Cattini Oleopneumatica YAK 221/N, Operating And Maintenance Manual

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A00423 A00423 , then repeat the bleeding operation illustrated on the previous page. Put the jack back into its normal position
and reopen the tap.
- Check the hydraulic block
POS. 2 A00543 POS. 2 A00543 , paying special attention that the piston pos.4 of the A00324 exploded
drawing which controls opening and closing of the descent valve pos.7 of the A00324 exploded drawing, has not
become rigid, in which case dismantle and grease it.
THE JACK LIFTS, BUT COMES DOWN UNDER THE LOAD.
- Dismantle the assembly POS. 2 A00543 POS. 2 A00543 and check that under the bearing POS.7 A00324 POS.7 A00324 there are no impurities.
After carefully cleaning, readapt the pin POS.7 A00324 POS.7 A00324 in its seat with a light blow with a hammer. If the load still falls
even after fitting the jack, carry out the following step. - There is dirt underneath the valves: remove the casing, close
the tap
POS. 9 A00543 POS. 9 A00543 , turn the jack over so the cylinder is horizontal and the motor pump vertical, loosen the cap
POS.16 A00423 POS.16 A00423 , remove the bearings and springs and blow inside to thoroughly clean it. Reassemble and if
necessary knock again the bearings POS.12 AND POS.14 A00423 POS.12 AND POS.14 A00423 , then repeat the bleeding operation illustrated on
the previous page. Put the jack back into its normal position and reopen the tap.
- Completely drain the tank and the cylinder of oil, loosen the cylinder and check the washer
POS. 7 A00367 POS. 7 A00367 . If it is
damaged, replace it. Refit everything being careful not to let the replaced seal fall between cylinder and base. Fill the
oil tank with oil to the required level; operate the jack a couple of times without the load; bleed and then top up the oil
level when the pistons are lowered.
THE RAMS FAIL TO GO BACK IN COMPLETELY EVEN WITH THE CONTROLS IN DESCENT
POSITION.
Check the suction-pump POS. 22 A00423 POS. 22 A00423 : remove it and clean it thoroughly.
- Check the head, POS. 19 A00423 POS. 19 A00423 , remove it and clean it thoroughly.
OIL LEAKS FROM THE SILENCER POS. 3 A00423 POS. 3 A00423
- Check that the pumping element pos. 11 of the A00423 exploded drawing is not scored or damaged. If it is, replace
it.
- Check that the seals,
POS. 5,6,9 A00423 POS. 5,6,9 A00423 are not worn. If they are, replace them.
OIL LEAKS FROM THE SUCTION PUMP POS. 22 A00423 POS. 22 A00423
1. Check the quantity of oil in the tank, (see the “Oil level check” procedure in the "Maintenance for the end user”
section). If too much oil has been put in the jack, it will stop leaking very soon.
2. Check that the jack has been used observing the conditions listed previously, i.e. horizontally and not slanted. If the
jack has been turned upside down or tipped over, it will stop leaking very soon.
THE PISTONS ARE VERY SLOW TO MOVE UP
- Check that the tap, POS. 9 A00543 POS. 9 A00543 , located between the tank and motor pump is open.
- If the jack malfunctions when moving up, check the spring POS. 17 A00423 POS. 17 A00423 .
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