Preparation of lapping paste:
The paste is diluted with test liquid or diesel fuel to a liquid consistency so that when the tip of the lapping is lowered into it (1.5 -2 mm), not a large "ball" with a diameter of 2-3 mm is formed on it.
The consistency of the paste must be constantly monitored and timely mixed for homogeneity.
Install the valve holder on the moving table of the machine by first lubricating the base with oil to prevent unnecessary vibration.
To set up a movable table of the machine. When it is set, it is necessary to ensure that the free stroke of the cartridge (by pressing and releasing the handle on the top or side) from the center of the multiplier to the lapping is 2-3 mm.
Apply a small amount of lapping paste to the centre of the valve seat.
When installing the lapping device in the self-locking chuck, insert it (not the working part) as far as possible, trying to press it to the upper point of the shaft to ensure alignment.
Hold the lapper and start the engine. Due to centrifugal forces, the lapping machine is locked in place by grips. After it is locked, release it.
Make 10 - 15 presses for 1-2 sec. of lapping on the nozzle valve.
After processing the valve, turn off the machine, holding the lapping by hand, to avoid dropping it on the valve seat.
WARNING: A longer pressure than 1-2 sec. will result in a deterioration of the valve seat machining quality.
WARNING: Too liquid a paste can spread out during operation and fall on different parts of the machine (screw mechanism, struts, sliding table, etc.). It is necessary to switch off the machine, clean its parts and bring the paste consistency to the level described in this manual, after which you can continue working.
Features of the nozzle valve seat treatment:
Do not "tear" the lapping from the valve too much during the machining. Make sure that the paste column is not torn, so that the paste is constantly agitated. When the lapping is raised, the average height of the lapping should not exceed 0.5 - 1 mm.
The force of pressure must be such that the vibrations of the lapping (machine shaft) can be clearly felt when it is pressed. Excessive force should not be applied, because it leads to instant "squeezing" of the paste from the contact spot and friction is almost dry, without paste.
Note: When working with a collet chuck, the procedure is the same except for the method of clamping the lapping in the collet. To clamp in the collet chuck, unscrew the collet nut and insert the inside of the lintel until it stops. After that, tighten the collet nut using the special wrench included in the delivery set.
WARNING: With one lapping you can treat the valve until the quality of the treatment pattern is clearly lost (individual spots, stripes and streaks appear). In this case, the lapping must be replaced with a new one.
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