I want to pull my sensor and can't remember if the KS threads go into the cooling system. It is about the same location as the old "drain" plugs on the side of the block but it seems I remember the KS threads were a blind hole.

IOW if I pull the KS will the coolant come out on a stock l98 block? Anyone know?

 

I replaced mine on my 88. Coolant started pouring out the second I removed it-lol

 

The coolant may or may not pour out. I've removed them from older engines where enough debris built up in the bottom of the block that either no coolant came out or it just dripped.

If it is a newer build, what IROCThe5.7L said.

RBob.

 

Every GM knock sensor I pulled was in coolant, whether it leaks or not is an indication of clean cooling system. LT1 engines are notoriuos for being plugged and removing knock sensors is a way of getting crud out of bottom...

Are their any knock sensors not in water jackets? I thought that was inheriant to there design?

 

Yep, it was in the cooling system. I took a shortcut and creaded a negative pressure in the cooling system while I removed the sensor. It worked to a point but I still took a bath lol. I added a 45* brass elbow to desensitize the sensor as described by Grumpy (RIP). Seem to have helped without making it usless.

 

NorthStar engines have it in the lifter valley under the intake manifold. The Turbo Buick engines have it located on the top rear of block on the bell housing mount area. I've seen some 4.3l engines (in Astro vans) with it also located there.

RBob.