the guide rod and the cylinder head seal housing bore

the piston rod and the cylinder head guide sleeve gap due to long-term use , the guide portion grinding round loss , injury, or gap gap increases film destruction is caused by the piston rod seal leakage of the main factors . In this state , even if the replace with new seals , pressure oil from the piston rod will produce at the external leakage symptoms assembly of all seals , the material must meet the standards. Y-shaped , V-shaped , U-shaped seals , etc. , may not have the appearance of uneven quality ,Hydraulic tube fittings  impurities, bubbles, scratches and other defects burr burr , dust ring into the piston rod may not have bite wounds , otherwise it will lead to fuel tank leaks .chrome plated piston rod surface layer may have fallen off or serious irregularities at the piston rod bending deformation , shall meet the design requirements : the piston rod surface is 1000mm straightness of less than 0.3mm, available instruments to measure checks. Construction site inspection , the available head is not installed seal coating of hydraulic oil into the guide sleeve on the piston rod , and then full stroke reciprocating sliding and rotating , feel no gap is appropriate.