Honda Car Forum

...Carburated Engine? I need to rethread one of the spark plug sockets and need to know what size of rethread tap I should purchase? Please answer only if you know the exact specific technical answer. Guesses are not needed.

What you're actually "technically" trying to do is to rethread the hole in the cylinder head where the spark plug goes. "Technically," a "spark plug socket" is what you use to remove a spark plug. What you should do is take it to someone who "technically" knows what they are doing.If you insist on doing this yourself, go to an auto parts store--they should have a spark-plug rethreading kit.

14mm

I just repaired one spark plug hole in the head of my '90 Honda Prelude and it went perfectly... here's exactly what I did:Go to Autozone or equivalent and rent/buy a spark plug hole repair kit. The kit is made for 14mmx1.25 spark plugs and comes with a small variety of different LENGTH inserts so you can match the length of your spark plug threads with the insert you will be using.Unless the head is off the engine you will need to take EXTREME measures to ensure the metal chips coming off the reamer/rethreading tool do not fall into the combustion chamber! Do this by rotating the engine until that cylinder's exhaust valve(s) are open to the exhaust pipe. Insert an air compressor hose into the exhaust pipe (you can probably use a shopvac in blower mode or maybe even a leaf blower, i.e. be creative.) You must establish air flow coming out of the spark plug hole you are fixing to blow the chips out instead of letting them fall into the chamber.Then, just use the kit as instructed... cut the new threads for the insert, clean any debris created by cutting, install the insert with hi-temp sealant, and set it permanently with the tool in the kit. That's it... all done!Worked like a charm for me and the kit was cheap enough too. Sure beats replacing the head!Good luck!