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Unimog 406
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Discussion Starter #1
Hi there,
Does anyone know how many HPs a (UG 2/27) PTO delivers? Do both speeds (540 or 1000 rpm) deliver different HPs?
Cheers!
 

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unimog 406
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dear pelikan
if you have more speed you will loose more hp that means that if you have 50hp on the 1000rpm pto then you will have more or less 100hp on the 540rpm but you have to consider the load that you are apply to the pto you need to calculate the speed x the force divide by 380 and you will know how much power (hp) do you need for the att if you do desame formula and divide by 600 then you will have kw
 

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LAND ROVER 90 / DISCOVERY BOTH FITTED WITH TWEEKED PERKINS PRIMA ENGINES UNIMOG 404
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pto

if you want test figers check to see if there is a nabrasca test for your model ,i know there is for the 411 makes intresting reading.
 

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'78 Mog 416.141 DoKa
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3,404 Posts
Hi there,
Does anyone know how many HPs a (UG 2/27) PTO delivers? Do both speeds (540 or 1000 rpm) deliver different HPs?
Cheers!
The data book cautions you to not exceed a certain limit with certain drive shafts.

It says the max limit is 51KW (68.4HP) at either 540 -or- 1000 RPM when using 1 3/4" shafts or 1 3/8" volute profile shafts. The book cautions you to limit the power output to 33 KW when using 1 3/8" splined driveshafts at 540 RPM (OK to 51KW at 1000RPM)...

Now, as to the question, "Can the OM352 and UG2/27 actually deliver that kind of power ?", we have the following tidbit of data...

In the December 1979 edition databook, there are test stand results from a MB-Trac 442 (which uses the OM352 and a slightly re-geared version of the UG2/27). These results show actual delivered PTO power output of 68KW (92HP) when using a 110HP engine and 78KW (106HP) using a 125HP engine, both at 600RPM shaft speed. So, it appears the UG2/27 PTO drive is ~84% efficient at delivering the engines rated HP at that shaft speed.
 

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U1600AG + a LR 90
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995 Posts
the power-loss on the single or twin plate live/transmission 540/1000rpm PTO is 10%, i.e. if the engine flywheel outputs 100hp then the output at the PTO stub will be 90hp

NOTE:
if you are using "DIN" hp then an extra 5% error is automatically added to the 10% actual loss, DIN is absolute minimum HP, most other HP rating methods are average HP at rated speed.

its worth noting that HP is a notional number derived from force vs. distance vs. time (speed), i.e. 1HP is ANY force that equals 550lbf/sec or 33000lbf/min,
thus
1lb @ 550ft/sec = 1hp.
550lb @ 1ft/sec = 1hp
33000lb @ 1ft/min = 1hp
1lb @ 33000ft/min = 1hp

given this fact both the 540rpm & 1000rpm PTO will output the same HP when the PTO is run at the same rated engine speed, the difference is the 540rpm PTO gear will have almost twice the torque as the 1000rpm PTO gear as it is running at almost half the speed, in reality with Unimog if you are running the 540rpm PTO at exactly 540rpm & the 1000rpm PTO at exactly 1000rpm then the engine will be doing 2 slightly different rpm's thus outputting 2 slightly different HP
e.g. my pto gears are 4.08:1 (540rpm) & 2.32:1 (1000rpm) ergo PTO rated speed takes place at 2203rpm engine (540rpm) & 2320rpm engine (1000rpm)
 

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'78 Mog 416.141 DoKa
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the power-loss on the single or twin plate live/transmission 540/1000rpm PTO is 10%, i.e. if the engine flywheel outputs 100hp then the output at the PTO stub will be 90hp

NOTE:
if you are using "DIN" hp then an extra 5% error is automatically added to the 10% actual loss, DIN is absolute minimum HP, most other HP rating methods are average HP at rated speed.
Well, there you go - independent confirmation of my post.

10% loss + 5% correction for DIN HP = 85% efficiency vs. my average of 84

:thumbsup:
 
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