I want to thank everyone for the replies and the comments trying to rectify this problem. As stated, I have had this issue since new and the boat is now 10 years old. I was told by the marine place that sold me the boat new that there was no issue with heating and that they had actually replaced the water pum, ( at a cost of $500, 'Warranty?, the water pump doesn't fall under warranty'
Well last weekend, being 29th April, 2014, I chose to buy a water pump, impella kit, and replaced the water pump and housing myself. To my dismay, and disgust, I found the bottom gasket of the water pump housing, had a tear in it. It was therefore replaced and after water testing that day, the temperature gauge did not get above 1/4 warm. All this time, a $3 gasket was the reason for this temp issue. I was not able to use this boat for its intended purpose because I believed what I was told by the marine place that sold me the boat and motor.
They are yet to hear from me about this as my anger has yet to calm. They will hear from me in the coming weeks. I wish I could name and shame this place but am not able to as I don't wish for repercussions from this site.
In this time, I had lost interest in using the boat, taking my family out in it, and after consulting with mechanic authorised to Solve this issue, was not able to for fear of the unknown costs involved.
I have a renewed passion for fishing, have taken my youngest son last week into Botany, and have has the pleasure of seeing him hooked up to decent sized Kingfish on several occasions. We are about to join the local fishing club in Sans Souci and plan on making up for lost time.
Thanks again all who took the time to try to help..
Regards
Wes