1991 Nissan Sentra Aluminum Exhaust Header Gasket

Do I need to clean the manifold and cylinder head surfaces before installing this gasket?

Yes. Scrape away old gasket material and carbon buildup from both the manifold flange and cylinder head surface. A clean, flat seating surface ensures the new gasket seals properly and prevents exhaust leaks.

What torque spec should I use when bolting the manifold back down?

Refer to your vehicle's service manual for the correct manifold bolt torque sequence and final spec. Over-tightening can crush the aluminum gasket; under-tightening will cause leaks.

Can I reuse the old manifold bolts, or do I need new ones?

Manifold bolts are typically reusable if they're not stripped or damaged. Inspect threads and bolt heads before reinstalling. If any bolt spins without catching, replace it to ensure a tight, even clamp load across the gasket.