How to Install Small Block Chevy Valve Covers? | 6-8 Lb-Ft

Small-block Chevy valve covers seal best when the head rail is clean and the bolts are torqued evenly to 6-8 ft-lb on factory-style covers.

An oily valve cover seam on a small-block Chevy is usually the result of overtorqued bolts, not a worn-out gasket. Learning how to install small block Chevy valve covers properly takes about an hour, and the payoff is a dry engine and no drip spots on the driveway.

Step-by-Step: Small-Block Chevy Valve Cover Installation

The installation is straightforward: remove the old cover, clean the head sealing rail, fit a fresh gasket, seat the cover, and torque the bolts evenly. Chevrolet’s procedure for its die-cast rocker covers says to work one valve cover at a time so the valvetrain is never fully exposed.

1. Clear the area. Let the engine cool, then pull anything that blocks the cover. Chevrolet notes that air-conditioning brackets on some cars may need to be removed to clear the cover.
2. Remove the old cover and old gasket. Scrape every piece of gasket material off the cylinder head rail. Use a plastic scraper on aluminum heads to avoid cutting the surface. Both Chevrolet’s guide and the Jegs adapter instructions treat this cleaning as a required step, not a courtesy.
3. Fit the correct gasket. On Chevrolet’s die-cast covers, the rubber gasket does not need adhesive to stay on the cover. Some aftermarket kits use LS3-style or proprietary gaskets instead of traditional cork/rubber pieces, so confirm the kit actually includes the gasket it needs before you start.
4. Start the mounting bolts. Set the cover in place with its four bolts, washers, and rubber grommets started loosely. Rubber grommets isolate the cover from the bolt and keep the torque from crushing the flange.
5. Torque in the right sequence. Tighten the bolts from the center outward to 6-8 ft-lb, then repeat the process on the other side.

Before final torque, confirm that hoses, wires, and PCV or breather fittings are not trapped under the cover and that any ventilation hardware is reinstalled correctly. If a cover barely clears the rocker arms, aftermarket instructions often call for a modeling-clay clearance check and hand-rotating the engine before you button it up.

What Torque Specs and Gaskets Do You Need?

There is no single torque number for every small-block Chevy cover; the mounting style decides it. Factory-style perimeter bolts use low torque because the thin covers distort easily and the gasket crushes fast. Center-bolt covers and adapter-plate systems have their own specs, so the kit’s instructions always override a generic number.

For Chevrolet’s die-cast covers, the spec is 6-8 ft-lb, confirmed in Chevrolet’s small-block rocker cover installation guide. Use a low-range torque wrench here; 8 ft-lb is easy to overshoot with a full-size ratchet. Aftermarket adapters work differently: Jegs says to torque adapter nuts to 75 lb-in, the small studs to 20 lb-in, and the cover nuts to 65 lb-in. Some aftermarket kits require gaskets not included in the box, and others call for replacing factory hardware with the specified part number, so read the parts list before starting.

If you are buying new covers instead of reusing stock pieces, our tested roundup of the best 350 small block valve covers compares fit, gasket type, and clearance issues before you spend money.

Sealant rules change with the setup. Chevrolet says its rubber gaskets need no adhesive. The Jegs adapter instructions say to keep sealant off the O-ring side of the adapter. Some aftermarket covers with outside-perimeter bolts on aluminum heads specifically require sealant in designated slots around the bolt holes. Read the kit’s instructions before reaching for RTV, because the wrong sealant causes more problems than it fixes.

Common Mistakes That Cause Leaks

Most valve-cover leaks trace back to overtorquing, leftover gasket material, or a part that doesn’t fit. Chevrolet’s 6-8 ft-lb spec sounds low, but thin covers distort quickly and a crushed gasket leaks worse than an under-torqued one.

• Overtorquing. More torque does not mean a better seal; it means warped covers, crushed gaskets, and stripped cylinder head threads.
• Cleaning only part of the rail. One old chunk of gasket on the head creates a gap no new gasket can fill.
• Skipping the clearance check. Rocker arms, studs, or PCV baffles can contact the cover and keep it from seating, which shows up as a leak once the engine warms.
• Using the wrong sealant. Rubber gaskets usually go in dry. Sealant belongs only where the kit specifies it, such as the bolt-hole slots on some perimeter-bolt aluminum-head covers.

Work one side at a time, torque in the center-out sequence, and reinstall every PCV and breather hose before you call the job done.

FAQs

Can I reuse valve cover gaskets?

A fresh gasket is almost always worth the few dollars. Once a rubber or cork gasket has been compressed, it rarely seals evenly a second time, and redoing the job costs far more than the part. The only exception is a gasket you installed and removed without any oil exposure or compression.

Should I use RTV sealant on valve cover gaskets?

Only if the cover kit tells you to. Chevrolet’s die-cast cover guide states that its rubber gaskets need no adhesive, while some aftermarket perimeter-bolt covers on aluminum heads call for sealant in specific slots around the bolt holes. When no sealant is specified, a dry gasket seals better than an over-smeared one.

What happens if I overtighten valve cover bolts?

Overtightening warps the cover flange and compresses the gasket past its useful range, which is exactly how leaks start. It can also strip cylinder head threads, turning a quick gasket swap into a thread repair. Use the low torque spec with a torque wrench every time.