Chevrolet 10 Series 1970 Service Manual page 526

STEERING 9-18
F ig . 2 7 —C h e c k in g B elt Tens ion w ith
HYDRAULIC SYSTEM CHECKS
The follow in g proced u re outlines methods to identify
and isolate pow er s tee rin g hydraulic c ircu it d ifficu lties.
T h is test is divided into two parts.
p ro v id e s means o f determ inin g whether pow er steerin g
system hudraulic parts are actually faulty.
b e r one results in readings indicating faulty hydraulic
op eration , test number two w ill identify the faulty part.
B e fo r e p e rfo rm in g hydraulic c ircu it test, c a re fu lly check
b elt tension and condition o f d rivin g pulley.
Test N um ber O n e —O il Circuit Open
Engine must be at norm al operating tem peratu re.
fla te fron t tir e s to c o r r e c t p ressu re.
F ig . 2 8 — O il Pressure G au ge J — 5176 In s ta lle d
Tool J — 7316 (T y p ic a l)
T e s t number one
If test num­
In­
A ll tests are made
F ig . 2 9 —C h e c k in g F lu id Tem perature
with engine idling, so adjust engine id le speed to c o rre c t
sp ecifica tio n s lis te d in Section 6 and p roceed as fo llo w s:
a. With engine not running, disconnect fle x ib le p re s ­
sure line fro m pump and in stall T o o l J-5176 as
shown in F igu re 28.
off va lve and pump.
b. R em ove f ill e r cap fro m pump r e s e r v o ir and check
fluid le v e l. F ill pump r e s e r v o ir to fu ll m ark on
dip stick. Start engine and, holding steerin g wheel
against stop, check connections at T o o l J-5176 fo r
leakage. B leed system as outlined under M ainte­
nance and Adjustm ents.
(T o o l J-5421) in r e s e r v o ir f i l l e r opening (fig. 29).
M ove steerin g wheel fro m stop to stop se v e ra l
tim es until th erm om eter indicates that hydraulic
fluid in r e s e r v o ir has reached tem peratu re of
150° to 170°.
CAUTIO N: To preven t scrubbing fla t spots on
t ir e s , do not turn s te erin g wheel m ore than fiv e
tim es without ro llin g veh icle to change t ir e - t o -
flo o r contact area.
c. Hold steerin g wheel against a stop m om en tarily
and read p ressu re gauge.
sure is below sp ecification s, a faulty hydraulic
circu it is indicated.
faulty, p roceed with test number two.
Test N um ber T w o —O il Circuit Closed
a. Slowly turn shut-off va lve on J-5176 to closed
position and read p ressu re indicated on gauge.
Quickly reopen va lve to avoid pump dam age. If
indicated p ressu re
pump output is below requirem en t and pump may
be considered faulty.
within sp ecification s, it may be s a fe ly assumed
that the external hoses, connections o r steerin g
g ea r is at fault.
Gauge must be between shut-
Shut-off valve must be open.
In sert th erm om eter
If the maximum p r e s ­
T o determ in e which p art is
is le s s than sp ecification ,
If p ressu re indicated is
CHEVROLET TRUCK SERVICE MANUAL