much from Burden, but everything I have has worked. No hyd, though.
-- You never hear anyone say, 'Yeah, but it's a dry cold.' -- Charles A. Budreau
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Ignoramus25949 wrote:

Not TRUE. The surplus outfits buy the left-overs and oddball items that the companies just want to clear out of inventory. Plus items that were bought in large quantity then were not used.

Well for a cheaper way would be to hunt up a smallish wood splitter and swipe the engine and pump off it along with the small reservoir.
--
Steve W.

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message

They may have an involute splined shaft that you can't find a pulley or coupler for, and have to make it like I did.
The replacement keyed shaft hydraulic pump I bought from Bailey's for $80 has been OK so far.
The 11 GPM log splitter pumps take a 5 HP gas engine.
You could monitor the 12V pump with an infrared thermometer and an ammeter while you made tests. I modified a battery charger into an adjustable 12V supply and used it to check out the HF 12V bilge pump yesterday. I bought the pump to water my lawn from the rain barrels. It doesn't seem to mind a high back pressure and flow restriction.
jsw
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Ignoramus25949 wrote:

No belts or pulleys, direct coupled hydraulic pump. Mounting is just the four base holes on the engine. A return line filter is cheap. The trailer already has the valving, so all you need is a small tank and some hoses.

Those engines are pretty decent clones of the major brands and seem pretty reliable. Buy a second for the $120 and have it on hand for a quick change if needed. Changing it would be some 8 bolts and 10 minutes.

They aren't surplus, that is just the name of the company. at least 75% of the stuff they sell is new.

It will be a brand new Barnes two bolt mount two stage pump, not some surplus oddball.
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Ignoramus25949 wrote:

The motor may look similar to a car starter, but is designed for hydraulic pump service. You'd certainly get in trouble using it for real continuous duty, but I'd think running it for several minutes would not cause overheating.
Does your semi have a 12 V electrical system? Over the road semis usually have a 24 V system, but intra-city semis can have a 12 V system.
I'd think having to haul an AC generator around would just make everything more complicated.
Jon
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Jon Elson wrote:

According to the specs I've found, standard duty cycle versions are 24sec on in 5min, and the extended duty ones are 39sec on in 5min. Several min under full load and they're melting.
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Would not work for me...
i
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On Sun, 29 Apr 2012 20:07:30 -0500
<big snip>

Something like this:
http://fosterhydraulics.com/page/gas/complete_hydraulic_trailer.html
A local trash/container hauler has something very similar on his haul trailer. It has a radio remote control. Goes something like this; starts the gas motor, leaves his truck in neutral, adjusts the tilt on his trailer to the container via remote while standing right by it, either hooks/unhooks winch cable, uses remote to control winch and or hydraulic tilt on the trailer... Works really slick too...
More than you want to pay, but it has a nice parts list showing you everything needed...
--
Leon Fisk
Grand Rapids MI/Zone 5b
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Way too expensive, I can have a real wet kit for this kind of money.
i
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