You have to replace the intake manifold gaskets, which is not an easy job but if your mechanically inclined it shouldn't be a problem .disconnect the battery and i can not stress this enough, mark the distributors position to the engine block if not your computer will set a cam to crankshaft correlation trouble code.
We have had several 4.3L engines at work develop coolant leaks from the intake manifold gaskets failing.
if you can not see a leak!! check water pump,or intake gaskets,or a bad head gasket, GOOD-LUCK!!
Most often that indicates the presence of water or coolant in the combustion chambers. Common causes are head gasket leaks, intake gasket leaks, warped head/s or warped intake.
OHhhhhhh my. Where the are the good wrenches now? Have been driving a toyaota for the last 15 years, no water leaks here. Hope this helps.
The MOST COMMON PROBLEM with that engine is that the intake manifold gasket BLOWS / LEAKS water into the engine crankcase and mixes with the oil. Replace the intake gasket and FLUSH The engine oil and change the oil filter SEVERAL TIMES Untill engine cleans up.
when i turn my truck off water leaks from the bottom all the time
Drain the water from your Chevy Express cooling system. Remove the water pump return hose. Remove the water pump belt. Remove the water pump retaining bolts. Reverse the process to install the new water pump.
the temp of the intake manifold is controlled by the temp of the water in the block.
You have the infamous "Wet Carpet Syndrome". Check your cowl for leaks.
Drain the water from your 2003 Chevy Express 2500 cooling system. Remove the belt from the water pump. Remove the water return hose. Remove the water pump retaining bolts. Reverse the process to install the new water pump.
Right below the snout, there is a weap hold. When the bearing, and then seal, go south, this is where the water leaks.
It is in the middle between the intake and the water pump.