If your Honda Acty is overheating, leaking coolant, or showing signs of corrosion near the radiator fins or tanks, it may be time to replace the radiator. Whether you drive a carbureted HA3/HA4 or fuel-injected HA6/HA7 model, a properly functioning radiator is critical to keeping your mini truck or van running reliably—especially in warmer climates or under load. This step-by-step guide will walk you through how to remove and install a new radiator, what tools you’ll need, tips to avoid common mistakes, and the correct part numbers for your specific Acty model.
???? Tools & Supplies You’ll Need
???? Basic Tools:
10mm and 12mm socket set
Phillips screwdriver
Flathead screwdriver or trim removal tool
Pliers (for hose clamps)
Coolant drain pan
Torque wrench (optional but helpful)
Jack and jack stands or ramps
???? Recommended Supplies:
Pre-mixed Honda Type 2 coolant (or 50/50 ethylene glycol mix)
New radiator cap (OEM recommended)
Replacement hoses or clamps (if brittle/cracked)
Gloves, rags, and safety glasses
Optional: spill-free funnel or air bleed kit
???? Common Radiator Part Numbers by Model
| Model | Engine | Radiator Part Number (OEM Equivalent) |
|---|---|---|
| HA3 / HA4 | E05A | 19010-PZ3-003 or aftermarket: TYC 2273 |
| HA6 / HA7 | E07Z | 19010-PFB-003 or aftermarket: KOYO or Denso 221-3404 |
???? Tip: Always verify with your VIN or chassis number before ordering parts to ensure proper fit.
???? Step-by-Step: Replacing the Radiator
1. Allow the Engine to Cool
Never open the radiator cap on a hot engine. Let the vehicle cool completely—preferably overnight.
2. Raise the Vehicle and Locate the Radiator
On most Honda Acty models, the radiator is located in the front of the vehicle, under the cab floor, behind a plastic grille or access panel. Raise the front end on ramps or jack stands for easier access.
3. Drain the Coolant
Place your drain pan under the radiator.
Remove the radiator cap and drain plug at the bottom of the radiator.
You can also remove the lower hose if there's no drain plug.
Dispose of coolant properly—never pour it down the drain.
4. Remove the Front Grille or Access Panel
Use a screwdriver or trim tool to remove clips or screws.
Gently pull off the panel to expose the radiator and fan shroud.
5. Disconnect the Hoses
Use pliers to remove the upper and lower radiator hose clamps.
Twist hoses gently to break the seal—be careful not to damage the necks.
6. Disconnect the Fan (If Applicable)
Some Acty models have an electric fan mounted to the radiator:
Unplug the electrical connector
Unbolt the fan shroud from the radiator (usually 10mm bolts)
7. Remove the Radiator
Locate and remove the radiator mounting bolts or brackets
Carefully lift the radiator up and out of the engine bay
Watch for any hidden transmission cooler lines (on auto models, rare)
8. Install the New Radiator
Drop in the new radiator carefully—don’t force or bend fins
Reattach mounting brackets and torque bolts snugly
Reinstall the fan shroud and plug in the connector (if applicable)
Reconnect radiator hoses and clamps
9. Refill Coolant and Bleed the System
Slowly pour coolant into the radiator until full
Fill the overflow tank to the MAX line
Use a spill-free funnel or follow Honda’s bleeding procedure:
Set heater to HOT
Run engine at idle
Gently squeeze hoses to release air
Watch for air bubbles escaping the radiator neck
10. Reinstall the Cap and Test Drive
Once the coolant level stabilizes and no bubbles are present, reinstall the radiator cap
Take a short drive, monitor the temp gauge
Recheck coolant level after the engine cools down and top off if needed
⚠️ Common Mistakes to Avoid
Forgetting to bleed air – causes overheating
Using the wrong coolant – use silicate-free, Honda-compatible formula
Reusing brittle hoses or caps – may lead to future leaks
Skipping the fan connector – leads to instant overheating once hot
✅ Final Tips
Check the thermostat and radiator cap during this job—replacing them together can prevent future issues
If your old radiator shows signs of oil contamination, inspect for head gasket issues
Keep an eye on the temperature gauge for a few days after replacement
???? Want a Complete Radiator Kit?
We offer radiator kits for HA3, HA4, HA6, and HA7 models that include:
OEM-spec radiator
Upper and lower hoses
Radiator cap
Thermostat
Pre-mixed coolant
Hose clamps
contact us with your chassis code for the right fit.