Before commencing to dismantle the pump, thoroughly clean the exterior and make a file mark across the two flanges of the pump housing, as a guide when re-assembling.
Remove the six securing screws and separate the two halves of the main casting.
Turn the diaphragm, and pull rod assembly through an angle of 90°, when it may be disconnected from its securing slot in the connecting link and withdrawn. Remove diaphragm spring.
Withdraw the valve retainer screws from inside the upper casting and remove the retainer plate, valve assemblies, and valve retainer gasket.
On latest type pumps, valve retaining plates are omitted, the valve assemblies being a light tap fit into the casting.
All pump parts must be thoroughly cleaned in order to ascertain their condition. Wash valves, upper castings, filters and other parts which come into contact with the fuel in a clean paraffin bath separate from that used for dirtier components.
Upper and lower pump castings should be examined for cracks or damage. AC Repair Kits contain the items normally needed for fuel pump 'first aid' repair and all of these should be used on each job, the corresponding worn parts being discarded.
Replace valve retainer gasket, valves, valve retainer, and secure in position with two retaining screws, or tap new valves into recesses on latest pump types.
Replace filter gauze and cork seating gasket in position. Refit filter bowl.
Place the diaphragm spring in position in the pump body. Place the diaphragm assembly over the spring (the pump rod being downwards) and centre the upper end of the spring in the lower protector washer. When fitting the diaphragm assembly the small locating tabs should be at position 'A' shown in the illustration. The diaphragm assembly should then be pushed down until the flattened end of the pull rod enters the slot in the link and then turned a quarter turn to the left until the diaphragm locating tabs are at
position 'B' and then they will be in line with the locating mark cast on pump body. The sub-assemblies of the pump are now ready for fitting together, and this is carried out as follows:
Push the rocker arm towards the pump until the diaphragm is level with the body flanges.
Place the upper half of the pump into the proper position, as shown by the mark made on the flanges before dismantling. Install the cover screws and spring washers and tighten until the heads of the screws just engage the washers.
Before finally tightening the cover screws, the rocker arm must be held at its inward position preferably using a short piece of tube as shown in the illustration. Sufficient pressure must be exerted to draw the diaphragm inwards until its edges no longer protrude beyond the pump flanges.
While the rocker arm is so held, the cover screws should be securely tightened, working from side to side so as to keep the pressure even.
UH - Standard type of pump for engines over 1,200 c.c. Detachable valve assemblies and visible side filter. Mounting stud holes arranged diagonally
FH - As UH but mounting holes side by side.
UH - Standard type of pump for without filter. Mounting stud holes arranged diagonally
FH - As UE but mounting holes side by side.
U - Standard type of pump with metal filter cover. Mounting stud holes arranged diagonally
UF - As U but mounting holes side by side.
UG - Standard type of pump with glass filter bowl on top. Mounting stud holes arranged diagonally
FG - As UG but mounting holes side by side.
T - Wearly type standard size with separate valves and pump. Mounting stud holes arranged diagonally
TF - As type T but glass filter bowl on top.
TF - As type T but mounting holes side by side.
Y - Small size pump for engines up to 1,200 c.c. Mounting stud holes side by side
YD - As type Y but later design detachable valve with assemblies.
YJ - As YD but no filter.
YE - Small size pump for Diesel fuel feed. Glass filter bowl, mounting holes side by side.
CG - Standard size pump, flat link filter bowl on top, mounting holes side by side.
VP - Standard size vertical diaphragm for Diesel fuel feed. Mounting stud holes side by side.
VPP - Vertical diaphragm / piston type for Diesel fuel feed.
|Assembly Part No.
Nut and Sleeve
|PARTICULARS OF UNION||Union Nut||Pipe Sleeve
|Part Number||Description||Thread into Pump||Thread for Union Nut|
|114795||114626||1/4" Straight, for pipe sleeve||1/8" x 27*||7/16" x 24||114527||114628|
|114796||114629||5/16" Straight, for pipe sleeve||1/8" x 27*||1/2" x 24||1524190||114631|
|114797||114633||5/16" Elbow, for pipe sleeve||1/8" x 27*||1/2" x 24||1524190||114631|
|114798||114632||1/4" Elbow, for pipe sleeve||1/8" x 27*||7/16" x 24||114627||114628|
|856810||5/16" Straight, for soldered nipple||1/8" x 27*||1/4" Gas||Uses Washer 851011|
|1524114||5/16" Straight, for soldered nipple||1/2" x 20||1/4" Gas||Uses Washer 855136|
|1524730||1/4" Straight, for pipe sleeve||1/2" x 20||7/16" x 24||114627||114628||Conical seat, in pump|
|1524729||5/16" Straight, for pipe sleeve||1/2" x 20||1/2" x 24||1524190||114631||Conical seat, in pump|
|1524328||1/4" Straight, for flared pipe||1/2" x 20||7/16" x 24||Uses Washer 855136|
|1524322||5/16" Banjo, for pipe sleeve||1/2" x 20||1/2" x 24||1524190||114631||
Also uses -
Washer 855136 (2)
|* N.P.T.F.||1524555||1/4" Banjo, for pipe sleeve||1/2" x 20||7/16" x 24||114627||114628||Ditto|