How to Cure a Chronic Problem on a Perkins 4.108 engine
This Tech Tip, one in a series we publish, discusses the Perkins 4.108 rear seal leaking problem and our new innovative new seal that overcomes this chronic problem.
The original OEM rear seal supplied by Perkins for the Perkins 4.108 engine is made from cotton and is called a “rope” style seal. It is similar to what was used on post-war British MGs and Triumphs. While a leaking rear seal may be only an inconvenience in an industrial application, it becomes a major concern when used in marine applications. Using new polymer technology, we have improved on this material and now offer a Perkins 4.108 new rear seal package for the Perkins 4.108 that cures this chronic problem. Our replacement rope seals for the Perkins 4.108 are made from the highest quality nylon and are Teflon impregnated to ensure leak free sealing. However, close attention must be paid when trimming to avoid the fraying of material. Here is how to install our new rear seal for the Perkins 4.108/Westerbeke 40 engine.
Installation Procedures
- You do not need to pre-soak this material in oil as you would with the traditional Perkins 4.108 OEM rope rear seal
- Press the new Foley seal into place. Using a smooth rod, like a socket, lightly compact the material into both seal housings.
- Trim seal material leaving approximately .015″ of the seal protruding from the housing surface. Use the wood stick as backer when cutting the seal. Cut seal into wood backer to ensure a clean cut.
- Press protruding seal material downward so it’s flush with housing surface. Apply assembly lube to seal surface and re-assemble.
- Please Note: Apply gasket sealer to the area where to seal housing mates to the engine block. Do NOT apply gaskets sealer to the replacement seal.
