5.0 Gi PWTR Engine No.4110178758
Salt water used for 6 or 7 months a year from new (1999)
Overheating at idle,
I have installed clear hoses T'stat to -> manifold and have no supply at idle, but stuttering supply at 2000 rpm (increasing with revs). Engine pulls really well and WOT is 4900 rpm.
Tests
Clear hoses on suction and discharge of raw water pump, no sign of air (but difficult to see clearly)
Removed outdrive plastic nipple (not cracked) and pressure tested hose from there through transom to outlet of power steering pump oil cooler, it held 30 psi for 10 mins.
Pressure tested raw water pump to 30 psi and vacuum tested it to 25 inHg held both (rotated pump to make sure).
Replaced
Raw water pump impeller (VP)
Raw water pump body (VP)
Raw water pump new seal and Bearing last season.
New T'stat housing and T'stat last season 160 F. Boat will run at anything over 2000 rpm all day at 160 F.
Manifold and Risers are 4 years old.
I'm starting to think I might need to do a compression test, although with 33 C (92 F) and 80% humidity here in Spain I am not looking forward to that or the consequences.
I have run out ideas, anybody else got ant ideas??
Salt water used for 6 or 7 months a year from new (1999)
Overheating at idle,
I have installed clear hoses T'stat to -> manifold and have no supply at idle, but stuttering supply at 2000 rpm (increasing with revs). Engine pulls really well and WOT is 4900 rpm.
Tests
Clear hoses on suction and discharge of raw water pump, no sign of air (but difficult to see clearly)
Removed outdrive plastic nipple (not cracked) and pressure tested hose from there through transom to outlet of power steering pump oil cooler, it held 30 psi for 10 mins.
Pressure tested raw water pump to 30 psi and vacuum tested it to 25 inHg held both (rotated pump to make sure).
Replaced
Raw water pump impeller (VP)
Raw water pump body (VP)
Raw water pump new seal and Bearing last season.
New T'stat housing and T'stat last season 160 F. Boat will run at anything over 2000 rpm all day at 160 F.
Manifold and Risers are 4 years old.
I'm starting to think I might need to do a compression test, although with 33 C (92 F) and 80% humidity here in Spain I am not looking forward to that or the consequences.
I have run out ideas, anybody else got ant ideas??