OX66 PH II

[ClarkBird]

Bit the bullet and added this pkg to the shopping cart this morning. Excited to see what this does for me.

[CJ1]

It is very noticeable. Midrange is stronger and 3 or so on top with my boat.

[ClarkBird]

Nice weekend project. Here's a look at the stock exhaust horn vs. Hydro-Tec. Couple items to button up and ready to make noise.

[J Risco]

Nice project, always good when you have a nice place to work on it too. Update with performance improvements please!

[ClarkBird]

Power band has moved up substantially. Doesn't jump on the pipe as quick as she used to but certainly feel more power. She sings at 5600. Didn't run her too hard as I'm burning off some lower octane fuel. Pegged it once and got 2mph over my best while still pulling and haven't hit the limiter yet. The new reeds made a huge impact, too. Idles smooth as silk with no more coughing and just sits there purring. Next step is to refuel with 93 and remind her who's boss.

[SCOTT196]

Let us know the top end increase!

[ClarkBird]

Since installing this kit I've been having some surging issues. Symptoms are - new plugs; run the boat and all is well. Stop to fish for a time and when I get back on plane I can feel the boat surging. Sometimes it will clean up and sometimes it won't. The first time it happened I pulled the plugs and while they didn't look dead, they were what I would call extremely wet with very little carbon build on the base of the body. Since this started I've replaced TPS, O2, adj throttle blades, lp pumps and had injectors serviced. Fished yesterday and on the way back to the ramp could barely pull 4k rpm. Compression still good (135-140 warm) so the mechanics are still there. Pulled plugs again and they look exactly as I described above. I always buy gas from the same station but moved up to 93 since installing the kit. Asked Matt about heat range on the plug and he said to run what Yamaha calls for. In this case - BR9HS-10s. I'm wondering if I need to run a hotter plug because it seems to me I'm just not burning the fuel and killing plugs. Checked spark with a spark-tester and while the arcs aren't "spectacular," there is spark. Tempted to throw a set of coils at it but at $400 I'd sure like it to be something else. Motor ran flawlessly until I installed these heads. Any input is appreciated.

[HaulinBass]

O2 sensor cleaning?
Time to convert from diaphragm fuel pumps to electric FP?

[ClarkBird]

O2 is new. Spoke to Wayne this morning and he suggested leaning out the oil pump and changing to a hotter plug. Will try those two things and see what happens.

[HaulinBass]

Keep us posted.

[harleyrs]

I have the Phase III kit with light weight flywheel with electric fuel pump, run 92 octane non etanol and switched to B8-HS-10 plugs and has been running great. Did you adjust your TPS to what Hydro Tech suggests?

[ClarkBird]

I have the Phase III kit with light weight flywheel with electric fuel pump, run 92 octane non etanol and switched to B8-HS-10 plugs and has been running great. Did you adjust your TPS to what Hydro Tech suggests?

Yes, TPS, throttle blades, oil pump all gone through and in spec. Also converted to electric pump. Will have first chance to run it tomorrow night. You're running B8HS-10s, not BR8HS-10? Same heat range with the only difference being the resistor.

[Montana Trapper]

My 225 ox66 would surge while running on step, 3 to 5 hundred rpm , checked coils ,grounds, & connectors. I was going to go over everything again , i touched the wire for the knock sensor & the sensor moved, checked the sensor, put it back in tightened in down, no more surging.

[ClarkBird]

Knock sensor is fuctioning properly. It has peaked my interest though to find out if the ecu is retarding timing for some reason. I see zero evidence of detonation on the plugs, they're just wet and black as night. Guess I'll get a winky-blinky and see if I can capture some codes running it.