Do I have a "raw water system"???

[JT2Fast4U]

Hi. I'm very new to boating, & I was hoping someone could point me in the right direction to finding info on these types of cooling systems,(raw water systems) so that I can learn about these systems. Because my system doesn't "look" right, & my boat never really gets warmed up,it's always running cold & the temp gauge does work. Also, there are a couple of hoses on the cooling system that are plugged, & a fitting that goes thru the back of the boat that is not being used either. My boat is a 18'-6" 1973 Chapperal "run-a-bout",with a 455 inboard olds motor, with a Jacuzzi jet. Thanks in advance for info you can give me... JT2Fast4U

 

[cobra 3.0]

Re: Do I have a "raw water system"???

Does it have a radiator(s)? A closed system has. Raw water cooling system doesn't.

 

[JT2Fast4U]

Re: Do I have a "raw water system"???

No, it doesn't have a radiator.

 

[Bayrider]

Re: Do I have a "raw water system"???

Has the stat been removed.What diameter are the two plugged hoses,could they have been hooked up to a heater.The fitting going through the back of the boat could be for a bilge pump.

 

[Marlin455]

Re: Do I have a "raw water system"???

JT- I also have a 455 powered jet boat- the cooling water is pumped into the motor from the jet as follows- One hose from the Jet pump to a tee fitting- two hoses from tee fitting to rear of the exhaust logs(one hose each), then from the front of each log to the water pump plate on the front of the motor, then there should be two hoses on the top front of the intake manifold that run back to the exhaust risers, and dump all the water out the tips. It is normal for a jet boat to run cool- Mine never gets above 140 degrees no matter how hard I run it. Check out the forums at hotboat.com http://www.hotboat.com/forums/ for all the onfo on that boat you could ever ask for. The Olds 455 has some inherent oiling issues you should check out before you run it at above 4800 rpm for more than about 20 seconds at a time-If it will rev that high. Do a search on Hotboat for oiling mods, and cooling systems layouts. Stan

 

[JT2Fast4U]

Re: Do I have a "raw water system"???

First guys, let me say "Thanks", your input is very much appreciated. Thank You!!!<br /><br />Bayrider... the stat has been removed & the diameter of the hose in question is appx. 1/2"I.D. (there is only one hose that is plugged, I made a mistake in saying a couple of hoses, sorry.) I have two fittings that go thru the back of the boat, & one of them is hooked up to a bilge pump, & the other fitting is the plugged hose.<br /><br />Marlin455...Thanks for the explaination of the cooling system, now I have something to compare it to, & thanks for the link too. Looks like I have a WHOLE LOT of reading ahead of me. <br />Thanks again guys....JT2Fast4U