I set my boat up a couple years ago with this system and my dad helped me set the valve to a certain psi.. He actualy passed away a lil over a year ago.. I rebuilt the motor this winter and im now installing everytyhing and i wanna double check to see that the valve is still set to the right pressure to open .... So my question is. what should the relief valve be set at to open at? and what would i use to set the valve? Thanks for ur time 

I have mine set to open up at 12 psi but im running an olds block and they are the weakest when it comes to pressure. This setting was recommended and set for my by james from performancejet.com Any other motor can handle a bit more but I'd guesstimate 15-20 should be fine.

Right in line with everyones thought there! But I'm gonna throw my .02 in because of the expensive engine I trashed last year due to severe water reversion.

Thing to remember is, Olds, BBC, BBF, Mopar, I don't care what, are street engines, and thus, pretty easy to convert the 15lb or 18lb popoff radiator caps we used to run on them in the day to what we think of on these boats. I know...."they've been running for years this way", but the sheer number of failures last year and durability history of jet boats in general caused me to really think about why mine went down so hard.

Understand that is STEAM pressure, not WATER pressure.........Water cannot be compressed, whereas steam can (hows the old locomotives work???) Cars run at 195* or so, near the 212* water boiling point in the open atmosphere (More like 230* or so in a closed cooling system) whereas our boats run anywhere from 120* to 160* in open cooling systems. There IS a difference in Marine gaskets, to be sure, for this very reason, but on the water pressure side, I'm gonna shoot for like 8 PSI from this point forward...........

Ray

to also help against over pressure I run both of my t stat lines overboard, two lines in two lines out, I have a 90 coming off another port on my intake manifold to my basset t for my headers. Pressure is not as important as volume, so running even as low as 8 couldn't hurt, from what I figure.

THAT is what my long ways about response was all about..........Just make sure, if you're running headers, you have a way to un wet them at or near idle, manually or otherwise..........Hydraulic pressure is in no way, shape or form, comparable to gaseous pressure. There is an important difference. The boat engines of yesteryear got away with it with top (VERY INFLATED) HP ratings of 330 and maybe 400 or so. We're way beyond that, realistically. 

Ray

Ray, do you think the basset T valve is enough to cover the headers or so I put a rexmarine manual switch on there as well. Like many others I'm afraid about forgetting to turn it on or off and I've heard of a ton of people having problems with the banderlog valves?