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:
| BAD STARTING | |
| 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 |
| FUEL SYSTEMS | |
| 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 Flooding |
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 Tighten! 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 Readjust 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 Re-pump 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 |
Browse more Mini Mania DIY Articles
