1968, The second unified range:
A new standard in productivity

In the middle of the sixties, the demand for a heavy line of tractors for the individual farmer grew. The models UR1, with models of 25 to 58 hp, were insufficient for the grain farms of the Central European plains. In 1968, the development of a second Unified Range was completed. This UR2, better know as the Zetor "Crystal", had the high technical standards that were needed for large scale farming, such as hydraulic operated front wheel drive, powershift, and PTO, and came standard with the world's first safety cab with integrated roll-over protection structure mounted on silent blocks. The Zetor engineers pioneered a hitch hydraulic draft system with its sensors on the lower link arms, what was not seen on any other tractor in that era. The international press acknowledged that the Zetor Crystal raised the world wide technological standard to a higher level

The first UR 2 Crystals were the 8011 (2WD) and 8045 (4WD), introduced in 1968. They had the same 4.6 litre four cylinder engine, with a power of about 85 hp at 2200 rpm. It was an affordable tractor with a very wide range of standard features, and a high productivity, which made it a milestone in the history of tractor production.

The features Zetor offered as standard equipment, were optional on the products of competitors, or werent available at all. In official tests in Sweden 1972, the Crystal was the world's first to meet the N 85 noise level demands. The Zetor Crystal was way ahead of it's time, and the first generation was produced unalterated until mid eighties.

 

This new engine was a nephew of the Super 50 engine, the bore was widened up from 105 mm to 110 mm, and of course, the fuel injection was direct. Later on, a six cylinder UR2 Crystal, used the engine of the 8011 as base.The six cylinder engine had the same cylinder dimensions as the four cylinder, and had a displacement of 6.8 litre.

In the year 1978, Zetor began experimenting with turboblowers. the four cylinder engine was turbocharged to an output of around 100 hp and set on the market as 10011 and 10045. The six cylinder engine was also turbocharged, and performed 160 hp in the 16045. The turboblower was manufactured by Holset, type 3LD-12. These turbocharged engines had a apecific fuel consumption of 236 and 243 g/KwH. These measurements dont sound too bad, even in the current millenium !!

In order to gain more traction at a constant ploughing depth, The Zetormatic II hydraulics were pioneered. The classic weight transfer systems sensoring the top link arm, as invented by Harry Ferguson in the mid 30's, were not able to cope with the big multi-furrow ploughs the Crystal tractors were designed for. The top link sensor measures the pressure on the top link, caused by the implement leaning forward when it seeks depth. This works great with one, two or three furrow ploughs, but big ploughs are too long to lean forward, the working depth differs too much between the first and 4th, 5th or 6th furrow. Therefor, the Zetormatic II hydraulics were invented.

The sensors on the lower link arms measure the draft forces. When the force increases, oil is commanded to the hitch cylinder, to raise the implement a bit. But when the lower link arms are raised, the inclined positioned coupler arms, connecting the short main hitch arms mounted above the differential housing with the lower link arms, will overtake some of the draft forces. As soon as the draft forces decrease enough, the valve opens again, lowering the implement, again causing more draft force, and the working cycle is closed. The Zetormatic II is acting on force impuls, and not on the leaning forward of the implement, causing shorter reaction times, and thus a much more uniform working depth and better weight transfer.

8045

10011

12045

16045

[click on these images to view them full screen]

Zetor UR2 "Crystal" series

model

8011/45

10011/45

12011/45

16045*

production

1968-1987

1978-1987

1974-1987

1978-1987

type of engine

4 stroke OHV Diesel, liquid cooled, D.I.

engine model

Z 8001

Z 8002

Z 8601

Z 8601 Turbo

no. of cylinders

4

6

bore x stroke (mm)

110x120

displacement (cc)

4,562

6,842

power

85

100

120

160

aspiration

natural

turbo

natural

turbo

fuel cons.   g/KWh

269

236

?

243

nominal rpm

2200

transmission speeds

16 forward / 8 reverse

12 F / 6 R

(km/h) 1 L
2 L
3 L
4 L
1 H
2 H
3 H
4 H
1 R
2 R
3 R
4 R

2.3 - 1.8
3.7 - 2.8
5.9 - 4.4
8.5 - 6.3
6.9 - 5.2
10.9 - 8.2
17.9 - 13.0
24.7 - 18.5
3.3 - 2.4
5.1 - 3.8
8.1 - 6.1
11.6 - 8.7

2.4 - 1.8
3.8 - 2.9
6.1 - 4.7
8.7 - 6.7
7.1 - 5.5
11.3 - 8.7
17.9 - 13.8
25.5 - 19.6
3.3 - 2.5
5.3 - 4.0
8.4 - 6.5
11.9 - 9.2

3.0 - 2,2
4.9 - 3,6
8.1 - 6,1
--
9.3 - 7.0
15.3 - 11,5
25.5 - 19,1
--
3.5 - 2.6
5.7 - 4.3
9.57 - 7.2
--

torque multiplier

planetary, hydraulic clutches, ratio 1.3

PTO

540/1000, hydr. operated

hydraulics

Zetormatic II

control

Position/draft/mixed,
sensoring the lower link arms

max. lifting force (kg)

3400

4000

pump capacity

32 L/min.
150 bar

37 L/min. 
150 bar

remote outlet (scv)

1 double acting valve

Tires  2wd  front
4wd  front
rear

7.50-20
11.2/10 x24
16.9/14 x 34

9.00x16             NA
14.9/13 x 24
18.4/15 x34

trackwidth  (mm)

1500-1750 mm

weight       2WD 
MFWD 

3700
4150

3800
4240

4100
4870

n.a.
5270 (?)

* the 16045 was downtuned and sold as 14045 in some countries. 

 DmdB 2002-2003