Hercules GTA4800 — To remove the cylinder head
Repair & overhaul
For the Hercules GTA4800, from the Hercules service manual.
Applies to: Hercules G4800 series engine
Before you start
- Do not pry on the contact surfaces.
Procedure
- Drain radiator and remove water thermostat housing, hoses, water manifolds; disconnect water temperature gauge thermocouple.
- Disconnect exhaust pipe.
- Disconnect air cleaner or pipe from turbocharger and remove.
- Shut off gas supply line to engine; disconnect gas supply line at engine.
- Remove cylinder head covers, rocker arm assemblies and push rods; remove turbo exhaust manifold and intake manifold.
- Remove cylinder head nuts and lift cylinder heads; tap lightly with soft hammer if necessary; do not pry on contact surfaces.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Cylinder head torque: Step 1 110 ft. lbs.; Step 2 130 ft. lbs.; Step 3 157 ft. lbs.; Step 4 re-torque 157 ft. lbs.
Source: Hercules service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.