3.14.2. Fuel pump


Fig. 3-79. Fuel pump: 1 – delivery branch pipe; 2 – filter; 3 – case; 4 – the soaking-up branch pipe; 5 – cover; 6 – the soaking-up valve; 7 – draft; 8 – lever of manual pumping; 9 – spring;
10 – clown; 11 – balance weight; 12 – lever of mechanical pumping; 13 – lower cover; 14 – internal remote laying; 15 – external remote laying; 16 – delivery valve

The device of the fuel pump is shown in fig. 3-79.
Check of the pump
Insufficient filling of the carburetor gasoline can depend on malfunction of the fuel pump, and also on a contamination or damage of pipelines.
To find a cause of defect, disconnect a hose from a delivery branch pipe 1 and by means of the lever 8 of manual pumping of fuel check whether fuel moves. If there is no fuel, then disconnect a hose from the soaking-up branch pipe 4 and check whether depression at the exit of this branch pipe is created. If depression is available, then, apparently, the pipeline is damaged and if is not present — that the pump is faulty.
In addition fuel pump can be checked at the stand. Rotating the drive roller having eccentricity of a cam of 1,25±0,02 mm with a frequency of 2000±40 min.-1, check giving of the pump (there have to be not less than 54 l/h at 20±5 °C) and pressure of forcing which has to be 23–30 kPa (2,3–3,0 m of a water column) at zero giving. At suspicion on malfunction disassemble the pump and check its details.
Dismantling, cleaning and check of details
For dismantling of the pump turn off a bolt of fastening of a cover 5, remove a cover and the filter 2. Then unscrew screws of fastening of the case to the lower cover, separate them, take out knot of diaphragms and a spring.
Wash out gasoline all details and blow compressed air.
Check integrity of springs of the pump.
Check whether there is no jamming of valves. Check diaphragms. On them there should not be cracks or hardening.
After check replace all worn-out or damaged details new. Replace the damaged laying of the pump new and before installation grease with a thin layer of lubricant.
Installation of the pump on the engine
For the correct installation of the fuel pump use two of three below-specified laying: And 0,27-0,33 mm thick; In thickness of 0,70-0,80 mm; With thickness of 1,10-1,30 mm.

Fig. 3-80. Scheme of control and adjustment of a vystupaniye of a pusher of the drive of the pump: And — laying 0,27-0,33 mm thick; In — laying 0,70-0,80 mm thick; d — a pusher vystupaniye

The scheme of installation of the pump is shown in fig. 3-80. You make installation in the following order.
Install a heat-insulating pro-rate on the block of cylinders, having put between them laying And, and on the plane which is interfaced to the pump, place laying of Century. Adaptation 67.7834.9506 measure d distance (the minimum size at which the pusher acts, established by slow turn of a bent shaft). If the size d is in limits of 0,8-1,3 mm, then fix the pump on the engine if d is less than 0,8 mm, In replace laying with laying And; if d is more than 1,3 mm, then In replace laying with laying of Page. Double-check the size d and fix the pump on the engine. Between the block of cylinders and a heat-insulating pro-rate always there has to be a laying And.