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Unimog U1200 full ag specs, CLK500
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Discussion Starter #1
I am looking at a 406 Pre-SEE 82 and I am wondering how difficult it would be to have a front or back (or both) PTO added to it. As far as I can tell it has a PTO, however it currently drives a hydraulic pump. Does anybody know if this is an addional hyd. pump which was used for the backhoe and if I remove it will I still have the "normal" hydraulics?
What other differences are there to a normal 406 ?
THANKS
Johannes
 

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BenzWorld UNIMOG statesman
Unimog 404.1 Diesel (sold :( )1995 LMTV 1078
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hmmm. now this is a tuff one to search for. We do have a thread or two in here on the very topic of what your calling a Pre SEE.

try searching using some of the below at key words:

SEE 406
SEE Case
"Pre SEE"
 

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BenzWorld UNIMOG statesman
Unimog 404.1 Diesel (sold :( )1995 LMTV 1078
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BTW... when you say will ask will it still have have "normal" hydraulics do you mean for brakes, power steering etc.... if that is your question it is easily answered. Look under the hood for a power steering pump.

Though Im very sure the answer is yes... pto pump only ran the implements. Think about it... there would be no PTO disengage if it was used to power the brakes and power steering and like looking for a power steering pump under the hood.... odds are in the cab if you look you'll see that it does have a PTO selector.
 

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a couple round ones
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Well not being a SEE guy or a 406 guy for that matter, I will take a shot in the dark and say anything running off of your PTO is an ''extra'' .
As coachgeo said "pto pump only ran the implements". For the most part if you have 'basic' hydraulics they are run from a belt of off your engine and the lines can go front/rear/sideways...
Others have a hydraulic pump of off the PTO, front/rear...you get the picture.
Tons of variation and set ups, but to answer your initial question about removing the pump from the pto, go for it.
As to adding an additional PTO shaft , same as above...go for it.
G Vavra
Again...take all this with a grain of salt.
 

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1973 416 Doka, 1978 416 Doka, 1980 416 Doka..... Help me, I can't stop buying them!!!
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The 406 has at least Five different PTO's that I can think of right off the top of my head. But I bet the factory has a few more. There are two high speed (3000 RPM) that are just for hydraulic pumps. One is on the cascade box, and you can't add a front/rear PTO with this set up. You can remove the hydraulic pump, and then add the other PTO. The other hydraulic set up is on the bottom of the transmission, and a front/rear PTO can be added.
 

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Unimog U1200 full ag specs, CLK500
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Discussion Starter #7
3000 RPM PTO output

Hi Von,
great info!

Meanwhile I also found out that the belt driven hydraulic pump was removed, but can be added again. It has a separate oil reservoir, so the unit has 2 independant hyd. systems IF the belt driven pump is installed.

There are two high speed (3000 RPM) that are just for hydraulic pumps. One is on the cascade box, and you can't add a front/rear PTO with this set up.
How do I tell just by looking at it that this unit has a 3000 rpm PTO?
I will try to take some pictures, maybe that helps.

Thanks to all for the help so far.
 

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BenzWorld UNIMOG statesman
Unimog 404.1 Diesel (sold :( )1995 LMTV 1078
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What is your plans with this truck? Would help to know that.

BTW- please consider that you have a VERY RARE BIRD. While Im all for using your Mog the way you want.. there are a few exceptions and the rarity of this Mog does seem to make it one of them, at least in my book. Please consider not straying to far from it's orginal set up.
 

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'88 U-1300L, '70 406, '78 406, '78 416 project, '82 406, '57 404, '65 404, '70 404, '68 Haflinger.
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Would be fun to see some pictures of that truck!

Based on what you asked, and what you told us, sounds like the 406 has the high capacity hydraulic pump under the transmission. The hydraulic reservoir would be behind the cab and between the rails of the Case deck. You might confirm.

The "pre-SEE" 406's did use that underslung PTO/pump to run the backhoe, but the front hydraulic system ran the front loader, if it had one.

You specifically asked about adding front and rear PTO. The 540/1000 rpm shiftable PTO (or single speed 540) mounts on the opening on the left side of the transmission. If that Unimog has a flat cover plate on the left side, then the PTO can be added. Those PTO boxes can be found rather easily. The shafts can also be found but smaller (fits most implements) 1-3/8" x 6 spline is the rarer of the two spline sizes. No matter what the truck has for hydraulics, you can add those front and rear PTO shafts with $$$ expenditure. Bet Von has the complete setup.

The hi-cap hydraulic system can be used for anything you want to do, but, you have to add the control spools to do it. That system relied on the implement (like backhoe) to have the valves/spools to do the controlling. Get to know how an open-center hydraulic spool rack works because that's what you'd need.

Even without hydraulics, but with PTO's, you can use 'drag-behind' implements. I use a big brush cutter that hooks to rear drawbar and is PTO powered and no hydraulics needed.

As you know, to have the convenience of the front hydraulics (if you find a replacement pump), you have to have the controllers normally installed on the steering column and under the hood (does that truck still have those?). Anything can be added but to replace the entire front system, control/spools, plumbing, etc, would be a big job.

IMHO, if use of a 'tractor' with PTOs and full hydraulics is your main goal, I'd recommend looking for a complete 406 ag-spec, or Case MB-4/94 (common here in the States).

Bob

I am looking at a 406 Pre-SEE 82 and I am wondering how difficult it would be to have a front or back (or both) PTO added to it. As far as I can tell it has a PTO, however it currently drives a hydraulic pump. Does anybody know if this is an addional hyd. pump which was used for the backhoe and if I remove it will I still have the "normal" hydraulics?
What other differences are there to a normal 406 ?
THANKS
Johannes
 

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Unimog U1200 full ag specs, CLK500
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Discussion Starter #10
406 Pre-SEE

Hi Bob,
yes I can confirm that the hydraulic reservoir is the cab and between the rails of the Case deck.
There is lots of snow so I was unable to take good pictures. Will try to get this mog into a heated shop in the next little while. We have -25C here right now...
Meanwhile some pictures with snow:





Johannes
 

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'88 U-1300L, '70 406, '78 406, '78 416 project, '82 406, '57 404, '65 404, '70 404, '68 Haflinger.
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I have been reminded in a PM that I know that truck, LOL. I'm just too slow to pick up on that fact!

I got to look it over when it left West Virginia a couple of years ago. It's a good solid truck that needed some TLC at that time.

Yes, it has the Hi-cap hydraulics with the pump under the tranny. The tank and filter system is different from a Case MB-4/94 but looked perfectly functional. I liked the external filters (ie, not inside the reservoir which is a real PIA to work on on the Case units).

It also has the standard hydraulic system up front and if I remember correctly, it's complete except for the hydraulic pump that had been removed for repair and not put back. Would be an easy fix to get it going...a replacement pump, good purge of fluid, replace filters, refill.

Those two control handles on the left rear of the Case deck are rarely found, I think. Those control the lift of the bucket on the front, and the throttle. Very handy when operating the backhoe.

You should ask the current owner all these questions :) He knows this truck very well.

Those other threads posted earlier have good info in them.

Hi Bob,
yes I can confirm that the hydraulic reservoir is [behind?] the cab and between the rails of the Case deck....chop....
Johannes
 

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250GD Wolf
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I know the current owner and have had dealings with him, I can vouch he's a solid guy to deal with, and doesn't skimp on repairs, you'd be buying a solid truck from an honest seller.

-Trev
 

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Unimog U1200 full ag specs, CLK500
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Discussion Starter #13
Pre-SEE

Hi guys,
yes the owner is a good guy, no question and I did ask him all these questions. If I can or cannot easily add PTO outputs to front and back was the question he could not answer either, so as mentioned I am trying to get this truck into a heated shop so I can actually take a good look. And yes it still needs TLC...

Bob do you remember if the PTO driving the pump is a 3000 RPM PTO?
I also heard from a 406 owner in Germany that not all PTO setups allow the full horsepower to be used on the PTO. One of my potential uses could pull up to 100 hp (short period) from that 540 PTO. This unit has 110 hp, so it should be ok... or not?

Thanks,
Johannes
 

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U1600Ag
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I also heard from a 406 owner in Germany that not all PTO setups allow the full horsepower to be used on the PTO. One of my potential uses could pull up to 100 hp (short period) from that 540 PTO. This unit has 110 hp, so it should be ok... or not?
You should PM our resident mathematician B101uk for the %loss between engine and PTO HP.

He knows his shiite.
 

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'88 U-1300L, '70 406, '78 406, '78 416 project, '82 406, '57 404, '65 404, '70 404, '68 Haflinger.
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The 'lower PTO' (term used in the manual) with hydraulic pump is rated at 3400 rpm and that's probably at max engine rpm (typically 2550 to 2700 rpm for various years of OM-352 engine). No HP rating listed.

I think the term 'fast PTO' (as used in manual) specifically refers to a side-mounted PTO mounted to the cascade housing. The rating on the 'fast PTO' is 3000 rpm. No HP rating listed.

I have not found the horsepower ratings of these PTO's in the manual. It's my understanding that the 'lower' PTO and 'fast' PTO's are not rated anywhere near the rating of the main 540/1000 PTO, which, I think, has a 75 hp max rating. Ratings are usually honest ratings though so that's probably 75 hp continuous.

That agrees with your info that the PTO's are not rated to handle full engine HP. You might be able to load the 540/1000 rpm PTO higher than 75 hp for short terms, but, if there are any shock loads involved, I certainly would not do it.

Might I ask what load you want to run to full engine HP? Some implements like a chipper, silage chopper, large rotary cutter (Bush Hog) sure do create shock loads.

I've had instances where the tranny sounds like it's going to explode if the rotary cutter hits a stump, etc, eventhough there's an overload clutch in my driveline. I mention this because operating any machinery at or above rating is risky. If you really need over 100 hp in a PTO, good luck.

When higher PTO power is needed, Mercedes typically provides an auxiliary engine, as for snow cutters and blowers.

BTW, most OM-352's are not rated more than 74 kW, about 100 HP. Typically they are less. You could get the engine number and let someone look it up for you.

Bob

Hi guys,
yes the owner is a good guy, no question and I did ask him all these questions. If I can or cannot easily add PTO outputs to front and back was the question he could not answer either, so as mentioned I am trying to get this truck into a heated shop so I can actually take a good look. And yes it still needs TLC...

Bob do you remember if the PTO driving the pump is a 3000 RPM PTO?
I also heard from a 406 owner in Germany that not all PTO setups allow the full horsepower to be used on the PTO. One of my potential uses could pull up to 100 hp (short period) from that 540 PTO. This unit has 110 hp, so it should be ok... or not?

Thanks,
Johannes
 

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Unimog U1200 full ag specs, CLK500
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Discussion Starter #16
Pre-SEE

Thanks Bob!

This unimog would have farm use and most PTO applications I have in mind are less than 70 hp, however I also have a 13" 81' auger which moves grain. Typically I have a tractor in front of it, but I would like the unimog to be a possible backup. There won't be any shockloads, as you only get to 100 hp or so when you open the grain chute too much, typically the engine would gradually be loaded down and worst case scenario would quit. If the operator pays attention he closes the chute and the engine recovers.

Maybe I need to rethink my use or look for something like a U1500 ?

Johannes
 

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Would be fun to see some pictures of that truck!

Based on what you asked, and what you told us, sounds like the 406 has the high capacity hydraulic pump under the transmission. The hydraulic reservoir would be behind the cab and between the rails of the Case deck. You might confirm.

The "pre-SEE" 406's did use that underslung PTO/pump to run the backhoe, but the front hydraulic system ran the front loader, if it had one.

You specifically asked about adding front and rear PTO. The 540/1000 rpm shiftable PTO (or single speed 540) mounts on the opening on the left side of the transmission. If that Unimog has a flat cover plate on the left side, then the PTO can be added. Those PTO boxes can be found rather easily. The shafts can also be found but smaller (fits most implements) 1-3/8" x 6 spline is the rarer of the two spline sizes. No matter what the truck has for hydraulics, you can add those front and rear PTO shafts with $$$ expenditure. Bet Von has the complete setup.

The hi-cap hydraulic system can be used for anything you want to do, but, you have to add the control spools to do it. That system relied on the implement (like backhoe) to have the valves/spools to do the controlling. Get to know how an open-center hydraulic spool rack works because that's what you'd need.

Even without hydraulics, but with PTO's, you can use 'drag-behind' implements. I use a big brush cutter that hooks to rear drawbar and is PTO powered and no hydraulics needed.

As you know, to have the convenience of the front hydraulics (if you find a replacement pump), you have to have the controllers normally installed on the steering column and under the hood (does that truck still have those?). Anything can be added but to replace the entire front system, control/spools, plumbing, etc, would be a big job.

IMHO, if use of a 'tractor' with PTOs and full hydraulics is your main goal, I'd recommend looking for a complete 406 ag-spec, or Case MB-4/94 (common here in the States).

Bob
Hammogger - do you have photos of your pto driven brush cutter? I would like to reconfigure the Case MB4/94 (1973) to do brushcutting but I mounted the Case three point hitch and lost the pto ability without the adapter (plus the tight spacing on the three point. Thanks!
 

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U-1300, 3 ea 406, 3 ea 404, Haflinger, 2 ea LMTV.
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That was a long time ago :) I eventually upgraded to a Case 3-point adapter and a PTO centralizer. The old mog hitch setup is no longer in existence, but I can describe it. No pictures that I can find of the back of the mog but I could take pictures of the old mower which is still sitting out in the equipment yard.

Assume basic Unimog with nothing on the rear of the frame. Need to fabricate a drop-hitch to provide a connection point for the drag-behind mower. I used existing bolt holes at the center of the rear cross member and lowered the hitch point about a foot. The PTO on the mower is centered, the Mog PTO is not, but, it does not matter. My mower set far enough back that the PTO shaft did not make too great an angle. That did require a long shaft though, so not ideal. Another idea I used was to put the hitch point below the PTO output, offsetting the whole mower. That worked very well because the offset was to the drivers side and the mower was offset in such a way that mowing along a fence was facilitated, if that makes sense. I actually miss that old, simple setup, but now have a 3-point mower lifted by the 3-point adapter.
 

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That was a long time ago :) I eventually upgraded to a Case 3-point adapter and a PTO centralizer. The old mog hitch setup is no longer in existence, but I can describe it. No pictures that I can find of the back of the mog but I could take pictures of the old mower which is still sitting out in the equipment yard.

Assume basic Unimog with nothing on the rear of the frame. Need to fabricate a drop-hitch to provide a connection point for the drag-behind mower. I used existing bolt holes at the center of the rear cross member and lowered the hitch point about a foot. The PTO on the mower is centered, the Mog PTO is not, but, it does not matter. My mower set far enough back that the PTO shaft did not make too great an angle. That did require a long shaft though, so not ideal. Another idea I used was to put the hitch point below the PTO output, offsetting the whole mower. That worked very well because the offset was to the drivers side and the mower was offset in such a way that mowing along a fence was facilitated, if that makes sense. I actually miss that old, simple setup, but now have a 3-point mower lifted by the 3-point adapter.
Thank You! I believe I understand what you were doing. I will have to find a way to fashion a linkage for accomplishing the task! Blessings!
 

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I have a pre-SEE also. I heard somewhere that there were 9 made (and maybe two different engines among those 9?). It's a '61 (per the title) that was modified and now has a 12/31/1982 delivery date and an 82 on the VIN. One unique thing, that I haven't noticed on any other mog, is that the front and rear tires are different widths. The rear ones are 405-70 and the front are 12.5-20. No PTO on the front, rear runs the aux hydraulics. Also, it's 24 volt.
 
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