Troubleshooting Your Classic Mini

Use this handy troubleshooting guide to assess problems with your Classic Mini.  Bad starting, fuel system, steering, suspension & transmission.  Questions?  Contact our experts at 1-800-946-2642 or email us here.  We're happy to assist you!

Table of Contents:

Symptom & Cause Cure
1 Starter does not work
Lights dim -
battery flat
bad connections
starter jammed

Jump leads or charge battery

Clean and remake connections
Free starter from ring gear

2 Starter spins but not engine

Bendix drive stuck

Clean drive with fuel

3 Engine turns but won't fire

Distributor cap damp
Faulty spark plug wires
Burnt or wrongly gapped points

Cracking in distributor cap

Plugs flooded with fuel
Coil faulty
If lights dim battery low
Timing incorrect

Dry off and try again

Reconnect or replace plug wires
Clean and gap or replace points (more details)
Replace cap
Remove - dry - replace
Check with test bulb
Jump leads or recharge
Check timing

4 Misfiring, pinking, sluggish

Timing incorrect
Bob weights stuck

Incorrect fuel octane (pinking)
CB points dirty, burnt or wrongly gapped
Condenser faulty
Plugs worn or wrongly gapped
HT leads faulty and earthing

Check timing with strobe

Check advance with strobe - clean and free off
Go up one grade
Clean and regap points or replace
Fit new condenser
Clean and gap or replace
Check leads - replace

5 Engine cuts out on move

Faults as in (3) above except for wet plug

Test and remedy as in (3) above

Symptom & Cause Cure
1 Engine won't start cold
Lack of fuel at carburator - Empty tank!
Faulty fuel pump
Dirt in supply system
Carburator piston sticking
Needle valve stuck closed
Flooding - needle stuck open

Choke not closing fully
Air cleaner blocked

Check fuel pump - replace

Check for delivery - repair
Locate and clean points
Dismantle and clean
Clean and refit - replace
Remove and clean valve or replace if necessary
Adjust cable length and free of flap
Fit new air filter element

2 Engine won't start hot
As for (1) except choke
Badly worn bores and pistons

As for (1) except choke
Test compressions
3 Engine spits and dies
As for (1)
Vacuum in tank

As for (1) except choke
Remove cap - listen for hiss of air going in. Clear breather.

4 Ragged idling
Air leaks

Mixture wrong


Inlet manifold gasket - replace; Manifold loose - tighten; Carb flange - tighten and/or fit new gasket; Carb spindle worn - rebush or replace
Air filter - replace if clogged; Slow running - adjust
Needle valve (see No. 1 above). Set float height correctly.
5 Misfire at speed
Fuel starving - dirt or faulty fuel pump

Replace as necessary - clean or adjust

Symptom & Cause Cure

1 Brakes uneven/pull to side

Scored discs or drums
Pads or linings contaminated

Friction material different on one side (rare)
Seized pistons

Uneven shoe adjustment
Loose backplate or caliper
Shoe pull-off springs weak or broken on one side
Worn steering joints
Worn suspension

Have drums skimmed or replace
Check oil or fluid leaks and replace pads or shoes
Replace shoes or pads with
standard matched sets
Fit new wheel cylinder (s) or recondition caliper piston (s)
Manually adjust shoes
Tighten or replace if necessary
Replace springs

See steering section
See suspension section
2 Poor braking effect
Contaminated pads or linings

Master cylinder not efficient

One or more seized pistons
Servo (if fitted) faulty
Glazed friction surfaces

Fit new pads or shoes and find oil or fluid leak
Replace or recondition the master cylinder
As in (1) above
Replace servo or recondition
Best to replace pads or shoes after de-glazing

3 Pedal travel too long
Pads or linings worn down
Drum brake adjustment out
Air in hydraulic fluid
Master cylinder faulty
Distorted disc running out

Adjust or replace pads or shoes
Manually adjust shoes
Bleed system
Replace or recondition
Replace disc (more details)
4 Brakes squealing
Pads worn down
Disc perimeter rusted

Caliper piston (s) partly seized
Loose caliper (s)
Brake springs weak
Shims distorted

New pads just fitted

Replace pads
Clean with fine sand paper. Wipe out all dust.
Clean and/or replace piston (s)
Tighten bolts and check often
Replace springs
Replace shims - smear backs with HMP grease
Allow them to wear in
5 Pedal action spongy
Hydraulic fluid aerated

Bleed system and check for leaks

6 Persistant fluid loss
Leakage from unions
Cracks in flexible hoses
Leaking wheel cylinder (s)
Leaking caliper
Leaking master cylinder

Tighten unions
Replace hoses as necessary
Replace as necessary
Replace seals
Recondition or replace

7 Grabbing brakes or judder
Contaminated linings or pads
Discs or drums scored or distorted
Cheap friction material

See (1) above
See (1) above

Replace with recommended grade

8 Dragging brakes- binding
Shoe adjustment to tight

Handbrake adjustment tight

Pull-off springs weak
Pull-off springs incorrectly fitted
Seized piston (s) in caliper
Seized wheel cylinder (s)
Servo faulty

Slack off adjustment then adjust correctly
Slacken cable to give three or four clicks on ratchet
Fit new springs
Refit springs correctly

Clean and/or replace piston (s)
Fit new cylinder (s)
Replace or recondition
9 Brakes fade
Vapor lock in calipers or wheel cylinders
Friction material overheated by prolonged hard braking

Flush system and refill with fresh fluid
Allow to cool - don't restart too soon

Symptom & Cause Cure
1 Wander
Wheel imbalance
Incorrect tire pressures
Wheel bearings worn
Wheel nuts loose!
Worn steering ball joints
Wear in swivel hub base joints
Steering rack worn
Rack loose

Have wheels balanced
Correct pressures
Replace worn bearings
Replace joints
Adjust or replace
Replace if badly worn
Tighten and use a locking compound on the bolts

2 Steering wheel vibration
Road wheels not balanced
Uneven tire pressures
Bulge in tire wall
Tire incorrectly fitted
Buckled road wheel
Wheel nuts loose!
Steering joints worn
Suspension joints worn
Worn wheel bearings
Road wheel alignment out
Steering rack worn
Steering rack loose

Have wheels balanced
Equalize to correct pressure
Replace tire
Go back to tire shop!
Fit new wheel
As (1) above
Replace as necessary
Adjust or replace as necessary
As (1) above
Have alignment set
As (1) above
As (1) above
3 Steering pulls to one side
Road wheel alignment is out
Incorrect tire pressures
Brakes binding - drum
Brakes binding - disc

Have alignment set
Inflate correctly
Free off semi-seized piston

4 Steering action heavy
Low tire pressure
Dry or semi-seized steering joints
Swivel hub ball joints binding
Lack of lubrication in the rack
Steering alignment out
Steering rack adjustment too tight

Inflate correctly
Lubricate, if possible, or if a sealed joint, replace
Free off- replace if necessary
Lubricate with EP 90
Have alignment set
Readjust to the correct loading

5 Excessive steering pay
Worn in steering rack
Worn in steering joints
Loose rack

Adjust if possible, if not replace
Replace joints as necessary
Tighten and use a locking compound on the bolts

6 Shocks felt, steering wheel
Road shocks transmitted by over inflated tires
Competition springs fitted

Shock absorbers badly worn

Reduce to correct pressures

Live with it or swap back to standard springs

Replace with new units

Symptom & Cause Cure
1 Clonks/knocks from front
Front tie bar bushes worn or distorted
Hydrolastic pressure low
Weak rubber cone springs so body hits bump stop
Worn knuckle joints
Dampers not functioning properly
Replace as necessary

Fit new rubber cone springs

Fit new knuckles and ball sockets
Replace dampers

2 Clonks/knocks from rear
Shock absorber bushes worn
Shock absorber not functioning
Worn radius arm bearings
Worn knuckle joints

Replace bushes if dampers ok
Fit new dampers

Fit new bearings
Replace knuckle joints and ball sockets

3 Squeaks from suspension
Dry suspension/steering joints
Dry rubber bushes
Displacer valve in Hydrolastic displacer unit

Treat with silicone lubricant

Treat with silicone lubricant
Have anti-squeak additive pumped into fluid

4 Sagging to one side
Weak cone rubber spring
Hydrolastic unit under pressure

Replace weakened spring
Have pumped up to correct pressure

Symptom & Cause Cure
1 Clutch slip
Worn clutch disc
Contaminated clutch disc
Return stop adjustment incorrect
Fault in the hydraulics

Replace clutch disc
Replace clutch disc
Check and readjust
Locate and remedy leaks - slave cylinder, master cylinder, unions. Bleed.

2 Juddering on take-up

Clutch disc worn or distorted
Contaminated clutch disc
Soggy engine mountings
Engine tie-bar bushes defective or maladjusted
Broken torque spring in clutch disc

Replace clutch disc

Replace clutch disc
Replace as necessary
Replace or adjust

Replace clutch disc

3 Grabbing or snatching
Return stop adjustment incorrect
Fault in the hydraulics
Friction plate contaminated or distorted through heat

Check and readjust

As (1) above
As (2) above

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