Sealey Ms003 Reverse Action Spark Plug Thread Chaser 14Mm

Great thing for what it’s made for saved me a lot of money and time

Having damaged the outer 1/3 of the head on my outboard engine, this tool easily inserted and fixed the thread, bringing all the swarf outwards with it.

Man schneidet von innen. Dadurch setzt der Sealey am gesunden Gewinde an und überschneidet sodann das beschädigte Gewinde. Ich habe es zweimal hintereinander geschnitten. Danach konnte ich die Zündkerze wieder normal eindrehen. Gut einfetten.

Excellent tool... I have an old Nissan Bluebird with an alloy head. The threads on the spark plug hole were damaged. I couldn’t get the plug in without it cross threading. After running this through once I installed the plug no problems. Access to get to the hex nut on top of the tool was very tight, so I chopped my spanner in half which made it do-able. Saved me pulling the head off to get it helicoiled. Well worth the money.

After the first few threads of my motorcycle spark plug started to go awry, I searched for answers online to avoid removing the head (again). This little tool looked just the business.I did as others advised and put some grease on the business end of the tool before inserting into the plug hole (with the engine piston at the bottom of its travel) and began to open the threads. This was when I experienced a problem. The threaded retraction lever wouldn't pull back any more as I turned it after it started to engage the plug threads. This meant that the cutting threads were not being pushed into the plug thread hard enough to chase the damaged threads back to their correct position. The (necessary) grease was allowing the central expander rod to spin as I tried to tighten the tool.The solution was to restrain the central rod from turned as I tightened the tool. I used a metal saw to cut a line in the top of the rod (see image) and this allowed me to insert a flat screwdriver inside, restraining the central rod while I turned the outer tool with a spanner - this worked a treat, pulling the thread cutter to full expansion and allowing me to finish the job. 4 stars as the fix I made should be standard.