1968 MERCURY COMET

Typical onset: 80,000-120,000 mi

Symptoms: Rattling noise from front of engine on cold starts that disappears when warm, Rough idle and poor performance due to retarded cam timing, Check timing marks — cam gear off by several degrees indicates stretch, Catastrophic failure rare but possible, leading to valve-to-piston contact on some engines

Fix: Replace timing chain, gears, and tensioner. On V8s, 4-6 hours labor including setting timing and checking oil pump drive. I6 engines slightly less time. Smart shops replace the nylon cam gear teeth regardless of appearance — they deteriorate with age.

Estimated cost: $400-800

Symptoms: Visible rust perforation in front floor pans, especially driver side, Rear torque boxes (where rear leaf springs mount) show surface rust or structural rot, Trunk floor rust-through near wheelwells, Frame rails behind front wheels develop scale and holes in rust-belt cars

Fix: Patch panels available but proper repair requires cutting out rust and welding in new metal. Floor pans: 8-12 hours per side. Torque boxes are structural and critical for safety — 6-10 hours each side if replacement sections available. Many cars have had amateur repairs that look okay but aren't structural.

Estimated cost: $1,200-4,000

Typical onset: 70,000-100,000 mi

Symptoms: Excessive play at steering wheel (more than 2 inches at rim), Wandering on highway requiring constant correction, Clunking feeling through wheel when turning from center, Adjustment of sector shaft only helps temporarily

Fix: Rebuild kits available but worn boxes often need replacement. Used boxes are plentiful. Replacement takes 3-4 hours including alignment of steering column and drag link. Check pitman arm splines and idler arm simultaneously — typically worn at same interval.

Estimated cost: $350-650

Typical onset: 60,000-90,000 mi

Symptoms: Clunking over bumps from front end, Tire wear on inside or outside edges, Steering wander and poor return to center, Visible vertical play when prying under tire with car jacked up

Fix: Upper and lower ball joints plus idler arm should be done together. Uppers are riveted from factory — need drilling out and bolting in replacements. 5-6 hours for both sides plus idler arm, then alignment. These cars have no sway bar on base models, making tight ball joints critical for handling.

Estimated cost: $600-1,000

Typical onset: 50,000+ mi

Symptoms: Coolant weeping at front or rear of intake manifold, Slight loss of coolant with no external drips — leaking into crankcase, Milky oil or coolant in oil if leak is severe, Vacuum leak causing rough idle if gasket fails at port

Fix: Remove intake manifold, clean all surfaces thoroughly, install new gaskets with proper RTV at end rails. 4-5 hours labor. The small-block Ford end seals are notorious for weeping if not installed correctly with the right sealant. Use Fel-Pro gaskets, not the cheap composite sets.

Estimated cost: $350-600

Typical onset: varies — age-related

Symptoms: Soft brake pedal that goes to floor with repeated pumping, Brake fluid leak visible on booster or down firewall, Internal seal failure causing loss of all braking with no warning

Fix: Replace master cylinder. 1968 uses single-reservoir design — complete brake failure possible if it fails. Upgrade to dual-reservoir 1969+ unit highly recommended for safety (direct bolt-on). 2-3 hours including bleeding entire system. Check all wheel cylinders and flex lines while system is open.

Estimated cost: $200-400

Symptoms: Ammeter shows discharge at idle or low RPM, Dim headlights at idle, brightening with RPM increase, Dead battery after short trips, Voltage regulator cycling rapidly (clicking sound)

Fix: 1968 still used generators on base models — brushes wear out and output drops. Rebuild takes 2 hours but conversion to alternator is smarter: $150 in parts, 3 hours labor including bracket fabrication or adapter. Check for corroded bullet connectors in charging circuit — common failure point that mimics bad generator.

Estimated cost: $250-500