Coolant System Checklist
Maintain engine health with this comprehensive coolant system checklist. Learn to inspect levels, hoses, and radiator components to prevent overheating and costly repairs.
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| Item | Priority | Who | Time | What to check (Pass/Fail) | If failed (Next step) |
|---|---|---|---|---|---|
| Coolant Level (Reservoir) | Required | DIY | 2 min | Between Min and Max marks | Top off with correct fluid |
| Radiator Cap Seal | Required | DIY | 3 min | Gasket is soft, no cracks | Replace cap immediately |
| Upper Radiator Hose | Required | DIY | 5 min | Firm but pliable; no bulges | Replace hose and clamps |
| Lower Radiator Hose | Required | DIY | 5 min | No collapses or soft spots | Replace hose |
| Coolant Color/Clarity | Recommended | DIY | 2 min | Bright color; no oil or rust | Flush system; check head gasket |
| Radiator Fins | Recommended | DIY | 5 min | Clear of debris; no bent fins | Clean with low-pressure water |
| Water Pump Weep Hole | Required | DIY | 10 min | Dry; no crusty residue | Replace water pump |
| Heater Core Hoses | Required | DIY | 5 min | No leaks at firewall entry | Tighten clamps or replace |
| Thermostat Housing | Recommended | DIY | 5 min | No white/pink crusty buildup | Replace gasket or housing |
| Coolant pH/Strength | Recommended | DIY | 5 min | Protection to -34F or better | Drain and refill coolant |
| Electric Fan Operation | Required | DIY | 10 min | Turns on at temp or with A/C | Check fuse, relay, or motor |
| Overflow Hose | Optional | DIY | 2 min | Clear; no clogs or cracks | Clean or replace small hose |
| Cabin Heater Output | Recommended | DIY | 5 min | Blows hot air when requested | Check for air pockets or clog |
| Drive Belt (Water Pump) | Required | DIY | 5 min | No fraying; proper tension | Replace serpentine belt |
| Radiator Mounts | Optional | DIY | 3 min | Radiator is secure; no play | Replace rubber bushings |
| Head Gasket Signs | Required | DIY | 5 min | No white smoke from exhaust | Professional engine diagnostic |
| Coolant Temp Gauge | Required | DIY | 5 min | Stays in middle; no spikes | Check sensor or thermostat |
| Pressure Test | Recommended | Shop | 30 min | Holds pressure for 15 mins | Locate and seal hidden leak |
Use this table as a guide during your monthly vehicle walk-around. Checking these items regularly allows you to monitor the degradation of rubber components and the chemical health of your coolant.
If you are uncomfortable performing any of these steps, especially those involving the water pump or pressure testing, consult a certified technician. Keep a log of any fluid you add to track potential slow leaks.