1999 HONDA CIVIC piston ring

Pressure Control
Low assist at higher speeds:
WhensteeringresistanceIsIow,suchaswhendrivingathighspeeds,orwhendrivingstraightahead,theinputshaftis
near or in the neutral position, so there is little or no fiow ro any of the power cylinder orifices. Most oI the feed pressure
fromthepumpisbypassedtothereservoir.Becauseofthis,thepressurestaysthesameinbothsidesofthepowercy||n-
der, resulting in low or no asslst
VALVE From PUMP
SECTION A-A
RETURN PASSAGElTo RESERVOIRI
POWER CYLINDER
STEERING GEARBOX
High assist at lower speeds:
When steering resistance is high. such as when driving at low speeds' or when turning the wheel wirh the vehicle
stopped,thedifference|nang|ecreatedbetweentheinputshaftandtheVa|veopensthef|uidpassageononeside,and
c|osesthefluidpassageontheotherside,ateachpairoforifices'Thef|uidpressureincreasesinthesideo|thepower
cy|inder|edbythe|argerf|uidpassage'Thisincreasedpressurepushesontherackpiston,a|lowingthesteeringwhee|to
be turned with light effort. on the other side of the power cylinder, the return passage opens allowing the steering tluid to
returnthroUghtheinputshafttothereservoir'Thef|uidpassagestothepowercy|inderautomatica||ychangeins|ze,
increasing as the steering resrstance increases. In other words, the passages become larger and power assist increases
when the steering effort would normally be high, (for example' when parking or making low speed turns)' and the pas-
sagesbecomesma||erandpowerassistdecreaseswhenthesteeringeffortwou|dnorma||ybe|ow,(forexamp|e,when
driving at high speeds or straight ahead).
FLUIO PASSAGE TO
POWER CYLINDER
/t=\\a!-4,))
=YjJ
RESERVOIR
SECTION A-A
l'
{High fluid Pressure}

Steering Gearbox
Disassembly (cont'dl
22. Carelully pry the piston seal ring and O-ring off theprslon rack.
CAUTION| Be caletul not to damage the inside ofseal ring groove and piston edges when removing
the seal rin9,
Replace.
17-52
Valve Body Unii Disassembly
23. Eefore removing the valve housing, apply vinyl tapeto splines of the pinion shaft.
24. Separate the valve housing from the pinion shaft/
valve using a press.
VALVE HOUSING
Vinylt.pe
PINION SHAFT
Check the inner wall of the valve housing where theseal ring slides with your finger. lf there is a step inthe wall, the valve housing is worn. Replace thevalve housing.
NOTE:
There may be the sliding marks from the sealring on the wall of the valve housing. Replace
the valve housing only if the wall is stepped.When the valve housing is replaced, jnstall new
shim(s) on the bearing surface of the housing toadjust the thickness.
Check the inside of valve housingwhether the wall is stepped.

Steering Gearbox
Reassembly (cont'd)
Valve Body Unit Reassembly
1. Apply vinyl tape to the stepped portion of the pin-
ion shaft, and coat the surface of the vinyl taoe with
the power steering fluid.
2. Install the backup ring ('96 -'97 models) or wavewasher ('98 -'00 models) with its tapered side as
shown below.
3. Coat the inside surface of the new valve oil sealwith power steering fluid.
4. Slide the valve oil seal over the pinion shaft, being
careful not to damage the sealing lip.
Vinyl t.po{Stepped ponion}
Tap6red position.
BACKUPGroove side.
sure the spring isseatod in the oil seal.
'98 - '00 mod.b:
CAUTION: InstEll ihe valve oil seal whh its groov.d
3ide tacing opposite tho boaring.
Apply vinyl tape to the splines and stepped portion
of the shaft, and coat the surface of the vinyl tapewith the power steering fluid.
Fit the new O-ring in the groove of the pinion shaft.Then slide the new valve seal ring over the shaft
and the groove in on the pinion shaft.
Remove the vinyl tape from the pinion shaft,
'96 - '97 models:
lip
7.
VALVE SEAL RIiIGReplace.Do not over-expand.
17-56
8. Apply power steering fluid to the surface of the
valve seal ring that was installed on the pinion
shaft.
9. Apply power steering fluid to the inside of the spe-cial tool. Set the larger diameter end of the specialtool over the valve seal ring.
10. Move the special tool up and down several times tomake the valve seal ring fit in the pinion shaft.11, Remove the soecial tool.
12. Turn the special tool over, and set the smaller diam-eter end of the special tool over the valve seal ring.Move the special tool up and down several times tomake the valve seal ring fit snugly in the pinion
shaft.
PISTON SEAL BINGSIZING TOOL07NAG - SR:togoAol07NAG - SR3|X)00
(g(m
Use the larger diameterend of the specialtool first to makethe valve seal ringfit in the pinionshaft.
Make the valve seal ringfit snugly in the pinionshaft using the other end(smaller diameter end) ofthe specialtool.

)
Steering Rack Reassembly
25. Coat the piston seal ring guide with power steering
fluid, then slide it onto the rack, big end first'
26. Position the new O-ring and new piston seal rlng on
the special tool, then slide them down toward the
big end of the tool
NOTE:
. Do not over expand the resin seal rings lnstali
the resin ;eal rings with care so as not to dam-
age them. After installation, be sure to contract
the seal ring using the specialtool (sizing tool)
. Replace the piston's O-ring and seal ring as a set'
27. Pull the O-ring off into the piston groove, then pull
the piston seal ring off into the piston groove on top
ol the O-ring
PISTON SEAL RINGGUIDE07GAG - SD4O10A ol
07GAG - SD,ol(xt
Coat the piston seal ring and the inside of the spe-
cial toolwith power steering fluid.
Carefully slide the tool onto the rack and over the
piston seal ring.
Move the special tool back and forth several times
to make the piston seal ring fit snugly in the piston'
PISTONReplace.
E
PISTON
31. Wrap vinyl tape around the rack teeth and rack end
edges, then coat the surface of the tape with the
power steering fluid
NOTE: Make sure that the vinyl tape is wrapped
carefully so that there is no stepped portion
Coat the inside surface of the new cylinder end seal
with power steering fluid.
Install the cylinder end seal onto the steering rack
with its grooved side toward the piston.
CAUTION: When installing the cylinder end seal,
be caieful not damage the sealing lip face of tho
seal with the edgss or teeth of th€ ste€ring rack'
CYLINDER END SEAL
Make sure thesPring is in the cylinder
end soal
Remove the vinyl tape from the steering rack
NOTE: Remove any residue oftape adhesive(cont'dl
17-59

Steering Gearbox
Reassembly {cont'd)
35. Install the new backup ring on the steering rack,then place the cylinder end seal to piston.
Grease the steering rack teeth, then Insen the steer-ing .ack into the gear housing.
CAUTION: Be careful not to damage to inner sur-face of the cylindsr housing with the rack edges.
36.
BACKUP RING
17-60
37. Install the flange bolt into the end of the steerinorack until it bottoms in the hole, then back thlflange bolt out 1/4 turn. Hold the flange bolt andtighten the flange nut against the rack by hand.
38. Install the cylinder end seal into the bottom of thecylinder by pressing on the bolt with a press asshown.
CAUTION: Do not push on the boh with excessiveforce as it may damage tho cylinder end seal.
12 x 175 mm FLANGE BOLT{P/N 90177 - SLo - 000}
12 mm FLANGE NUT
?qRemove the flange bolt. and center the steeringrack.
Wrap vinyl tape around the rack end edges. andcoat the surface of the tape with the power steeringfluid.
NOTE: Make sure that the vinyl tape rs wrappedcarefully so that there is no stepped portion.
Preas

)
41.Coat the inside surface of the new cylinder end seal
with power steering fluid.
Install the cylinder end seal onto the steering rack
with its grooved side toward the piston'
Push in the cylinder end seal with your finger'
CAUTION: When installing the cylinder end sesl'
be carelul not damage the sealing face ot the seal
with the threads and burrs at the staked position oI
the cylinder housing.
trCYLINDES END SEAL
Replace.Make sure the sPring
is in the cylincler end seal
CYLINDER END
SEAL
Remove the vinyl tape from the steering rack'
NOTE: Remove any residue oftape adhesive
Hold the steering gearbox using a C-clamp as shown'
GEARBOX
C-CLAMP:
l-,
46.
47.
Coat the inside surface of the cylinder end with
power steering fluid, then installthe cylinder end by
screwing it into the cylinder housang.
Remove the C-clamp from the steering gearbox'
After tightening the cylinder end' stake the point of
the cylinder housing shown below For'98 -'00
models go to step 51.
NOTE: Stake the cylinder in the position opposite
from where the stake was removed during disas-
semoly.
Be careful not to damage
the bushing when inserting
the cylinder end.
49. Select the 32 mm shim(s) ('96 -'97 model only)'
NOTE: Only reinstall the original 32 mm shim(s)
when the steering gearbox is reassembled without
replacing the pinion shatt, valve housing, and gear
box housing with new ones.
lf the pinion shaft, valve housing, and gearbox
housing are replaced, select the new shim{s) as fol-
lows.
Shim selection:
a. Set the four 32 mm shims on the bearing surface of
the gearbox housing. Total thickness of the four
shims should equal no more than 0 70 mm'
Shim set: four 32 mm shims (Thickness: 010 mm'
0.15 mm, 0.20 mm, 0.25 mm respectivelyl
CAUTION: Th€ four 32 mm shims do not have
thickness identification marks Measure the thick-
ness of each shim using a micrometsr, and mark
the shim lor identification.
(cont'd)
17-61
Stake point. Depth: 1 0 mm (0.04 in)

Front Brake Caliper
It
Disassembly
NOTE: There are two types of front brake calipers:
The caliper types can be identified by the "5410" or"2056" stamped on the caliper body as shown below.
Check the type of the brake caliper before servicing.
5410 Type:
NOTE: For 2056 type disassembly procedures, see page
19-14.
@o Never use an air hose ot dry brush to clean brakg
assemblies.
. Use an OSHA approved vacuum clganer to avoid
breathing brake dust.
CAUTION:
. Do not spill brake lluid on the vehicls; it may damage
the paint; if brake fluid does conlact the paint, wash
it off immedistely with waier.
. To prevenl spills, covet the hose ioin$ with rags or
shop towels.
. Clean all parts in brake fluid and air dry; blow out all
passages with compressed air.
L Remove the banjo bolt, and disconnect the brake
hose from the caliDer.
CALIPER
BANJO EOLT
SEALINGReplace.BOLTS
Remove the caliper bolts, then remove the caliper
from the bracket.
lJReplace.
3. Remove the caliper pins and pin boots from the
calioer bracket,
CALTPER PIN B CAL|PER BRACKET
CALIPER PIN A
4, lf necessary. apply compressed air to the caliper
fluid inlet to get the piston out. Place a shop rag or
wooden block as shown to cushion the piston when
it is expelled. Use low pressure air in short spurts.
@. Do not place your iingers in tront ol the piston.
. Do not use high air pressure; use 8n OSHA
approved 30 PSI nozzls,
Remove the piston from the caliper, and check the
piston for scoring.
Remove the boot clip, piston boot and piston seal.
CAUTION: Take care not to damage the cylindcr
PISTON SEALReplace.
BOOT CLIPReplace.
\,
,t. (
)PISTON BOOT
CALIPER BODYCheck for scoring
(cont'd)
19-13

Front Brake Caliper
2056 Type:
@
Disassembly (cont'dl
Nevor u3e an air hos€ or dry brush to clgan brake
assomblios.
Use an OSHA approved vacuum cl6aner to avoid
braathing braks duet.
CAUTION:
. Do not spill brakefluid on ths vchicle; it may damage
the paint; if brako fluid does contact the p.int. wash
it olt immediately with wato..
. To prevsnt spills, cover the ho3o ioints whh rag3 or
shop towels.
. Cl€an all parts in brake fluid and air dry; blow out 8ll
passagss with compr63€d air.
1. Remove the banjo bolt, and disconnect the brake
hose from the caliper.
SEALING WASHERS
Remove caliper bolt B, pivot the caliper up out of
the way, then remove the caliper from the bracket.
Remove the guide pin boot from sleeve A on the
caliDer bracket.
GUIDE PIN BOOTReplace.
GALIPER BRACKETCheck tor cracks.
Check for damage.
19-14
4. Remove the pin boot, sleeve B and sleeve boot
from the caliper body.
CALIPER EODYCheck for scoringon cytinder wa .
SLEEV€ BCheck for damage.
lf necessary, apply compressed air to the csliper
fluid inlet to get the piston out. Place a shop rag or
wooden block as shown to cushion the oiston when
it is expelled. Use low pressure air in short spurts,
a
a
Do not placo your lingers in ftont ol tho pkton.
Do noi usa high air prsssure; uso an OSHA
approved 30 PSI nozzle.
Remove the piston from the caliper, and check thepiston for scoring.
WOODEN ALOCK