The Ford Triton 3-valve engines use COP ignition along with a unique spark plug design. The tip extends a full inch (25mm) below the seat, and it’s enclosed in a heavy-gauge stainless-steel sheath that includes the ground electrode. Above that, the tapered seat is a larger diameter (mild) steel ring extending 1/2" (13mm) below the threads. The design is intended to keep the threads away from the heat of the combustion chamber.
Unfortunately, carbon deposits build up between the extended sheath and the cylinder head. Attempting to remove the spark plug without first dissolving that carbon will cause the plug to break off just below the threads, leaving the seat ring, ceramic tip and sheath stuck fast in the hole. Sometimes the threads in the cylinder head are damaged too. Fortunately, there are tools and procedures for extracting these pieces and repairing the threads without removing the cylinder head.
Many service bulletins have been issued to address this problem. The most important bulletin is 08-1-9, which explains how to remove the spark plugs without breaking them. Many people report success using that procedure. The latest bulletin describing the extraction procedure and tools is 08-7-6, and TSB 07-21-2 describes latest thread repair procedure and tools.
The Ford spark plug extractor tool is Rotunda 303-1203, also known as the OTC 303-1203. Other well-known vendors make tools designed for the same job, and while some are a little easier to use, each will get the job done. The step-by-step instructions are pretty clear and helpful, but we have learned a few tips from the field.
First of all, follow the instructions carefully; don’t rush the job or omit any steps. The first steps will remove or push the broken porcelain down into the end of the sheath, making room for the extractor tool. Secondly, get some heat into the broken sheath. One user of this tool ground down a length of all-thread rod to fit precisely into the sheath, using the sheath from one of the other old plugs to check the fit. Then he heated the rod with a torch and inserted it into the sheath.
Once the extractor gets a good bite on the sheath, it still might not move. A VERY slight tap may break it loose. Remember, it’s the carbon built up around the sheath that’s holding it in place.
Triton engines are also known for spark plug thread failures, to the point of actually spitting the plug out of the engine. Ford TSB 07-21-2 provides information about a Rotunda tool for repairing the threads without removing the cylinder head, and Ford also approves the use of a Lock-n-Stitch Full-Torque thread repair kit. This kit has hardened aluminum inserts that are stronger than the original threads, and Ford says they provide the proper heat transfer from the spark plug. The kit will work on all Triton (Modular) engines made since 1991.
The kit’s instructions are complete and well illustrated. One item that requires special attention is measuring the spark plug hole seat.
Three different seat shapes were used in these engines, and there are different inserts for each seat shape. The only way to tell which insert to use is to measure the undamaged seat of another spark plug hole with a special gauge provided in the kit. The gauge and the measuring process are complicated, so follow the instructions carefully. There is more information on the company’s website and even a few user-generated videos on YouTube.
Several other tools are available for working on this family of engines, some that provide speed and convenience, and some that make otherwise impossible repairs possible. Search the Product Guide on our Website (www.vehicleservicepros.com)