Holts WondarWeld 500ml (Pack of 6) – Permanent Engine Block & Cylinder Head Crack Sealer Box

Holts WondarWeld 500ml (Pack of 6) – Permanent Engine Block & Cylinder Head Crack Sealer Box

Permanently repair internal cracks in cast iron, aluminum, and steel engine blocks without costly mechanical teardown using Holts WondarWeld 500ml (Pack of 6). Engineered for mechanical workshops, fleet maintenance depots, engine rebuilders, and motor spares stockists across South Africa, this heavy-duty metallic sealing solution bonds directly to damaged metal surfaces under high thermal and hydraulic pressure to restore engine compression and eliminate coolant loss.

High-Temperature Metallic Thermal Weld Action

Cracked cylinder heads, porous engine blocks, and minor head gasket leaks allow pressurized coolant to enter combustion chambers or oil galleries, leading to white exhaust smoke and overheating. Holts WondarWeld circulates through the water jacket and seeks out heat-stressed fractures. Upon contact with extreme combustion temperatures and atmospheric exposure at the crack site, it cures into a permanent, high-strength metallic weld seal that withstands intense engine operating pressures and vibrations.

Safe Circulation Without Cooling System Blockages

Unlike low-grade fibrous stop-leaks that can clog narrow radiator tubes or heater matrix cores, Holts WondarWeld remains completely liquid while circulating in clean water. It only hardens at the exact point of leakage where thermal and pressure differentials occur, ensuring unobstructed coolant flow across modern and classic engine cooling architectures.

Bulk Workshop & Fleet Maintenance Supply

• Workshop Box Value: Six individual 500ml bottles provide essential on-hand inventory for mechanical workshops, breakdown recovery services, and commercial spares counters.

• Multi-Metal Engine Compatibility: Safe and effective on cast iron, aluminum alloy, and steel engine blocks and cylinder heads.

• Cost-Effective Alternative to Teardown: Saves hours of labor and expensive machine shop disassembly on hairline block fractures and minor head gasket seepage.

Key Performance Features

• Value-Added 6-Pack Box: Includes 6 x 500ml bottles for professional workshop stock or fleet maintenance.

• Permanent High-Heat Seal: Forms a rock-hard metallic bond at crack sites that resists extreme thermal cycling and pressure.

• Non-Clogging Liquid Formula: Circulates freely through water pumps, thermostats, and radiator cores without causing blockages.

• Universal Engine Metal Safety: Compatible with aluminum, cast iron, and steel cylinder blocks and heads.

• Multi-Part Cross-Reference: Matches barcode 5010218345072, additional codes 0.000, 0.800, and cross-reference codes 6001600000180, CH616, and WW6.

Technical Specifications Matrix

Recommended Application Guidelines

1. Ensure the engine is cold, then drain the cooling system completely and flush thoroughly with clean water (Holts WondarWeld must not be mixed with anti-freeze or other radiator additives during treatment).

2. Remove the thermostat if necessary to ensure immediate, unrestricted circulation through the engine block.

3. Shake the Holts WondarWeld 500ml bottle vigorously, then pour the required dosage directly into the radiator or top hose (do not pour into the expansion header tank unless it is part of the pressurized flow).

4. Top up the system with clean water, start the engine, and run at a fast idle for 15–30 minutes until normal operating temperature is reached and the leak stops.

5. Allow the engine to cool completely, drain the WondarWeld/water solution, flush lightly with clean water, reinstall the thermostat, and refill with fresh water and Imoto Anti-Freeze coolant.

Mechanic's Critical Rule: Never leave anti-freeze in the cooling system when applying Holts WondarWeld! Glycol-based coolants prevent the metallic sealing agents from curing properly at the crack site.

What's In The Box?

• 6 x Holts WondarWeld Engine Block & Cylinder Head Repair 500ml Bottles (Pack of 6 Box)

Delivery Across South Africa

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