Safe PSI 250 sho?

[GEEBASS2000]

Can't find it in my Owners book, but do any of you guys know the min psi for a 250 SHO??? I want to go up on my jack plate but don't want to buy a new outboard.

[Stratos21XL]

No less than 18 PSI at WOT.

[berger1b]

This is copied straight from the FAQ's page on the Yamaha site for whatever it is worth.

What is the minimum water pressure required for my Yamaha outboard(s)?

All Yamaha outboards have a minimum water pressure of eleven (11) psi at Wide Open Throttle (WOT). There are no announced water pressure specs for low or mid-range operation at this time. This is due to our high volume low pressure cooling system design. In fact, you may see zero pressure at idle, as most water pressure sensors start working at 3-psi.

[Stratos21XL]

interesting. I have always been told 15 to 18 psi minimum by dealers depending on which motor it was. Not doubting what they are saying or what you posted at all but 11 PSI at WOT seems terribly low to me. Wouldn't be the first time a dealer has given me the wrong info.

[falcooon]

The SHO is different... for instance there is no poppet valve in the cooling circuit.

I would note whatever reading you have and look for significant differences as time goes by. The SHO measures temperature in many places. If it over heats it will let you know...

[berger1b]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by Stratos21XL &raquo;</td></tr><tr><td class="quote">interesting. I have always been told 15 to 18 psi minimum by dealers depending on which motor it was. Not doubting what they are saying or what you posted at all but 11 PSI at WOT seems terribly low to me. Wouldn't be the first time a dealer has given me the wrong info. </td></tr></table>

I too have been told by a lot of people to keep mine at 15 psi or above. I have always run between 15 and 17 psi at wot. That is why I said "for what it's worth". Yamaha leave's a lot to the imagination. But I think Les has got the right idea and makes the most sense.

[GEEBASS2000]

Thank you all for your time and info!!!!