Hyundai — Main pump disassembly
Repair & overhaul
From a Hyundai service manual — check it applies to your exact model before use.
Before you start
- Take care not to damage sliding surfaces of cylinder, spherical bushing, shoes, swash plate, etc.
- Do not remove needle bearing except when it is out of life span.
- Do not loosen hexagon nuts of valve block and swash plate support. If loosened, flow setting will be changed.
Procedure
- Select clean place. Spread rubber sheet or cloth on workbench.
- Remove dust, rust from pump surfaces with cleaning oil.
- Remove drain port plug(468) and let oil out of pump casing.
- Place pump horizontally with regulator-fitting surface down and separate pump casing(271) from valve block(312).
- Loosen hexagon socket head bolts(401) tightening swash plate support(251), pump casing(271) and valve block(312).
- Remove hexagon socket head bolts(412,413) and remove regulator.
- Pull cylinder block(141) out of pump casing(271) straightly over drive shaft(111).
- Pull out pistons(151), set plate(153), spherical bush(156) and cylinder springs(157) simultaneously.
- Remove hexagon socket head bolts(406) and then seal cover(F,261).
- Remove hexagon socket head bolts(408) and then seal cover(R,262).
- Tapping lightly fitting flange section of swash plate support(251) on pump casing side.
- Remove shoe plate(211) and swash plate(212) from pump casing(271).
- Tapping lightly shaft ends of drive shafts(111,113) with plastic hammer, take out drive shafts.
- Remove valve plates(313,314) from valve block(312).
- If necessary, remove stopper(L,534), stopper(S,535), servo piston(532), tilting pin(531), needle bearing(124) and splined coupling(114).
Tools required
- Allen wrench Amazon
- Double ring spanner Amazon
- socket wrench Amazon
- open end spanner Amazon
- adjustable angle wrench Amazon
- screw driver Amazon
- hammer Amazon
- pliers Amazon
- steel bar Amazon
- torque wrench Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Tighten bolts to specified torques on page 8-11, 12
- Replace seal parts such as O-rings and oil seals
Source: Hyundai service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.