FAQ
TL;DR: Adjust through left-side 60 × 60 mm inspection window; set 8 mm (1st) and 12 mm (2nd) lever–bearing gaps. “First stage set to 8 mm, second to 12 mm” [Elektroda, FAB 2002, #16895721].
Why it matters: correct clearances stop slip, protect PTO and extend clutch life.
Quick Facts
• Old-type clutch: 3 release levers; new-type: 6 levers [Elektroda, sewo.k, post #16545900]
• Recommended gaps – old type: 4 mm (drive), 8 mm (PTO) [Elektroda, darekstrz, post #18182535]
• Recommended gaps – new type: 8 mm (1st), 12 mm (2nd) [Elektroda, FAB 2002, #16895721]
• Disc diameter grew from 224 mm to 225 mm after tractor No. 391570 in 1987 [Elektroda, BANANvanDYK, post #17534963]
• Two glow plugs sit in the intake manifold [Elektroda, piotrekwoj1, post #16545030]
Where exactly is the clutch adjustment window on an Ursus C-330?
Look under the diesel tank on the left side of the flywheel housing. A square ~60 mm window gives access to the release-lever locknuts [Elektroda, piotrekwoj1, post #16545030]
How do I tell whether my clutch is old or new type?
Count the release levers. Three levers mean the early design; six indicate the later, diaphragm-spring clutch [Elektroda, sewo.k, post #16545900]
What clearance values should I set on the old-type (3-lever) clutch?
Set 4 mm between pressure ring and bearing for the drive stage, then 8 mm for the PTO stage [Elektroda, darekstrz, post #18182535]
What clearance values suit the new-type (6-lever) clutch?
Use 8 mm for the first stage and 12 mm for the second, measured from lever tip to release bearing [Elektroda, FAB 2002, #16895721].
How do I perform the adjustment through the inspection window?
- Rotate the flywheel until a lever appears in the window.
- Loosen its locknut, then turn the inner nut until the feeler gauge (8 mm or 12 mm) fits snugly.
- Hold the inner nut and tighten the locknut. Repeat for every second lever until all six/three match [Elektroda, FAB 2002, #16895721].
Where are the glow plugs located?
Both glow plugs screw into the intake manifold just upstream of the head, one on each side of the centreline [Elektroda, piotrekwoj1, post #16545030]
Are C-330 and C-330M clutch discs interchangeable?
Not always. In 1987 the PTO disc diameter grew to 225 mm; fitting a 224 mm disc in a later tractor causes immediate slip [Elektroda, BANANvanDYK, post #17534963]
Why does my tractor stop moving with only slight pedal pressure?
Short pedal travel is normal; the first stage disengages drive in about 25 mm of pedal stroke. Ensure levers are level; uneven paws make the effect harsher [Elektroda, BANANvanDYK, post #20813190]
What tools and gauges are required?
A 17 mm ring spanner for locknuts, 8 mm and 12 mm feeler bars (400 × 35 mm, ends milled to thickness) and a crank bar to rotate the flywheel [Elektroda, FAB 2002, #16895721].
The clutch jerks after installing a new disc—possible causes?
Common faults: oil on linings, warped pressure plate, or mixed-type disc/cover. A 1 mm diameter mismatch raises surface speed 0.6 %, increasing grab [Elektroda, matigol96, post #20864947]
Can I improve the tactile separation between stages?
Stronger pedal return springs from a C-360 increase resistance between stages but raise pedal effort by about 25 % [Elektroda, piachu1994, post #20816981]
What size wrench locks the release-lever nuts?
Most covers use M10 nuts needing a 17 mm wrench; verify because some retrofit M12 (19 mm) hardware exists [Elektroda, piachu1994, post #17536799]
