Recent content by FredM

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    No power from bottom cylinder

    Hi all,<br /><br />I have an '81 model merc 18hp two cylinder single carb. SN 59118844<br />Cruising along nicely and suddenly dropped revs.<br />Top cylinder runs fine. Have good spark, changed plugs, compression good - 145psi on both.<br /><br />With the motor running, I ground the lower HT...
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    Head temp difference

    I have a 2 cylinder '81 18hp merc. While doing maintenance I noticed that the top cylinder head (integral type) runs significantly hotter to the touch than the lower one. I can hold my finger on the top one for a couple of seconds but the lower one I could hold all day. The tell tale only...
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    Small hoses on Merc - What are they?

    Hi all,<br /><br />I have a 1981 Merc 18hp 2 cylinder. It has a single carb with integral fuel pump.<br /><br />There are two black flexible tubes or hoses about 1/4" dia, each running from near the transfer port covers of each cylinder back to somewhere under the carb (can't see where they are...
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    Mercury Chrome Bore any special care needed?

    I have a 1981 18hp merc with chrome bores. It's running fine and has good compression but would like to know if there is anything else apart from the usual maintenance that should be done, or to watch out for? <br /><br />Being chrome is there a stronger argument for or against decarbing?<br...
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    Merc Timing

    Just checked the timing (at cranking speed) on my '81 Merc 18. Timing light shows about 4 deg too advanced at WOT (29/30 BTDC instead of 25 - 3 punch mark on flywheel). <br /><br />Trouble is the trigger linkage is as short as it will go and I need to shorten it to retard the timing. Is there...
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    WOT Timing Merc 18 breakerless CD ignition.

    I read with interest a post (xyphrx on 12 May 2003) where Gold Bear explained to how to set WOT timing out of the water by cranking the engine briefly with empty carbs and the throttle set to WO.<br /><br />I want to check the timing on my Merc 18 electric start (I have a manual for doing in a...
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    Bent prop shaft

    I hit a submerged object and bent my prop shaft about .019" (19 Thousands of an inch). I have managed to straighten it to within .009" which can't be seen with the naked eye when rotating the prop by hand. Is it worth trying to have it straightened anymore or should I just leave it to overhaul...
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