Morehouse UCM - Service Instructions for Hydraulic Hand Pump; Repair

Universal Calibrang Machine
(UCM) Manual
(PM-5201)
Morehouse Instrument Company, Inc.
1742 Sixth Ave., York, PA 17403-2675 USA
Phone: (717) 843-0081
www.mhforce.com
Page 35
Rev. 3/2024
6.3 Service Instrucons for Hydraulic Hand Pump
When changing O-rings, always lubricate the O-rings and all contacng metal parts before aempng assem-
bly. For a lubricant, use the same uid as will be used in the system. The high-pressure valve and retaining
parts are held in place by the retaining plug (57). To reassemble, screw the retaining plug (57) into the body
unl all parts are solid, then back it o about two turns. This provides sucient travel for the poppet.
The valve rod (41) is held in place by three parts (25, 26, and 27) that must be removed to enable disassembly
of the valve rod. Access to these three parts is gained by removing the reservoir (2). Drain the hydraulic uid
before removing the reservoir. The piston and hand lever can be removed as an assembly. Unscrew the cylin-
der retaining plug (16), disconnect from the clevis (19), and pull straight up. At the end of the pressure stroke,
the piston should boom on the body plate (50) before the lever hits the cylinder retaining plug (16). If it does
not, or more nger room between the hand lever and reservoir is desired, loosen the piston pin (7), insert a
small rod in the cross hole provided in the piston, and back of the piston, which is threaded into the piston pin
(17) as needed. Re-ghten the setscrew (7).
The cylinder pump (18) must be removed and reassembled from the top. If it is not, the O-ring will be cut by
the angular, intersecng body casng bore. To remove the cylinder, detach the body plate (50) and push the
cylinder from the boom. On reassembly, lubricate the O-rings and try to rotate the cylinder, as inserted, to
avoid cung or pinching the O-rings. A tapered piece of wood is helpful in rotang the cylinders.
The precision pressure adjustment mechanism can be unscrewed from the pump body as a unit. The star
wheel (21), star wheel pin (22), piston cap (23), and piston (24) make up a sub-assembly, which is removed
from the pump body by unscrewing the piston body (24). Note that the star wheel (21) is aached to the Ver-
nier piston (58) by means of a pin (22).
6.4 Repair
All parts of the calibrang machine, except O-rings, are designed to last indenitely in normal use. If inadver-
tent misuse or accidental damage occurs, the damaged parts may be replaced to repair the machine.