throttle responce adjusted?

Have you touched the cables lately?

Make sure you are getting WOT.

Second would be make sure its the correct sensor, and check timing.

Use a scanner to check for active codes that would limit rpms and power. sounds like a reduction to 90% power level on the Guradian protection?

Good Luck,
Ray @ Raylar

Quick question on the top end rebuild that everyone suggested....should the actaul valves themselves be replaced? Does this tend to be a weak spot for the 525 as well (the valves)? What about the piston rings? When is it a good time to swap those out?

New headers??

Yes, the CMIs will likely develop a leak sometime shortly after 300 hours.

it has always been told to me that the top ends should be gone through every 2-250 hrs, headers POSSIBLY around the 350 hour mark and complete rebuild around the 450 hr mark...sound bout correct ? OF COURSE IT ALL DEPENDS ON HOW ITS BEEN MAINTAINED, AND IN WHAT CONDITIONS ITS BEEN USED etc...

How hard do you run it? A fixed number of hours until rebuild without knowing how hard it is run and in what size boat is tough to call. A 525 in a Donzi 22 that runs 95% of its life under 3000rpm will live more than twice as long as one in a heavy 30 footer driven full blast all the time.

Thanks for all your help guys. I ended up rebuilding my engine and it runs like a charm. I thought it was a wiser way to spend money. Unfortunately, I have to sell her now, so if anyone knows someone interested, please send them my way.

You guys were right on about everything. Hopefully, other people that have 525's will do the smartest thing as time goes on.

Thanks,

Ron

Another question...does it matter what type of coolant I use? I'm just looking to top off what is in there already.

Was told that I shouldn't use green colored coolant...?