rooferdave
Cadet
- Joined
- Jun 10, 2010
- Messages
- 7
It is a 1988 raw water cooled 5.7, it runs at 185 and after 1900 rpm climbs to 200-210 and cools back to 180-85 when I throttle back. First off I changed impeller and housing also confirmed that the t-stat was correct one (140) and replaced. IR gun gave port riser at 94 degrees and starboard at 148 deg, clear tubes to upper and lower riser showed bubbles (slight into top, many in bottom although hose did not appear to be full of water) I have twin engines so I took riser/manifold from cool engine and swapped, still the same. pulled head and had it magnafluxed... no crack found and shop thought head gasket was leaking. Re-installed last night and still the same 
. Also I thought maybe the check ball was not allowing water to pass but clear hose shows it is opening and allowing water through. I have also back flushed the engine in case of old impeller parts etc, I have removed all hoses inspected and flushed them, new hose from seacock to impeller pump (old one was not reinforced) inspected seacock for blockage and flow, thinking that the waterpump is the only thing left ...except for the port head. Also the transmission cooler was pulled and is clear
Any thoughts all?
Dave
Bouy oh bouy this is my first boat and I have yet to take the family out in it! What an introduction![/QUOTE]
. Also I thought maybe the check ball was not allowing water to pass but clear hose shows it is opening and allowing water through. I have also back flushed the engine in case of old impeller parts etc, I have removed all hoses inspected and flushed them, new hose from seacock to impeller pump (old one was not reinforced) inspected seacock for blockage and flow, thinking that the waterpump is the only thing left ...except for the port head. Also the transmission cooler was pulled and is clearAny thoughts all?
Dave
Bouy oh bouy this is my first boat and I have yet to take the family out in it! What an introduction![/QUOTE]
