2008 HPDI 250HP Series 2 overheating at idle

[briansgi]

At least I believe that's what it's doing. If I idle for 2-3 minutes I see my water temp gauge get to around 180. When I try and get it on plane a buzzer goes off and it appears to go into a safe mode and shuts down several cylinders is what it feels like, thus preventing the motor to rev up. So I turn off the motor, start it right back up, which I assume clears the computer, and I can then successfully get on plane and the temp immediately goes way down and stays down and I can run wide open throttle with zero issues.

I probably only have 25 or so hours on this motor and my water pressure since I bought the boat new has always read zero at idle and at WOT only around 12 PSI. I know different gauges can read differently but do you think it's time to replace the water pump rubber impeller and possibly replace the poppet valve too? I did have a little booboo a few months ago. I put muffs on the motor and tried to run motor in my drive way and it overheated but I immediately shut it down. Obviously my water hose and muffs wasn't sufficient in keeping the motor cool enough and maybe that is when the rubber impeller may have deformed and now is not working properly?

The motor is still under warranty, never done an impeller or the poppet valve so I'm reluctant to try this job myself, although I've seen the pics and video on the how to's. Any idea what my local Yamaha shop would/should charge for impeller and poppet valve replacement? Thanks guys!

[Rich Z]

About $100 per hr plus part but you don’t need new poppit just have it cleaned. The water pump impeller may be bad and you should replace it.

[09-20i]

I would start with the poppit valve, it's an easy job to clean. Mine and several of my friends all run around 24lbs at WOT.

I had to do mine after running thru a sand bar. Went from 24 down to 12. Cleaned it and right back up she went. If you are careful you don't have to replace the gasket so it's a cheap thing to check.

That low of hours I wouldn't think your impellar is toast.

I know our local shop charges ±$300 for a poppit valve job. I bet if you ask around one of your friends has done it once or twice and wwouldn't mind showing you how.

[briansgi]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by 09-20i &raquo;</td></tr><tr><td class="quote">I would start with the poppit valve, it's an easy job to clean. Mine and several of my friends all run around 24lbs at WOT.

I had to do mine after running thru a sand bar. Went from 24 down to 12. Cleaned it and right back up she went. If you are careful you don't have to replace the gasket so it's a cheap thing to check.

That low of hours I wouldn't think your impellar is toast.

I know our local shop charges ±$300 for a poppit valve job. I bet if you ask around one of your friends has done it once or twice and wwouldn't mind showing you how.</td></tr></table>

I'm thinking I might have "toasted" it though running it in the driveway on muffs and that's when it first over heated. Ever since then is when I've had this overheating at idle problem. Thanks for the input guys!

[09-20i]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by briansgi &raquo;</td></tr><tr><td class="quote">

I'm thinking I might have "toasted" it though running it in the driveway on muffs and that's when it first over heated. Ever since then is when I've had this overheating at idle problem. Thanks for the input guys! </td></tr></table>

Nowwwww you tell us not the end of the world. Hope you get her fixed up quick.

[Neilslure]

12 psi at WOT sounds awful low. In cooler water I see 20-30 psi consistantly. Your readings are what mine were when my poppit valve was clogged up. I had 300 hours on my impeller and still had good pressure when it was changed.

[chris c]

12psi is fine on these motors... If it was poppit valve, pressure will be even lower... I noticed my water pressure dropped to 6psi when valve needed cleaning.