hey guys,

i'm going to restore the inner thread of my oil-pressure switch inside the block this weekend.

bought the 1/8 x 27 npt tap last week ...hope this will do it.

any suggestions or tips? i'm afraid that after tapering it, the new switch won't fit tight enough.

the problem is, when i'm tryin to get the switch back in the block..only 1,5 or 2 turns are possible..then it stops..its also hard to get a straight alignment....the thread of my old switch got only 2 or 3 threads left..the lower end was kinda worn and blank...the new one looked the same after i tried to get it in.

 

it'll work, just run the tap in a little at a time and use a good cutting oil and you should be fine. worst case scenario you'll have to drill it oversized and bush it... not the end of the world...

 

Put heavy grease in the hole so chips won't get into the oil passage. Clean out as well a you can to remove most chips after tapping the hole just the minimum needed. You can disconnect the coil and crank the engine to blow the grease out afterwards. You will get a mess unless you loosely cover the hole area with a rag.