Digger or Tractor Overheating? Clean, Fix or Replace the Radiator

Your digger or tractor keeps running hot, or the radiator is holed or weeping. Rule out the cheaper causes first, clean the core properly and decide whether a repair will do. If it has to be replaced, match the new one by OE number, model, serial number and size.

The Radiators range at PartsForMachines has more than 300 Highway Automotive radiators for JCB, Caterpillar, Komatsu, Case, New Holland and John Deere machines, plus forklifts and trucks.

Why Does My Digger or Tractor Keep Overheating?

Several faults can make an engine run hot, and the radiator is only one of them. A core caked with mud, leaves or fine dust, low coolant from a leak, a fan or fan drive that is not working, or a thermostat stuck shut can all do it.

Work through them cheapest first: check the coolant level and look for leaks, clean the core, check the belt and fan, then test the thermostat (see the FAQs). A new radiator only cures overheating when the radiator itself leaks, is damaged or is blocked inside.

How Do I Clean a Clogged Radiator Properly?

Blow the dirt out of the fins against the normal airflow, so it is pushed back out the way it went in. Use low-pressure compressed air or a gentle stream of water, and keep the nozzle back from the core, because high pressure can damage the fins.

Where another cooler, such as the hydraulic oil cooler or air-con condenser, sits in front of the radiator, clean the gap between them too: debris collects there and still blocks the air. If the machine still runs hot after a thorough clean, check for a blockage inside the core before you consider a bigger radiator.

Should I Repair, Re-core or Replace a Leaking Radiator?

A single leak in a copper-brass radiator is worth showing to a radiator specialist, who can also say whether a re-core makes sense. Highway Automotive notes that copper-brass construction is well regarded for repairability.

Stop-leak is a stopgap at best, as sealer can block the narrow passages in some radiators. If the core leaks in several places, is blocked inside or has taken a knock, weigh the cost and downtime of a repair against a new radiator.

How Do I Find a Replacement Radiator That Fits My Machine?

Start with the OE part number from the old radiator or the parts book, then confirm the model, serial number and size. The 10118003 radiator for the JCB 1CX, for example, cross-references OE 30917000 and measures 455 x 450 x 59 mm, height by width by depth.

The model name alone is often not enough. Our range has eight radiators for versions of the JCB 3CX, from 540 to 630 mm wide and in three core materials. Where one radiator covers a family, such as the 10118004 radiator for the JCB 2CX, 3CX and 4CX, check your exact variant and serial number before you order.

What Should I Check Before I Order?

• the OE part number, from the old radiator or the parts book
• the machine make, model and serial number, plus the engine variant if one radiator covers several models
• the size of the old core (height x width x depth) and where the hoses connect
• whether it has a frame or fan cover, and which grommets and fittings you will reuse or buy
• the coolant type and mix your engine maker specifies, ready for the refill

Browse the Radiators range, or contact the PartsForMachines team by WhatsApp, telephone or email with the machine model, serial number and any number on the old radiator. A photo of the old unit and its hose connections helps too.

Product options, delivery options and returns terms are shown on each product page. A 30-day return policy applies to eligible items.

Frequently Asked Questions

How do I check if the thermostat is stuck shut?

As the engine warms up, the top hose should get hot once the thermostat opens; if it stays cool, suspect the thermostat. To confirm, take it out and heat it in a pan of water to see whether it opens.

How can I tell if a radiator is blocked inside?

With the engine hot and idling, scan the core with an infrared thermometer. Blocked areas show up as cool patches, because coolant is not flowing through them. If a flush does not clear them, the core needs taking out for cleaning, or replacing.

Will flushing clear a blocked radiator?

Sometimes. A thorough backflush can clear a radiator that is only lightly blocked, but not every part of a cooling system can be rinsed clean. If cool patches remain afterwards, have the core cleaned professionally or fit a new radiator.

How do I check the cooling fan is working?

Check that the fan belt is tight and the blades are undamaged, then watch the fan as the engine heats up. A viscous fan clutch that has lost fluid can stop engaging and let the engine overheat, so have a suspect fan drive tested.

What do C/B, A/A and P/A mean in a radiator's specification?

They describe the build. C/B is copper and brass. A/A is all aluminium, as on the 10115002 Hitachi ZX 450 radiator. P/A is plastic and aluminium (an aluminium core with plastic tanks), as on the 11118026 JCB Fastrac radiator.

Does a new radiator come with a frame, fan cover and grommets?

Not always, so check the product name and box contents. More than 50 are sold without a frame and many exclude grommets, so plan to reuse or buy fittings. Some include extras: the 10136016 Claas Arion radiator comes with its fan cover.

Will a replacement radiator bolt straight in?

It should if it matches the OE number and the old radiator's size. Many are made to the original dimensions so they fit the existing mounting points and hose connections without modification. Compare the hose outlets with the old unit before fitting.

Should I flush the cooling system when fitting a new radiator?

Yes. Flush out old coolant, scale and debris so they do not foul the new core. Then refill with the coolant type and concentration your engine maker specifies, bleed out any air and check for leaks before the machine goes back to work.

What makes a radiator fail in the first place?

Apart from knocks and holes, corrosion can make a radiator fail, and contaminated, wrong or worn-out coolant can lead to it. Use the coolant your operator's manual specifies, change it at the stated intervals and check the radiator on your daily walk-round.