Recent content by scjmc

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    1997 Yamaha 0x66 250 power issue 4300 RPM max

    I am having an issue with my motor SX250TURV that I need some direction on. I have read many posts before posting this, but I feel that I need some more help. Motor has run almost problem free for the last 3 years. I stay on top of maintenance. Friday before last went out and the motor ran...
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    1997 0x66 SX250TURV only running on 5 cylinders coil ruled out..

    So I figured out that my engine is only running on 5 cylinders. My cylinder #3 is not firing. No spark... I conducted tests above 2K RPM (I know that it runs on 4 or 5 cylinders at lower RPMs but I am not sure which ones). I swapped coils between #3 and #5 and the problem does not follow the...
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    Outer exhaust cover question 1997 SX250TURV

    I am trying to remove the outer exhaust cover located behind the CDI. There are 25 bolts, and I broke the 4 in the middle of the cover. The other 21 are ok. The cover is stuck on because the 4 center bolts that broke (whats left of the studs) are siezed to the cover. I have tried to...
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    Should I replace main bolts that hold motor to motor bracket?

    I recently pulled my powerhead because of a water leak that I had between it and the midsection. It looks like it was just the gasket that needed replaceing. Another problem I found was the main bolts that hold the engine to the engine bracket on the transom. The bolt heads are only visable...
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    Water leak between block and midsection?

    I have an S250TURV and have developed a water leak!! I am leaking water from what apears to be the forward part of the powerhead between the powerhead and midsection. There is a seal there (looks like a 1/8 inch rubber gasket and water is coming out from underneath it.) I do not see any water...
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    Is my o2 sensor OK? 1997 250HP SWSII

    I was wondering if I hurt my O2 sensor. I took it off and soaked it in ringfree for 5 days. I only soaked it to the bottom of the threads. I have been waiting on some back ordered parts including the gasket to reinstall the sensor, so I took it out of the ringfree and rinsed it with gas. Is...
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    Yamaha Ox66 using way to much oil!

    My 1999 Yamaha ox66 250 is using oil at about a 25 to 1 ratio. I do know what is causing this. I have adjusted the oil link rod to specification, and it moves freely. I have checked the bilge and cowling for leaking oil and I have found none. Does anybody have any ideas? I guess it could be...
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    Ideas on powerhead failure? Yamaha 150

    I took apart my failed powerhead today. I found cylinder 4 (I think 4 its the port side middle hole) dry of oil. The connecting rod to crank bearing was melted and that portion of the crank was rusted and looked ike it got very hot. There was a small piece of the piston skit broken off...
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    Yamaha 150 Carbed Powerhead Interchange Question

    Pulling my powerhead Saturday. I expect a thrown rod, so I am considering buying a rebuilt powerhead. Does anyone know what year 150 carbed powerheads interchance from? There is a guy selling one that he says fits 93 up 150 carbed motors and I was wondering if it would work. Thanks...
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    Pulling Power Head on Saturday!! Yamaha 150

    Wish me luck everybody. I will be pulling the powerhead off of my 99 Yamaha 150 carbed motor. I will then dismantle to determine failure. It will turn by hand easily, but only about 3/4 of a rotation then it stops abruptly. I suspect it threw a rod. I have a good comprehensive manual that I...
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    Yamaha 0X66 Paint Code

    Does anyone know the paint code for an 0X66 motor? I am assuming they are all the same color, but if not mine is a S250TURV. On http://www.colorrite.com/ they have 2 colors that dont list an application--codes 004D, and 008D. Anybody know? I have someone that mixes paint for me, and I was...
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    TPS readings all wrong!! Help with TPS please... Solved!

    I was following the procedures for link and sync with my 1997 250HP 3.1L OX66. When I got to the TPS I had voltage readings of 4.8 volts. Thats right 10 times the .48 volts my manual said to look for. I know how to read a volt meter and I was reading 4.8 volts. I even grapped a second meter...
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    OX66 stals at high RPM!!!

    My 97 OX66 250 is stalling at speed. It seems to stall when fuel consumption is high. It will go from a cruise 4000+rpm to stall in about 3 seconds.....but sometimes the rpm jumps around and gradually falls. The engine mounted fuel filter stays about 80% full while running. The engine still...
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    Raw washdown/baitwell question

    I have a seperate pump for my raw washdown, and baitwell. When I hit either switch I can hear the pump running, even put my hand on it and feel the vibration. I dont get any water out of either. When I am running I get water flowing out of the washdown hose, and into the baitwell, so I dont...
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    VST filter question 250 OX66

    Hello all. I have been reading on this site for some time, but now I need to ask your advice! I have a 1997 Yam 00x66 250. This weekend it intermittently (did it twice) lost power and the RPMs backed down. If I reduced the throttle, they would come back up. Only shutting off the engine and...
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