7/8" Mega-Bushing Installation Suggestions

This bushing has oil on it. It will need to be thoroughly cleaned before installing.

Drill the blown hole to 49/64 for a 7/8 tap.
(A 3'4" hole is just 15 thousanths smaller than 41/64", and will probably work ok, tapping into an anluminum head. Go Slow!)

Tap the blown hole to 7/8-9. A tapered tap will start easier than a plug tap, but either will work.
Cover the tap with wheel bearing grease to stick as many metal chips as possible.

Use a 12-point socket on the head of the tap. You will not be able to use a tap handle.

After tapping the spark plug hole, unhook the ignition and crank the engine a few rounds to blow any chips that fell in the cylinder. Or, use a small adapter on a shop-vac.

Clean and dry the new threads, and the bushing thoroughly.

Screw your NEW spark plug into the adapter.
( the torque for this plug is 7-14 ft-lbs or 84-168 in-lbs )

Apply JB-Weld to the external adapter threads, (NOT to the spark plug threreads) and screw it into the hole and tighten with a spark plug socket.

Let the JB-weld cure for 24 hours before starting your engine.

NOTE: JB-Weld also has a quick-set formula which can cut the waiting time down to a few hours.

Good luck with your repair!

This sheet is also online at gartsworld.com