Enough HP???

[Soundguy]

Your Ford/NH numbers sound optimistic at best. I've always used " the 14% rule " for geared tractors. When testbed numbers are not available from the manufacturer
1. subtract 14% from engine hp to get PTO hp
2. subtract another 14% from PTO hp to get drawbar hp

13.63% is close enough to 14 for me

//greg//

Those numbers don't seem to bear out on some of the Ford / NH product lit I have. perhaps it may be so for the compact range.. however once you hit ag and utility..( i.e., the higher you go in hp range ) it seems like the percentage is different on the ford/Nh models.

Soundguy

 

[diggerjim]

I remember something about the John Deere 4020 using around 14 hp to run the hydraulic system. IH tractors of the same size were able to outpull the 4020 (drawbar) load due to this. I would be interested to see factory specs on HP useage for the hydraulics systems, as this may be where the major loss comes from. Just my $.02.

I'd do the buy it and try it method, then sell it if it was too big a load.......

 

[slaveToHorses]

Hydrostatic transmissions do eat up more HP than a normally geared transmission. Even when you aren't moving, you loose a little HP because the engine still has to power the pump for the transmission. Just the price you pay for the convenience of the hydro.

The 14% rule is for net engine HP to PTO HP. Gross HP numbers are pretty useless.

 

[Farmwithjunk]

I remember something about the John Deere 4020 using around 14 hp to run the hydraulic system. IH tractors of the same size were able to outpull the 4020 (drawbar) load due to this. I would be interested to see factory specs on HP useage for the hydraulics systems, as this may be where the major loss comes from. Just my $.02.

I'd do the buy it and try it method, then sell it if it was too big a load.......

John Deere increased HP on PowerShift 4020's by a whopping 3 HP to overcome the power loss due to running the pump. The pump didn't actually power the tractor. It was used to provide power for SHIFTING the transmission. Clutch packs made the actual mechanical connection in the tranny. It wasn't a hydrostatic tranny, but a hydraulicly shifted one.

IH 806 would, in some cases, outpull the first 4020's because it was (a) heavier, and (b) had more torque.

Later 4020's (1969 through 1972) were a draw against a stock 806. Both were superb tractors in their heyday.

I never put a lot of stock in the numbers from either manufacturer on those tractors. Back in the day, it was a rare instance when a 4020 OR an 806 would dyno at anything like stock "rated HP" when the dealer dropped it off at the farm.

 

[AndyMA]

Bob

I'd still hand it on your TN. You obviously won't even notice the weight and you'll have plenty of hp for all but the heaviest, wet, sticky snow at high speed. Just wax it up, take a smaller bite and slow down a little.

Andy

 

[AndyMA]

And BTW, the TN engine has a large (34% in mine) torque reserve to handle sudden increases in power requirements.

Andy

 

[Doc_Bob]

Bob

Just wax it up, take a smaller bite and slow down a little.

Andy

How do you wax it?
Bob

 

[dgl24087]

TN70DA is still NE Tested at near 60 PTO. http://tractortestlab.unl.edu/NewH/TN70DA.pdf

 

[rambler]

When I went to buy a snow blower, the dealer kinda just threw up his hands at hp recommendations. Type of snow & your reverse gears available have _lot_ more to do with it. Aslo, you _need_ a live pto....

I have a 7 foot snow blower, 2-stage single auger - sticker says 40hp blower. I run it on my Fords 7700 (85 hp, 4 speed reverse), 960 (~45 hp, 1 speed reverse) and my NH 1720 (~23 hp, 3 reverse) and you know what? All 3 of them will pull it. Just fine. Depending on the snow type, all 3 will fill it up & I will need to stop moving & let it clear. The big 85 hp tractor plays with the blower, but I don't get more done for all that excess hp. The little 23hp tractor is the most fun to use with it - the least power, but by far the most nimble. The single-speed reverse tractor is the least fun.

I don't see hp as that big of a deal on a snow blower - if you have real slow reverse gears. I think you are close enough to the ball park to give it a try.

--->Paul