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    90HP Inline 6 (tower of power) carb rebuild - what size jet?

    I am looking to rebuild my carb's on my 1985/1986 Mercury 90HP inline 6. 1) Serial number OA968445 which has always confused me as part list don't usually have letters in front of them (assuming I would fall in the last category below ("8071020 and up)? 90 (6 CYL.) - 5299506 THRU 5594656 90 (6...
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    90hp Mercury -idles perfectly at 650 rpm, occasionaly idles up to 1200 - Stuck float?

    I have a 1986 mercury tower or power, 90 hp inline six. I have it tuned to idle at around 650 rpm's which is just about perfect from what I can tell. I will sometimes run the boat for part of the day, and sometimes (doesn't always happen) the rpm at idle goes up to about 1200. I am planning on...
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    Temp sender help! 1986 Mercury, 90hp inline 6

    I own the following engine: MERCURY - ( 90 H.P. (1986 )) Serial No: 0A968445 Model No: 1090726 After some overheating issues last year (which I believe have been solved by rebuilding the carbs and other repairs), I am attempting to install a temp gauge AND a water pressure gauge. My engine...
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    1986 Mercury 90hp Help with Temp Sender / overheat

    I am in the process of fixing up my 90hp 1986 mercury Tower of Power, serial # 0A968445, model 1090726. I had an issue with a cylinder overheating in the past, but still have good compression. I was running it on 5 out of 6 cylinders, but now after replacing switch packs have spark on all 6...
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    Is a 1986 Mercury controls interchangeable with a 1990 Mercury

    I have been having problem with my 1986 Mercury Tower of Power, 90hp and have come across a 1990 mercury 90hp for pretty cheap. Does anyone know if I can swap the newer engine for the older one without having to buy new controls etc> Any help is greatly appreciated.
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    No Spark on Odd Cylinders, Switch box Help - 90hp inline 6

    I own a 1986 Mercury Inline 6, I had an overheat in the #3 cylinder and that cylinder stopped firing. After that the engine ran on 5 cylinders for a while, then dropped another cylinder (I think #1 but dont remember). As I was working on the boat to repair the dropped cylinders (which I thought...
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    Fried Cylinder - inside view with high 10x magnification

    I was driving my boat when day when it my Mercury 90 HP Inline six "tower of power" started smoking, got towed in and took the spark plugs out - found one plug from the #3 cylinder had melted aluminum, a sure sign of an overheat. I still am not sure what caused the overheat and that is what I am...
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    Running on 5 out of 6 cylinders? 90 hp inline 6

    I had a problem recently with my engine which caused my #3 cylinder to overheat (causing melted aluminum on inside of cylinder and on the sparkplug). I am not getting spark to that cylinder and while I am troubleshooting the cause of overheating (maybe running to lean? Bad water pump?) I am...
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    Smoke from engine, one badly fouled spark plug, and water leaking from all all plugs

    Hi all, I want to thank you in advance for reading this- this is a great community. I have a 1986, MERCURY - ( 90 H.P. (1986 )) Serial No: 0A968445 Model No: 1090726 I was driving home the other day when the engine made started smoking so I cut the engine right away. Even after...
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    Mercury 90HP-1985 Tower of Power How to install new rectifier -old one is different

    I have a 90 hp mercury tower of power, year 1985. I have been having issues charging and after reading the forums decided to try swapping out the rectifier since it is cheap and the most likely problem. The new rectifier looks like a standard three terminal (with the metal frame on the back...
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