Recent content by SeaDouble

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    1999 yamaha / mercury 4 stroke powerhead question

    I have a '99 yamaha F100 in need of a new powerhead. I found a great deal on a mercury 90 4 stroke powerhead, and I'm wondering if they are interchangeable. I know these engines are the same bore, stroke, displacement, carbs, made by yamaha, etc. But are they 100% interchangeable? Can I buy the...
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    Yamaha F100 problem

    I have a ?99 Yamaha F100 that I am recently having a problem with. The motor has unknown total hours, and has provided me approximately 1300 hours of fairly trouble-free service over the last 5 years Last trip out, as I was heading in across the bay I bumped it up from cruise up to 5000 RPM...
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    '99 F100 fuel issues?

    Hi guys, I have a '99 F100 that sat for a little over a year with gas in it before I recently bought it. I changed the oil, thermostat, and water pump, siphoned the old gas and changed the 10 micron h20 separator filter, then filled with 89 octane and a can of seafoam. Took her out this morning...
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    1999 yamaha F100 Water pump lower housing oil seal replacement

    Hi guys, I am replacing the entire water pump on my '99 F100 TLRX, including the lower housing and oil seals. My question is: Do I need to add oil to the bearing before putting the lower housing and oil seals back on? When I removed them some oil spilled out, but I'm not sure if this oil...
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    Yamaha F100 tilt/trim issue

    Hi all, Nice forum you have here. Thanks for all of the great info. I have recently bought a boat with a '99 Yamaha F100, and I am having an issue with the tilt/trim working intermittently. Sometimes it works normally, but usually if I trim up or down it will work for a few seconds, then stop...
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