Appear to be in minority on this one, but I'd recommend changing O rings where internal water pipe connects to block. Mine were totally fried (about 25% original size and hard as a rock) -- not too many more miles before they leaked. Seem to remember James LaLonde had leak there too. If bolts that hold this pipe break, means they've been exposed to moisture already (leak?). I've always known process as "electrolysis" -- two dissimilar metals welding themselves together in the presence of moisture. If manifold mounting bolts didn't break, why should these? Are odd size (7mm), so if they do break be prepared to wait for mail order to come in before driving car. Bill Robertson #5939 >--- In dmcnews@xxxxxxxxxxxxxxx, id <ionicdesign@xxxx> wrote: > The water pipe under the intake with the 3 sensors on it should i leave it on when doing > a water pump change or should i take it off when i do the water pump change? > > Mark > 6683