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  1. R

    Shift Cable Jacket Looks Rusty

    My shift cable wouldn't shift, so I pulled off the outdrive. The shift cable's black outer sleeve is broken open in a 1" section of the cable between the transom and the "wall" that the outdrive attaches to. I can see rust inside. Is this rust just on the metal sleeve that the inner cable...
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    Fuel Pump has no Suction/Pressure

    I have a 1984 2.5L Mercruiser with an old-style mechanical fuel pump (bowl and filter on top of the pump) and no fuel is getting to the carb. I just replaced the filter inside the pump. If I disconnect the inlet fuel line to the pump, I feel no suction when the engine is cranked and my finger is...
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    Blew 110 AMP fuse. Pump resistance 2 ohms

    I blew the 110 amp fuse on my 1984, 120HP mercruiser with low pressure hydraulic trim pump. Solenoids seem ok--they operate when I disconnect wires to the pump. Resistance thru the pump voltage input wires to ground is 1.7 ohms. Is my pump gone? I don't see what else could pull that current in...
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    Lower Unit reattach-Last 1/4 inch stuck!

    I have an Alpha I, 1984 Merc outdrive. Replaced the impeller and trying to re-attach the lower unit. Boat is shifted full FWD, shift shaft is FWD and engaging the upper shoe. I rotated lower shift shaft CW to FWD and held it with the prop. It goes up in there, and by rotating the prop a bit...
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    3.7 140hp mercruiser

    The 140 and 470 are different engines. The 470 has a closed radiator system (like a car) and the 140 is cooled with lake water. There are several known issues with the 470, but once addressed it can be a good engine. However, I like the simpler 140 myself.
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    Shouldn't I have a PVC valve?

    1984 120HP. I noticed that the rubber tube going from the spark arrestor to the valve cover has a metal tube that attaches at the cover and looks like a PVC valve, but is just an empty tube. Shouldn't that be a PVC valve? What affects will not having the valve cause?
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    What model/YR car engine crosses to 1984 2.5L?

    Anyone know the GM car model and year that used the engine in my 1984 2.5L (153in3) 120hp in-line 4? SN is 6734398.
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    Will electronic Ignition fix Warm start problem?

    I seem to lose spark when starting the engine after it gets warm, and am thinking of converting to electronic ignition. Is that more reliable than doing a tune-up and staying with points? <br /><br />Would I have to replace the coil if I convert?
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    New Bearings, but feel Grinding When Not Tight

    I installed new bearings, but when I tighten the nut and turn the hub I can feel a grinding somewhere. The spindle has been scarred where the outer race mounts, but I sanded it so there are no protrusions. Any ideas as to what the problem is? After I loosen the nut the hub spins freely/smoothly...
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    Replace old 2-piece exhaust elbow with new 1-piece??

    This is a 120 Merc with the 2 piece exhaust riser/elbow on the manifold, 76325. I need to replace it, so can I use the new 1-piece version, 12076A2? Will the bellows mate properly with the old exhaust riser?
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    Rochester 2BBL vs. Mercruiser 2BBL on 120 4cyl

    I am trying to get rid of the infamous 120hp bog, and would buy a new or rebuilt carb if I knew it would fix it. Does ther Rochester do better than the merc? My bog is worse or better at various times. (Have a 1984, small diameter accel pump)
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    How to Get Exhaust Section Bolts Loose!

    1984 Alpha I, 120HP. I need to remove the bolts connecting 2 cast sections of my exhaust line-up and they are really stuck. I need to separate the lower section that has 3-bolt flange holding them together. I tried hitting the heads with a hammer and spraying with WD40. I usually resort to a...
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    Exhaust Flapper Fell off; Replace?

    I have a 1984 120HP Merc, alpha I outdrive. I heard a metallic clattering in the back where the water exhausts out one of the small holes on the side of the outdrive. Looking in, I see a small, thin stainless steel part about 1" wide. I think its the flapper that keeps water out of the exhaust...
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    Lower Unit off--shouldn't shaft turn?

    Have a 1984 alpha I. Dropped lower unit to change impeller. Trying to re-attach, but drive shaft spline needs to rotate a bit. I turn the shift shaft, but no matter where it is turned, the drive shaft won't rotate. Prop turns freely, as if in neutral. I thought I should be able to turn the drive...
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    120hp Mercarb-rebuild or replace?

    I have the famous bog and want to get rid of it. I can have it rebuilt for about $150 or get a new one for about $325. Cost to rebuild and evaluate/get boat running great is about $280. <br /><br />I heard this carb is a bad design and that even a new one might not fix the problem. Any advice...
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    How to manually lower outdrive?

    How do you manually lower the outdrive if the hydraulics fails? I see a knob on the pump, but turning it doesn't seem to do anything. Have a 120hp mercuiser.<br /><br />Thanks.
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    Battery main switch--GND or PWR?

    My boat has a main switch to disconnect the battery, and it switches the ground, not the 12V. Is this correct? Seems like it should switch power or there is power to the whole boat except for the last 12" of ground at the battery.
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    Will 170 carb fit on 120 engine?

    I have the infamous bog with my current carb on a merc 120, and am wondering if the carb on the 170 or 470 would fit since it doesn't seem to have the problem and looks almost identical. My rebuild instructions list the carb numbers as 1389-8490A for my 120, and 1389-8489A for the 470 (or 170...
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    Spark Advance Snap-back Check ?

    Have a 1984 120 Merc. When I rotate the rotor and let it snap back (to check the spark advance mechanism under the distributor) it snaps only most of the way back. It seems to not completely return to the original position. Is this OK? Engine has a surge at WOT only.
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    Accelerator pump adjustment question

    Have a 1984 Merc 120 with Mercarb. Just rebuilt carb and came to the adjustment of accel pump. The kit instructions say to measure from the top of the air horn to the top of the pump rod, but the Merc manual says to measure from the spark arrestor mounting surface to the pump rod. Both say the...
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