1969 corvette wiper problems need help please
Thread Starter
8th Gear
Joined: Aug 2015
Posts: 8
Likes: 0
1969 corvette wiper problems need help please
hi im restoring 69,switched over to electric headlight kit,did away with wiper door use the longer hood,got everything electrical working but these wipers got me stumped,frame off restored all new wire harness all gauges lights all good,new wiper motor and relay when i cut wipers on nothing relay clicks.i was checking all my grounds and made shure switch grounded,gave the wiper motor nudge started working checked all speeds worked cut them off they parked buy cut back on dead,will only start if push wiper arm,with doing away with wiper door i got override switch under dash jumped out and the door switch under hood ,i have a diagram of wiring and bench tested motor i sent willcox corvette email he did not seem to have time and said for me to join here some good info,i would realy take any ideas on what to look for got me stumped ,cant figure out if i missing something what kicks motor out of park to start?oh one other thing when i cut switch on wipers when relay clicks the dash turn signals both light up just for a second when relay clicks on thanks please help darryl
Drifting
Joined: Apr 2010
Posts: 1,857
Likes: 332
From: Cartersville GA
Willcox has some videos on wiper motor and wiring....I would start their. The link below is there Youtube channel.
https://www.youtube.com/channel/UC7s...nAZS1_McOMezjQ
Brian
https://www.youtube.com/channel/UC7s...nAZS1_McOMezjQ
Brian
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Thread Starter
8th Gear
Joined: Aug 2015
Posts: 8
Likes: 0
wiper motor want kick out of park
yes motor worked all speeds and parked when removed blue wire from ground but in car will not come out of park when push switch over untill you give wiper arm a slight push then runs all speed when cut off it parks but will not kick in untill push it again,cant figure out what im missing what makes motor kick out of park when push switch over?
Thread Starter
8th Gear
Joined: Aug 2015
Posts: 8
Likes: 0
wiperhelp
yes motor worked all speeds and parked when removed blue wire from ground but in car will not come out of park when push switch over untill you give wiper arm a slight push then runs all speed when cut off it parks but will not kick in untill push it again,cant figure out what im missing what makes motor kick out of park when push switch over?
Thread Starter
8th Gear
Joined: Aug 2015
Posts: 8
Likes: 0
one other thing mine has long hood did away with wiper door did away with override switch under column and switch under hood hooked wires together dont see why want work got my 12 volts on red wire and yellow wire center lug on motor so why when i ground blue wire why want run like on bench?
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Okay... So I have this right...
You bench test the motor(s) and it works fine. You put the motor in the car and wire it up and it fails to start unless you give the wiper arms a nudge... Then it works fine with both speeds and parks.... Is this correct?
You have the limit switch by-passed and you do have 12 volts going to the red wire (the one coming out of the can). Is this correct?
Have you tried running a test ground to the motor? It's possible that you have a bad or corroded ground wire issue and running a test jumper from the motor to your engine would answer that question quickly.
If the test ground didn't change anything... then I'd remove it and then run a hot wire to the center terminal and simulate the bench test only in the car.... The linkage may be binding up the motor (unlikely but possible).
If nothing changes then I would possibly take a look at the wiper relay inside the car. Since the first start up of the motor is low speed (both wires grounded), you may have a grounding issue there. If you have to go to the relay, pop off the relay cap and run some fine sand paper through the contacts and try the motor again.
Willcox
You bench test the motor(s) and it works fine. You put the motor in the car and wire it up and it fails to start unless you give the wiper arms a nudge... Then it works fine with both speeds and parks.... Is this correct?
You have the limit switch by-passed and you do have 12 volts going to the red wire (the one coming out of the can). Is this correct?
Have you tried running a test ground to the motor? It's possible that you have a bad or corroded ground wire issue and running a test jumper from the motor to your engine would answer that question quickly.
If the test ground didn't change anything... then I'd remove it and then run a hot wire to the center terminal and simulate the bench test only in the car.... The linkage may be binding up the motor (unlikely but possible).
If nothing changes then I would possibly take a look at the wiper relay inside the car. Since the first start up of the motor is low speed (both wires grounded), you may have a grounding issue there. If you have to go to the relay, pop off the relay cap and run some fine sand paper through the contacts and try the motor again.
Willcox
Last edited by Willcox Corvette; Sep 15, 2015 at 11:27 AM.
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Drifting
Joined: Jul 2015
Posts: 1,765
Likes: 254
From: Catlett VA
wipers
one other thing mine has long hood did away with wiper door did away with override switch under column and switch under hood hooked wires together dont see why want work got my 12 volts on red wire and yellow wire center lug on motor so why when i ground blue wire why want run like on bench?
1968 Corvette Wiper System
Wiper door Operation
Vacuum Reserve Tanks & Check Valve- The tanks areused to store vacuum and is located under the left fender near the cowl. The check valve is used to allow vacuum intothe intake manifold. The check valve islocated in vacuum harness near the center of the cowl. Both these items are also part of theheadlamp vacuum system.
Vacuum Control Solenoid- The control solenoid iselectrically actuated but is used to control vacuum at the Vacuum Relay ValveDiaphragm. The solenoid is mounted onthe tachometer housing under the dash.
Vacuum Relay Valve- The Relay Valve routes vacuum toproper side of the door actuator for opening or closing cycle. The valve is located under rear of rightfront fender. This valve is operated byvacuum on a spring loaded diaphragm.
Manual Valve- The manual valve in series with thesolenoid is used to open the door for service procedures. This switch should also be used to keep thedoor open when frequent but intermittent wiper use is desirable. The manual valve is located next to thesteering column.
Wiper Door Actuator- The actuator converts vacuuminto the mechanical force (through a push rod attached to a piston within theactuator) needed to open the wiper door. The actuator is mounted on the upper right portion of the cowl.
WIPER MOTOROPERATION
The electrical portion of the wiper system is composed ofthe following components.
Wiper Motor and Dash Switch- The wiper motor used inthis system is a 2 speed “Type C Depressed Park” motor (See Fig. 8). It is mounted in the conventional manner onthe firewall. The dash switch is a bladetype mounted in the upper portion of the center instrument cluster.
Limit Switch- The limit switch has “normally open”contacts and is used to prevent wiper motor operation until the lid reaches thefull open position. The lid, when itreaches full open position, activates the switch contacts to a closed positioncompleting the motor armature circuit to ground via the service switch. The limit switch is located in the rightportion of the plenum area.
Vacuum Control Solenoid-Although this solenoid wasmentioned under the vacuum components it is also a part of the electricalcomponents. The control solenoid indeactivated position allows vacuum to the relay valve diaphragm, which in turnkeeps the wiper door shut. The solenoidwhen actuated cuts off vacuum to the relay valve diaphragm, which in turn opensthe wiper door. The wiper switchcontrols current to the solenoid.
External Relay- The external relay has two functions
1) With the ignition switch and the wiper dash switch “On”, it completes thewiper motor shunt field circuit to the dash switch and (2) it provides aby-pass circuit around the motor “Hi” speed resistor if the wiper dash switch isleft in the “Hi” position when the ignition switch is turned off. The reason for the by-pass circuit is asfollows:If the there wasno by-pass circuit and if the wiper dash switch was left in the “Hi” speedposition when the ignition switch was turned off, the wiper motor would run in“Hi” speed while trying to park the blades. This would cause the wiper motor to recycle (blades would move in andout of the parking area rapidly and the wiper would not shut off). The by-pass circuit, however, causes thewiper motor to operate in “Lo” speed so that the wiper motor will park theblades and shut off correctly. Thisrelay is mounted under the front of the floor console and is accessible afterremoving the trim pad on the right side of the cluster assembly.
Override Switch- A manually operated override switch(located next to the steering column under the dash) is connected in serieswith the limit switch and may be used to stop the blades on the windshield in aconvenient position for service operations. Except when the operations require the use of the switch, it shouldalways be left in the “Off” position (fully turned to the right). When the switch is left “On” even with theignition switch OFF there is a low but constant drain on the battery.
Theelectrical portion of the system operates as follows (reference Fig. * and 9):
Wiper Switch OFF- Turning the ignition switch Oncompletes the battery positive (B+) circuit via wiper terminal No. 2 to oneside of both the gear box and external relay coils. Note also that B+ is connected direct towiper motor gear box relay switch via wiper terminal No. 8.
Lo Speed Circuit- Moving the dash switch to the “lo”speed position accomplishes three (3) functions simultaneously:
- Thewiper gearbox relay coil circuit is completed to ground at the dash via wiperterminal No. 1. With the coil energized,the relay switch contacts close completing the B+ circuit to (1) the motorwindings and (2) via terminal No. 7 to the vacuum control solenoid.
- Withthe control solenoid energized vacuum to the relay valve diaphragm is stopped,thus the wiper door starts to open.
- Thewiper external relay coil circuit is also completed to ground at the dashswitch via wiper terminal No. 1. Withthis coil energized, the relay switch completes the wiper motor shunt fieldcircuit from wiper terminal No. 3 to the dash switch. The dash switch completes the circuit toground.
The motor armature circuit iscompleted to ground via terminal No. 6 when the lid has opened far enough totrip the limit switch. With the armaturecircuit completed, the wiper motor will start to run.
Hi Speed Circuit- Moving the dash switch to the “Hi”speed position opens the shunt field circuit to ground at the das switch. The shunt field current then flows throughthe 20-OHM resistor located on the wiper motor terminal board to ground.
NOTE: When the dash switch is in the “Lo” speed position,the shunt field current flows direct to ground at the dash switch bypassing theresistor.
Parking Circuit- When the owner first turns thewipers “Off” at the dash switch, two simultaneous functions occur:
- Theexternal relay coil circuit is opened to ground and the relay switch contactschange position to complete the motor shunt field circuit to ground at therelay switch. With the shunt fieldconnected direct to ground, the wiper motor runs in “Lo” speed during the parkcycle.
- Themotor gearbox relay coil circuit is opened to ground at the dash switch. However, at this stage of operation, thegearbox relay switch contacts remain closed maintaining B+ to the wiper motorwindings and the vacuum control solenoid. With these circuits still complete, the wiper motor continues to run andthe control solenoid stays energized, the lid stays in the open position, whichin turn keeps the limits switch tripped.
Note: Keep in mind that thelimit switch completes the motor armature circuit to ground when activated bylid.
Wiper Off- The wiper motorgearbox mechanism is programmed so that when the blades reach the parkposition, the gear mechanism opens the gearbox relay switch contacts. This shuts off the wiper motor and opens B+circuit to the vacuum control solenoid, which allows the lid to close.
Thread Starter
8th Gear
Joined: Aug 2015
Posts: 8
Likes: 0
thanks so much for reply after 2 weeks of working on it i found my problem,i have run grounds from battery checked all wires bench tested motor,my brand new motor is bad,if i gave it slight nudge it ran but would not kick in from a start,put my old motor on worked fine,seems not as fast as new one but both speeds work and it starts thats main thing,crazy run great on bench test but not car?i have read somewhere that on the wiper over ride switch under dash if left on will drain battery? got man wired direct since did away with wiper door,use long style hood guess i could install some kind of switch under dash to cut of 12 volts when not use wipers?when i install wiper arms do i put them on in park position seen pictures manual where driver side at bottom hits stop pass side just tuches top driver arm?any info on align wipers would help thanks for all help feel like wait lifted off me wiper motor was driving me crazy