Recent content by bheston

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    How does guardian mode work?

    I'm helping a friend with his 2014 Mercury 115hp EFI 4 stroke. We had a couple issues that we now have resolved, but engine acts like it's running at half power. When on the hose in the driveway, in fast idle the engine runs fine up to around 2000 rpm, then falls on it's face and won't go above...
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    2014 mercury 115hp EFI 4 stroke running rough, lack of power

    I don't know about adjustable rocker arms, how can I tell? I'm helping a friend with this boat, I put the spark plugs in last year. Bought the same replacements that I believe are spec'd for this engine which are NGK LFR4A-E. I'm going to put those in next and test it. Does anyone know specs...
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    2014 mercury 115hp EFI 4 stroke running rough, lack of power

    I've been troubleshooting issues with this engine, and found a problem with the low pressure fuel pump and have that fixed. On my test run the engine now has consistent supply of fuel, but is running very rough above 2000 rpm, and barely has enough power to get the boat on plane. At wide open...
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    Troubleshooting Mercury 3075-28 Electric lift fuel pump issue

    Has anyone bench tested a low pressure pump? Does it run on 12v?
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    Troubleshooting Mercury 3075-28 Electric lift fuel pump issue

    I'm looking for advice to troubleshoot a 2014 mercury 115hp EFI 4 stroke. After a problem with a water pump replacement, the engine got hot. Water pump problem is now fixed and pumping water as it should. Then engine appears to be in guardian mode, limited to 2500 rpm. I bought a SmartCraft...
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    1969 Mercury developed a miss or "coughing" when running

    I have a 1969 Mercury 7.5HP outboard that has only been run a couple times a year for the past few years, it has developed what I call a cough, where the engine will miss and it sounds like a cough, there is actually air that comes out around the fuel pump when this happens. It does this at all...
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    Motor RPM and prop size on 24' pontoon

    Hello, I have a 1984 24' Aqua Patio pontoon with a 50 HP Mercury outboard. The prop that is on it is a Quicksilver stainless steel 3 blade, 48, 76228, A5, 13P. When I open the motor up the boat picks up speed for about 5 seconds, then I hear the motor sound change, it sounds like the motor...
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    1985 50 HP Merc, NO SPARK, what am I missing??

    1985 Mercury 50HP 4 cyl, SN 6587637. Out on the lake a few weeks ago and went to start the motor, fired then quickly died, no spark from that point on. Did some testing and found the stator was bad (ohm reading on low speed side way out of range) so bought a new one, installed it and still no...
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    1985 50 HP Mercury won't pump water, does this motor have thermostat?

    After lots of searching I can't find the answer to my question, so I'll start a new thread. Fired up my 1985 Merc 50 hp with the garden hose muffs for the first time this year and won't pump any water. SN 6587637, 4 cyl. I can blow compressed air from inlet to outlet and outlet to inlet, and...
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    Evinrude 48HP can't find model or SN

    I bought a pontoon with an Evinrude 48 hp on it, I need a few parts and can't seem to find the model or SN on this engine. I believe the motor to be a mid-1980s, can anyone tell me where these numbers are usually located? There is one place on the transom bracket that looks like it may have...
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    Removing gimbal bearing

    1989 OMC cobra 4.3L, I got into the gimbal bearing and am not sure how to remove it. I have read through the posts I can find and some use a slide hammer and others a puller, what works best? My manual tells me to use a puller, my puller doesn't fit into the bearing. One document shows the...
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    New boat has bad vibration when running

    I just purchased a 1989 Four Winns with a 4.3L OMC cobra. I ran it on a hose before I bought it and engine runs great, shifted fine, ran quiet in gear. However once I got it in the water, it has a pretty loud vibration in it, even in neutral. The whole hull of the boat is shaking. It gets...
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    Filling lower unit oil

    I have a 3.0L OMC and changed the lower unit oil. Everyone says to fill from the bottom, which I assume they mean the drain plug. So the lower unit has a drain plug clear on the bottom, fill hole around the middle side of the unit (towards the top of the lower half of the unit that is) and the...
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    Removing lower prop shaft from OMC cobra

    I am removing the lower shaft from an OMC Cobra 3.0L to inspect the dog clutch and gears. I have a service manual on order but wanted to get some real world feedback on this process before I started. I have the outdrive removed from the transom bracket. Looking at the lower shaft it appears...
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    OMC won't shift into forward gear

    I have an OMC outdrive on a 1987 Bayliner, 3.0L engine. I bought the boat knowing the lower unit has problems but don't have any more information. I put it in the water and it will shift into reverse and seems to run fine, unit is quiet and goes in and out of gear good. When I shift to...
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