Jeep AMC 258 Cu. In./4.2 Liter 6 Cylinder Valve Cover
Part Number 8656
This PML Jeep valve cover benefits over stock valve covers:
|Black powder coating
Dimensions: The cover has approximately 3.7 inches from the gasket to the inside top surface. Other dimensions not available.
Finishes: Read about finishes and construction of PML parts.
Installation Instructions: PML Jeep 258 Valve Cover Installation Instructions.
PML designed our valve cover for the AMC 258 (4.2 liter) straight 6 engine based on the original valve cover as it came from the factory. We use sand-cast aluminum construction to provide strength and durability and a cast-in baffling system. The gasket flange is precision-machined and 0.200-inch thick for a uniform clamping force on the gasket.
The cover includes a billet oil fill cap for a secure seal and features holes for PCV and breather. The AMC Jeep 4.2 Liter/258 cubic inch engine comes in four possible fastener configurations. The PML valve cover works with all possibilities and has provisions for the use of studded bridges and head bolts. Holes can be easily drilled for studded rocker arm bridges. Reference the Installation Instructions.
PML's baffling system allows the engine to breath better then most. We have some street applications that do not run any breathers on our covers, and there is no blow by. This baffling system works very well as compared to others since we run along the side wall and pick up lower than most.
Blow-by is not a situation that any valve cover can stop. PML's Jeep valve cover can reduce the oil mist somewhat since the design is longer and there is a elbow that will usually separate the oil from the air, allowing it to drip down. The baffling is an integral part of the casting so there are no rivets or screws to vibrate loose.
Note: If your head has been modified (for example, the locator dowel pin holes have been drilled and tapped), our cover will not work for you.
The 258 engine was commonly used in 1971 to 1990 Jeep, AMC, Scout and some industrial vehicles.
This valve cover fits 1981-1986 heads.
This valve cover also fits 1987-1990 heads if your engine came with the plastic valve cover. If your 1987-1990 engine came with an aluminum valve cover from the factory, our valve cover will not fit your head. Engines with the aluminum valve cover have the same gasket shape and bolt pattern as the 4.0 heads. Look at the Installation Instructions for a view of the gasket shape and bolt pattern on this valve cover and verify it is the same as the valve cover you have.
This valve cover has been installed on CJs, Wagoneers, Wranglers, Eagles, and an AM General Ice Cream Truck.
Vehicle configurations vary so always check before ordering.
This is one of the stock OEM covers we used for development. The valve covers is from a 1986 Jeep CJ–7.
Click on image to view larger in a new tab or window..
1985 AMC Eagle
Matthew installed this PML valve cover on his 1985 AMC Eagle 6 cylinder. He said it made a "world of difference" going from the plastic cover to the PML cover.
1983 AMC Eagle
Walter installed this PML valve cover on his 1983 AMC Eagle Wagon 4x4 with 258 engine (4.2L). He email us images of his installation process. Our thanks to Walter for his careful picture taking during his installation. He also installed new rocker arm bridges when he replaced his valve cover.
1983 AMC Eagle 4x4 258
PML valve cover on 1983 Eagle 285 motor
Stock valve covers of a 1983 AMC Eagle
Replacing rocker arm bridges in 1983 AMC Eagle 4.2L/258 motor
The above installation has not been tried or verified by PML. PML does not recommend any of the above. Information for reference only.
PML Valve Cover Features
For a larger picture, please click one of the above images. A separate window will open showing a bigger picture. (The larger pictures take a minute to display.)
Learn more about finishes and construction of PML parts.
||PML, Inc. 201 W. Beach Avenue Inglewood, CA 90302 310-671-4345 www.YourCovers.com firstname.lastname@example.org||
Copyright 2000-2018, PML, Inc.