Fitment Centre Training Part 4

7/25/2019 Fitment Centre Training Part 4

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rouble Shooting Observations

Inspection of the CALIPERS

What TYPE of Caliper is it?

Are the SLIDE PINS in good

condition?

Does the PISTON move freely in the

Caliper?

Are there CRACKS on the piston or

the Casting?

Are the RETAINING BOLT HEADS

damaged?

Are the MOUNTING POINTS solid?

Light Duty Trouble

Shooting


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Trouble Shooting Observations

Inspection of the DUST SEALS

Slide Pin Seals

Pistons Seals

n Place?

Torn?

Cracked ?

Melted?

Light Duty Trouble

Shooting


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Problem Solving:

ObservationsHydraulic Hoses Leaking

Brake fade or Failure

Excessive Pedal Travel

Vibration or Scuffing

Incorrectly tightened

Cuts from foreign matter

Pipes cracked

Actions:Replace completely

Light Duty Trouble

Shooting


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Trouble ShootingObservations

Inspection of the DISCS Are the discs

VENTILATED or SOLID?

Are the Discs

CRACKED or GROOVED?

Are the Discs Blued

One Side or Both

Are there signs of METAL PICK-UP?

Are there HIGH SPOTS?

Is the Disc WARPED?

Is the Disc in specification for

THICKNESS?

Light Duty Trouble Shooting


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How to measure the disc for wear

The tools required to measurethe disc are the outside caliperand the ruler.

Close the caliper claws on thedisc by turn the adjusting nut take care not to over tightenthe caliper, twist the caliper

and pull it from the disc. Use the ruler to check the gap

between the caliper claws.

Ruler

Outside caliper

Claws

Adjusting nut


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How to check if the disc is warped

or damaged Check the wheel

bearing end float,

adjust to specifications

or replace the bearing.

Use the dial gauge to

check for any disc run-

out which indicates a

warped disc or badly

damaged disc


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Hydraulic systems

BRAKE FLUIDCheck the Brake Fluid

Clear (fluid in good condition)Black (dirty fluid)

Muddy Brown (overheated fluid)

When was the brake fluid last CHANGED?

Black

Muddy brown

Clear


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CATEGORY AAUDIBLE.

ComplaintSqueal - High-pitched noise.

Possible causesDust.

Dirty Pistons and Calipers.

Wheel Bearings worn or badly adjusted.

Discs worn.

Suspension Rubbers Perished.

90% from the rear after front fitment.

Squeal can be defined as a noise that has beenallowed to be transmitted from the source, intothe vehicle body where it is amplified to humanaudible levels.

CATEGORY AAUDIBLE.

ComplaintSqueal - High-pitched noise.

Possible causesDust.

Dirty Pistons and Calipers.

Wheel Bearings worn or badly adjusted.

Discs worn.

Suspension Rubbers Perished.

90% from the rear after front fitment.

Squeal can be defined as a noise that has beenallowed to be transmitted from the source, intothe vehicle body where it is amplified to humanaudible levels.

Light Duty Trouble ShootingLight Duty Trouble Shooting


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CATEGORY AAUDIBLE

ComplaintRattle - Metallic rattle,clunking

Possible causes

Pads not fitted correctly

Anti Rattle Plates Omitted

Anti Rattle Springs

Omitted

Bent

Inherent to Vehicle

CATEGORY AAUDIBLE

ComplaintRattle - Metallic rattle,clunking

Possible causes

Pads not fitted correctly

Anti Rattle Plates Omitted

Anti Rattle Springs

Omitted

Bent

Inherent to Vehicle



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CATEGORY AAUDIBLE

ComplaintGrinding - Heavy metal grinding, scraping noise

Possible causes

Disc Pads BACK TO FRONT

Friction material completely worn out

CATEGORY AAUDIBLE

ComplaintGrinding - Heavy metal grinding, scraping noise

Possible causes

Disc Pads BACK TO FRONT

Friction material completely worn out



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Category BPhysical.

ComplaintLock-up - Brakes grab & lock-up,

Possible cause

Air in Hydraulic System.

Foreign objects.

Wrong co-efficient of friction.

Load sensor valve not working or not

set-up.

Narrower Tyres fitted.

Suspension raised.

Category BPhysical.

ComplaintLock-up - Brakes grab & lock-up,

Possible cause

Air in Hydraulic System.

Foreign objects.

Wrong co-efficient of friction.

Load sensor valve not working or not

set-up.

Narrower Tyres fitted.

Suspension raised.



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Category BPhysical

Complaint

Judder - Rhythmic, oscillatingshudder, also noisy.

Possible causes

High spots on Discs

Caliper seizure

Slide Pins Bent

Discs Warped

Category BPhysical

Complaint

Judder - Rhythmic, oscillatingshudder, also noisy.

Possible causes

High spots on Discs

Caliper seizure

Slide Pins Bent

Discs Warped



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Category BPhysical.

Complaint

Snatching - Brakes grab& let go.

Possible causes

Caliper action not

smooth.

Brake fluid

contaminated.

Category BPhysical.

Complaint

Snatching - Brakes grab& let go.

Possible causes

Caliper action not

smooth.

Brake fluid

contaminated.



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Category C Performance.ComplaintFade - Spongy feel to pedal, resulting

in pedal fade.

Possible causes

Hydraulic Blockage.

Overloading.

High Speed driving and short

braking.

Modified vehicle.

Category C Performance.ComplaintFade - Spongy feel to pedal, resulting

in pedal fade.

Possible causes

Hydraulic Blockage.

Overloading.

High Speed driving and short

braking.

Modified vehicle.



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Category C Performance.Complaint

Brake Fade - Solid brake pedal, insufficientstopping power.

Possible causes

Contaminated Brake Fluid.

Sticking/Seized Calipers.

Category C Performance.Complaint

Brake Fade - Solid brake pedal, insufficientstopping power.

Possible causes

Contaminated Brake Fluid.

Sticking/Seized Calipers.



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CategoryC

Performance.

ComplaintDead Pedal - Dead non -

progressive feel to pedal.

Possible causes

Caliper Seized.

Master Cylinder Blocked.Brake Pipes Blocked.

Backing Plates Bent.

CategoryC

Performance.

ComplaintDead Pedal - Dead non -

progressive feel to pedal.

Possible causes

Caliper Seized.

Master Cylinder Blocked.Brake Pipes Blocked.

Backing Plates Bent.



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Light duty trouble shooting

Category DSubliminal

ComplaintHesitation a short delay before thebrakes take

Possible causes

Air in hydraulic system.

Insecure brake mountings.

Pedal free play excessive.


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Problem Solving:Observations

Foreign objects.

Chips and/or Gouges on the

friction material.

Discs Badly scoured.

Objects picked-up by tyres and

thrown into the caliper.

ACTION:Clean out caliper and replace brake

pads.


Foreign objects.

Chips and/or Gouges on the

friction material.

Discs Badly scoured.

Objects picked-up by tyres and

thrown into the caliper.

ACTION:Clean out caliper and replace brake

pads.



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Discs Warped.Pedal Jump.

Judder.

Steering Pull.

Poorly Skimmed.

Over Heated.

Actions:Replace the Discs and the pads

as well as the Brake Fluid.


Discs Warped.Pedal Jump.

Judder.

Steering Pull.

Poorly Skimmed.

Over Heated.

Actions:Replace the Discs and the pads

as well as the Brake Fluid.



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Slide Pins Bent /Worn.

Caliper Seizure.

Sticky Caliper Movement.

Judder or Squeal.

Steering Pull.

Not correctly tightened.

Forced at some stage.

Actions:Remove and replace the pins and seals.

Check for other damage.


Slide Pins Bent /Worn.

Caliper Seizure.

Sticky Caliper Movement.

Judder or Squeal.

Steering Pull.

Not correctly tightened.

Forced at some stage.

Actions:Remove and replace the pins and seals.

Check for other damage.



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One pad worn

High spots

Steering pull

Slide pins coated with old lubricant

& brake dust

Dust covers worn or melted

ACTIONSOverhaul Caliper.

Replace all Seals and Brake Fluid.

Lubricate slide pins with CV grease.


One pad worn

High spots

Steering pull

Slide pins coated with old lubricant

& brake dust

Dust covers worn or melted

ACTIONSOverhaul Caliper.

Replace all Seals and Brake Fluid.

Lubricate slide pins with CV grease.



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Problem Solving:

Observation Disc pads back to frontGraunching

Grinding

Lack of Knowledge

Action:Training required

Replace pads and fit correctly

Problem Solving:

Observation Disc pads back to frontGraunching

Grinding

Lack of Knowledge

Action:Training required

Replace pads and fit correctly



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Pistons SeizedHigh pad wear rate

Disc warp

Disc discoloration

Brake fade

Calipers never cleaned or

overhauled

Dust covers torn, melted or

missing

Poor maintenance

Actions: Overhaul CalipersReplace the seals andthe brake fluid


Pistons SeizedHigh pad wear rate

Disc warp

Disc discoloration

Brake fade

Calipers never cleaned or

overhauled

Dust covers torn, melted or

missing

Poor maintenance

Actions: Overhaul CalipersReplace the seals andthe brake fluid



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Problem Solving: Observationsand Consequences

Dust Covers TornPiston seizure

Brake fluid leak

Caliper action not smooth

Brake fluid contaminated

Dust covers aged and

perished

Poor fitting proceduresForeign objects

Actions:Remove and replace

Problem Solving: Observationsand Consequences

Dust Covers TornPiston seizure

Brake fluid leak

Caliper action not smooth

Brake fluid contaminated

Dust covers aged and

perished

Poor fitting proceduresForeign objects

Actions:Remove and replace



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Problem Solving:

ObservationsHydraulic Hoses LeakingBrake fade or Failure






Problem Solving:

ObservationsHydraulic Hoses LeakingBrake fade or Failure








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Problem Solving:

ObservationsMetal Pick-up

Discs badly scored

Pads show traces of metal

splinters (check with magnet)

Metallurgical reaction of disc

material to disc pads

Actions:Replace Discs and Disc Pads.

Problem Solving:

ObservationsMetal Pick-up

Discs badly scored

Pads show traces of metal

splinters (check with magnet)

Metallurgical reaction of disc

material to disc pads

Actions:Replace Discs and Disc Pads.



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High Spots on dics

Points of discoloration at a

radius usually equally

spaced

Calipers not functioning

properly

Discs not skimmed correctly

Actions:

Check Calipers

Re-skim Discs or replace Discs



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Discs Over Skimmed (too thin).

Warping.

Cracking.

Disintegration.

Lack of observation by skimmer.

Poor vehicle management.

Action:

Replace Discs.


Discs Over Skimmed (too thin).

Warping.

Cracking.

Disintegration.

Lack of observation by skimmer.

Poor vehicle management.

Action:

Replace Discs.



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Pads not fitted correctly.Backing plates bent.

Pads badly worn (tapered).

Lack of training.

Poor workmanship.

Actions:

Training requiredReplace disc pads correctly.


Pads not fitted correctly.Backing plates bent.

Pads badly worn (tapered).

Lack of training.

Poor workmanship.

Actions:

Training requiredReplace disc pads correctly.



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Light duty trouble shooting

Problem solving: Observation

Cracked padsPads flexingPads not free to move

Piston bent in back plate

Actions:

Replace pad set


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Problem Solving:

ObservationsIncorrect pads fitted

Damaged pads

Friction material lose

from back plate

Actions:

Training requiredReplace disc pads

correctly



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Pads surface glazed.High temperature at

short durations

Actions:

Correct by normal use


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Light Duty Trouble ShootingProblem Solving:

ObservationsDenaturing.

Whitish outer edge.

(denaturing)

Excessive temperature due to

intensive use or dragging

Actions:If minor damage pads can be

re-used but recommendreplacement


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Documents

Fitment Centre Training Part 4