Here's a breakdown of the likely cause and how to fix it:
Cause:
* Worn Valve Cover Gasket: This is the most probable culprit. Over time, the gasket hardens, cracks, and loses its sealing ability. Heat, age, and engine vibration contribute to this degradation.
How to Fix It:
This is a relatively common repair, but it's best approached systematically:
1. Gather Supplies: You'll need a new valve cover gasket (make sure it's the correct one for your 3.2L V6), a new tube of gasket sealant (high-temperature silicone is recommended), a socket set, wrenches, a clean rag or shop towels, and possibly a torque wrench (to tighten bolts to the manufacturer's specifications). It's also wise to have fresh spark plugs on hand as they'll likely need replacing since they've been exposed to oil.
2. Disconnect the Battery: Always disconnect the negative (-) terminal of your battery before starting any work on your vehicle's electrical system.
3. Remove the Valve Cover:
* Disconnect Spark Plug Wires: Carefully disconnect the spark plug wires from the spark plugs, marking each wire so you know where it goes back to.
* Remove Spark Plugs: Remove the spark plugs.
* Loosen and Remove Valve Cover Bolts: Carefully loosen and remove the bolts securing the valve cover to the cylinder head. Note their positions and tightening sequence if possible.
* Lift Off Valve Cover: Gently lift the valve cover off. There might be some resistance from old gasket material.
4. Clean the Surfaces: Thoroughly clean the valve cover and cylinder head mating surfaces. Remove all traces of the old gasket material. Use a gasket scraper if needed, but be careful not to scratch the surfaces. Cleanliness is crucial for a good seal.
5. Apply Gasket Sealant (if needed): Some gaskets come with pre-applied sealant. Check your new gasket instructions. If not, apply a thin bead of high-temperature silicone sealant to the mating surfaces according to the instructions on the sealant tube. This helps ensure a perfect seal.
6. Install the New Valve Cover Gasket: Carefully position the new valve cover gasket onto the cylinder head. Make sure it's seated correctly.
7. Reinstall the Valve Cover: Carefully lower the valve cover onto the gasket and cylinder head.
8. Tighten the Bolts: Tighten the bolts in the correct sequence (consult your repair manual) to the manufacturer's specified torque. Over-tightening can damage the cylinder head or valve cover.
9. Reinstall Spark Plugs and Wires: Install the new spark plugs (if you replaced them) and reconnect the spark plug wires, ensuring they are correctly seated.
10. Reconnect the Battery: Reconnect the negative (-) battery terminal.
11. Check for Leaks: Start your engine and let it run for a few minutes. Carefully inspect the valve cover area for any leaks. If you see any, you may need to tighten the bolts or, in a worst case, redo the gasket installation.
Important Considerations:
* Repair Manual: A repair manual specific to your 1994 Isuzu Trooper is highly recommended. It will provide detailed instructions, torque specifications, and diagrams.
* Professional Help: If you're not comfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Improper repair can lead to further engine damage.
* PCV Valve: While unlikely to be the sole cause of oil in the spark plug wells, a faulty Positive Crankcase Ventilation (PCV) valve can contribute to excessive crankcase pressure, which might exacerbate the oil leakage. Consider checking and replacing it as part of preventative maintenance.
Oil in the spark plug wells is not something to ignore. Addressing this issue promptly will prevent potential engine damage and maintain the health of your Isuzu Trooper.
