Symptoms
Coolant loss, overheating, combustion gases in the coolant (confirm with a block test kit) and coolant weeping at the head-to-block joint.
The fix, step by step
- Confirm with a combustion leak test first.
- Pull the head and have it checked for flatness, decked and pressure-tested.
- Shops also commonly do a valve job and new valve seals.
- Use a valve-grind gasket set, an EGR gasket, a water-return pipe gasket, a distributor O-ring and FIPG.
- OEM gaskets are the forum default.
- Cometic MLS gaskets need very flat, finely finished surfaces.
- Inspect the timing chain tensioner and the plastic guides while it's apart, because they can break, especially on 1993–early 1994 engines.
- Some owners wish they'd replaced the head studs too.
Tools & part numbers
- Full metric socket set
- torque wrench
- engine hoist (optional)
- combustion leak tester
- FSM
- gasket set and FIPG
Where to buy the parts
Engine gasket sets and head gaskets (1997 LX450 catalog)RockAuto ↗
Exhaust manifold-to-head gasket set, 1FZ (EGEX171FZSET)CruiserTeq ↗Amazon ↗
Valve cover gasket kit, 1993–1997 1FZ (VCC66020KIT)CruiserTeq ↗Amazon ↗
Thermostat gasket, FZJ80/LX450Cruiser Corps ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Lexus LX 450 parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.