2004.5-2005 Duramax Stock Reman Heads (PDM-LLYSH)

Fits

The Industrial Injection LLY Duramax Stock Remanufactured Heads are designed to be a factory replacement. Complete ready to bolt on.

Part Number:  PDM-LLYSH

• Direct Replacement
• Diamond Honed Guides
• Unshrouded Valves
• High Strength Alloy, Heat Treated iron based valve guides
• Premium valve seat inserts made from a true Nickel Based Non-Magnetic material
• Multi-angle valve job
• New valve springs

• Sold in a pair
• Some of these heads are converted from LBZ/LMM heads because of the lack of quality LLY head cores. You will need to use LBZ/LMM Glow plugs.
• To receive full core credit cylinder heads need to be a good, re-useable pair of cylinder heads. No cracks, warping, or excessive wear.

Heads are first jet washed in a high-pressure spray cabinet to remove oil and dirt, then glass beaded to remove carbon. Next, they are checked by magnafluxing, (cast iron only) or pressure testing. They are visually inspected for defects that would make them unusable.

New High Strength Alloy, Heat Treated iron-based valve guides are installed. These guides are heat treated to Rockwell 22 Scale, which produces the ultimate in wear resistance. This is far superior to original guide material, including Bronze. The guide incorporates a spiral grove inside the guide to hold oil and aid the lubrication of the valve during engine operation.

Guides are then honed (not reamed) to exact size using a diamond honing mandrel. Diamond abrasives allow for consistency of size, surface finish, and bore geometry with no variation from guide to guide. The guide size is then verified using a valve guide bore gauge.

As needed the head receives new Premium valve seat inserts made from a true Nickel Based Non-Magnetic material that was developed for extreme operating conditions.

Next, the head is treated with a multi-angle valve job to help maximize the flow of air in and out of the head. This is accomplished using a Serdi 100 guide and seat machine. Serdi uses a solid carbide straight shank pilot. When inserted into the valve guide, it simulates the real valve stem during the centring process. This guarantees the valve seat is finished for a perfect valve-to-seat match.

Using CBN or Diamond tooling the head is given a new surface. With Industrial Injections Berco Milling machine they can control the surface finish to accommodate different head gasket types. For example, MLS head gaskets require a very smooth surface finish.

Finally, the head is jet washed dried and assembled with new valve seals and new valve springs.