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Mercury 4 stroke outboard running rough?
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Mercury 4 stroke outboard running rough?
Also checked the spark, firing on all 4 cyl's. It has run fine since new. anyway cut a long story short after checking thermostat impeller etc my issue was the rubber grommet below the power head on the adaptor plate. Also at high Rpms (5000), the alarm beeps 6 times once after running for about 30 mins Mechanic's Assistant: Sometimes boat issues seem like they'll be really complicated, but end up being easy to fix. My motor run great from idle to wot for about 10-15 minutes, then starts cutting out. I run it for a while and then get an alarm. It started this crazy idling/stalling issue just ---coincidentally after i topped the boat tank off with gasoline. In this video I'll go over some of the fuel. Jan 11, 2013 Re: 09 mercury 60hp 4stroke running rough at low rpm. Messages Mar 27, 2012 Re: Mercury (Classic) 40 hp loses power on full throttle. Vocational, Technical or Trade Scho. High idles are caused primarily by too much air entering the engine after the intake. After pulling the kids on a tube for a while and getting up to 5500 rpm we slowed down and stopped and swam for a while. While Mercury is widely known for building top-quality outboard engines, it can be assumed that some users can … Mercury 90 HP 4 Stroke Problems: Troubleshooting. For the month of july i did numerous short runs of a kilometer or less to local fishing holes and motor started fine each time I used it (turn key to on, fuel pumps runs for ~4 seconds and stops, turn key to start and motor starts easy after a second or two with no throttle required. By Joe McElroy. Coming out of Marina, when I get out of no wake zone and give it some throttle, it gets up on plane no problem and runs great By addressing these common Mercury 9. almost like a loss of fuel. Find out how to fix a rough running lawn mower engine by adjusting the spark plug gap, cleaning air and fuel filters, and switching to ethanol-free gas. the grinding is the clutch dogs skipping across each other. My manual says to check and replace (if necessary) low pressure fuel filter every 100 hours or yearly, and to check and replace high pressure in-line fuel filter every 300 hours. Everything from electrical and phone lines to cable and speaker wires need to be roughed. Deliveroops. I have a 2014 Merc 9. but it runs perfect after that. It will even hesitate and stutter a bit just before the other two chime in at 2000 rpm. Spring is well underway and we are about to roll into. Aug 15, 2016 I have a 2014 Mercury 60 hp 4 stroke efi. There is no tracker valve on the 115. the cause was corrosion was squeazing the grommet and restricting. I need help troubleshooting a problem and I need answers to a few questions9HP mercury won't accelerate. I have read all the rough idle posts and still have a question. The coils of some mercury outboards are sealed inside a unit with oil. Apr 24, 2014 · I have a 2014 Merc 9. The Mercury 150 Four-Stroke outboard was introduced in 2011, to much fanfare. In a nutshell, when I power my engine over 4900 RPMs, I frequently hear the infamous 6 beeps from the. However, there's one more thing you can do to troubleshoot an outboard that runs poorly at idle: Clean the Carburetor. Tweet Yamaha 25 hp 4 stroke runs rough when warmed up. Oct 8, 2003 · Messages Oct 8, 2003 My 2001 90 hp 4 stroke will rough idle after start up. Old or contaminated fuel can cause engine performance. We bought a 20' Bennington SLX Tritoon with a Mercury 115 HP Four Stroke motor new in 2017. The 4-stroke outboard engines, in particular, provide boaters with dependable power, smooth operation, and excellent fuel efficiency. Now for the fix: I pulled the carburetor and took. 10 #7. The Classic Convertible Mercury Cars Channel lets you see under the hood of Mercury convertibles. Check the Oil Level or Fill the Oil Injection Tank. 2002 75hp mercury 4stroke outboard. I bought the boat and motor June30, 2016. Jul 2, 2009 · May 2, 2003 6,027 #5. All models are sold with a propeller. It most likely is the carb, The little brass tube that runs in front of the trottle plate if clogged or if it has a small hole (pin size) will make it not idle. Simply twist it open and monitor your engine for improvement. Hi, I have a 92 Mercury outboard 60 HP that does the same thing. All times are GMT -6 Mercury 150 4 s issue Motors and Props Sep 16, 2011 I have a 2005 Mercury 115 hp 4stroke. From day one the engine had a bit of a ringing sound in idle - no big deal. May 21, 2004 Re: Seafoam in new 4-stroke. Find a Dealer Mercury 2-stroke outboard motors are highly regarded in the boating world for their reliability, performance, and efficiency. My name is***** have a 2015 Mercury 115 efi 4 stroke Went to put it in the water a couple of weeks ago and it ran fine for about 5 minutes and just quit. Engine STILL barely idles and will shut down (very rough idle) I was told by a mobile mechanic that I. There are some guys on here with motors from the 30's and 40's!! 0 Thread (s) Help please - 2002 Mercury 9 I realise that this is a bit of a smaller motor than most here are used to but I guess 2 stroke outboards are much the same when it comes to troubleshooting regardless of size. Just some additional background information: The motor has been sitting for a year and half, I was using it with a new fuel can with brand new gasoline (purchased that day) in it. Jul 1, 2005 Re: 2002 50 HP Mercury rough idle It starts easy but is rough from the gitgo. The engine is idling somewhere between 2800-3200 rpm, and occasionally drops down to. I have changed the fuel filter due to the old one looking very bad. Mercury & Mariner Outboards. Advertisement The 1950s. Bad news. However, like any mechanical device, it is not immune to issues. Yesterday, Mercury, which describes itself as a bank for startups, restricted several accounts linked to African tech startups, TechCrunch has learned. "bout a year ago i bought a used 2003 ranger 175vs with mercury 115 (inline 4). The engine runs smooth in neutral and in reverse. The thermostat installed on your Mercury Sable's 3. While breaking in new 60 hp 4 stroke per manual boat was at dock in low idle gas stated coming out of exhaust and idle was rough, loaded boat and checked gas connections, everything OK. If it is good, then move on. Fuel burns at a constant rate depending on compression in the engine Yamalube is a line of regular and synthetic two-stroke engine oils manufactured by the Yamaha Motor Corp. Messages Feb 12, 2007 Re: Rough running 20 hp Mercury. The engine goes into this mode due to over heat This engine has many sensors on it for different functions that will sound the alarm. I have a newer (2000) Mercury 9. This ensures that the crankcase bearings, piston rings and all other moving. 6 Common Suzuki 140 Outboard Problems: 1. I had a friend tell me it has a little water in. The flywheel on an outboard will need to be removed when repairs are needed such as the motor not starting properly. While pushing out of the dock, the low voltage (4 short beeps every 2 minutes) alarm began sounding. The one that we fear the most is uneven compression. I have a 2002 Merc 4HP/4 Stroke. When you start the engine, there is no problem. Called dealer he said not to worry probably bad gas. Motor runs fine no missing no alarms. The idea was to create a mid-range four-stroke engine that offered the reliability, fuel economy, and ease of use of a modern four-stroke, but at a much lower price-point than the Verado line could meet0-liter displacement powerhead weighing 455. busted newspaper hidalgo county facebook If you are in the market for a reliable and high-performing outboard motor, look no further than Mercury. If your new FourStroke has been broken correctly (according to Mercury recommendations) and operated for a few months under normal bass fishing conditions, the first maintenance usually occurs at the 100-hour mark. The right propeller size should be used in a boat. I'm not sure if Mercury was still using the Yamaha powerhead in 2004, but here is a picture of my 2001 IAC valve that I've had to clean every now and then when I start having idling issues. I had to let the boat sit for about a month recently. I have new spark plugs … read more Mar 26, 2022 · Mercury outboard 4 stroke that is suddenly running rough and red electronic light stay on Probably loss than 70 hrs on engine Mechanic's Assistant: Do the running lights flicker at all? When did you last replace the bulbs? No flicker will restart but still runs rough and sound different Sep 25, 2010 · 61 #1. ) I have seen many, many, posts from all kinds of folk suffering the same kind of problem on all makes and sizes of outboard engines It runs rough at about 2500 rpm and up to about 3600. In idle mode without any gear (forward or backward) the engine runs fine. please let me know as I am having the exact same problemand exact same resultsa lot of time and $$$$$thanks in advance. However, like any mechanical device, they can occasionally encounter issues and require troubleshooting. If all is normal, 2-stroke idle is acceptable. 100 hour service was performed and there is no water in the fuel. In idle out of gear the motor runs absolutely smooth. My 1998 Yamaha 2-Stroke starts easily and will idle and ***** all day long. One of the most common Yamaha 115 4-stroke problems is a bad fuel pump. Idles great then when I rev it up under power it will cut our and stop running i have a 1996 mercury 4 stroke outboard 50 hp on my pontoon boat. It starts fine, idles great. May 21, 2004 Re: Seafoam in new 4-stroke. Weak or faulty Ignition System: = Rough Idle. If it is low, then the fuel pressure needs to be checked out of the lower pressure pump. Called dealer he said not to worry probably bad gas. Only use factory-recommended parts and lubricants. Has anyone else had this problem or knows what causes it?? Faulty Idle Bleed Recirculation System: Usually, a clogged or stuck check valve, or clogged or leaking hose. At idol it would seem to be water intrusion which is not your case. kawasaki krx forums Quicksilver also makes one that is called a nemesis, and it seems to have really good test results as well Like. Just bought a 2004 alumacraft magnum 165 cs has a mercury 50hp 4 stroke EFI outboard on it with very few hours, I am wondering how to fix the problem with the outboard cutting out as i accelerate. Troubleshooting and figuring out where the issues are. Merc 9. Started idling and running rough and finally would not stay running. Re: 2002 75hp mercury rough idle. 2006 MERCURY 60-HP FOURSTROKE: Rough Idle, Won't Plane, Power Lost, BEEP BEEP BEEP - Moderated Discussion Areas Hop to: Could Someone Tell Me Some Of The Basic Problems To Look For On My 2002 Merc It Starts Good And Runs Good At Low And Moderate Speeds, But Will Not Go Over 3800 To 4000 Rpm. Users claimed that the outboard motor runs irregularly or unevenly while they put it neutral or out of gear. I have a 2006 year model mercury 90 hp 2 stroke, it runs great once started. Essentially what I'm saying is this. The most common signs of a bad stator in a Mercury outboard engine are problems with engine activation, lack of power, and misfiring. That's just one of consequences of the 4 stroke outboard. Dad and I bought a 60hp Merc this winter to replace our 45 Chrysler. New Suzuki 150 losing power and running rough under load. Mercury Systems Inc (NASDAQ:MRCY) reported a 3% decline in organic earnings for the fiscal fourth quarter and announced disappointing guidance for. 08-09-2018, 12:03 PM Sometimes when trying to start it acts like a dead or weak battery. Find a Dealer Vice Admiral Joined Apr 10, 2007 Messages 5,617 Sep 28, 2011 #4 Re: 90 HP Mercury won't accelerate past 3000 rpm The motors needs to make power are few, Compression, you've nailed that one down, all looks fine as far as ring seal. Features: 4-stroke technology-quiet, environmentally friendly, 40% more fuel efficient than comparable 2-stroke engines, smooth running/exceptional idling Start: Manual, with decompression system. Above that it runs smooth and has plenty of pep, gets right up on plane. By Will Charpentier Mercury Outboards Repair Manual -- 2. Parts of video were not recorded as my camera g. I know what your problem is, a four inch hose ( (a 20$ part ) inside the fuel pump failed, and is filling up your crank case oil. Hoping someone with more knowledge of 4stroke outboards can help me out. The 1:100 ratio of fuel mix is a ratio of one part TCW-3 outboard engine oil to every 100 parts of fuel. rat breeders near me Specialties: Florida 4 Stroke Outboards, located in Tarpon Springs, Florida specializes in the servicing, repairing, and rebuilding of all 4 stroke outboards 40hp and up, Yamaha, Suzuki, and Mercury. 5L motors (Carb, EFI, Optimax or Racing). The Mercury missions were an integral step in space exploration. Outboard motor manufacturers recommend professional end-of-season servicing before the motor is stored for winter. If you have a two-stroke outboard motor, you must add oil to the fuel to lubricate the engine. Vocational, Technical or Trade Scho. I have a 150 hp mercury four stroke outboard model number 115013HD ser number 1B953261. A quick video on Distributor issues. 0 no power under load. the did not hook the water pressure guage. New member #1. It starts ok, then after it passes 2400 Rpms usulaay in 10-20 seconds in shuts off. Jun 13, 2010 Re: Mercury 60hp Efi Bigfoot Stalling. 4K subscribers Subscribed 224 143K views 6 years ago. your description points toward fuel or an electrical issue being A a restricted fuel situation. Oct 26, 2013 · Started idling and running rough and finally would not stay running. You fear it would rip right off the transom. A common problem on these engines is the fuel pump diaphragm leaking. Now, let's talk about those in detail.
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they cleaned the carbs (even though they were clean)changed. May 29, 2011 · Hey Charles, I have a 1993 115 HP Mercury 4 cylinder 2 stroke outboard. Has anyone else had this problem or knows what causes it?? Faulty Idle Bleed Recirculation System: Usually, a clogged or stuck check valve, or clogged or leaking hose. Learn about the individual missions that made up Project Mercury, starting with Shepard's Freedom 7 Although a stroke is more likely to occur in men, women have an increased lifetime risk of suffering from one someday. There is no chance of any leakages. This issue can be caused by a variety of factors, such as a blocked water intake, a damaged impeller, or a clogged cooling system. Above that it runs smooth and has plenty of pep, gets right up on plane. The thermostat installed on your Mercury Sable's 3. Possible Causes and Solutions: Low or No … FIXED my rough Idle + stall problem 900 -2000 RPM running hot 60HP EFI Mercury Outboard 2005 Four stroke engine! The engine starts fine and after runing for. I have replaced the plugs and fuel filter and had the injectors cleaned. (You will also note you tach behaving erratically or, dying. Re: 04 Merc 115 hp 4 stroke efi idling problem. Water vapor enters the crankcase of all motors from the atmosphere, and as a by-product of combustion. However, like any mechanical device, they can occasionally encounter issues and require troubleshooting. It started this crazy idling/stalling issue just ---coincidentally after i topped the boat tank off with gasoline. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright. My 2005 115hp 4 stroke EFI starts instantly and runs fairly. From day one the engine had a bit of a ringing sound in idle - no big deal. Add a fresh set of spark plugs, change the oil and filter on a four-stroke, then add gas and. 9 4 stroke for a pontoon boat 4 years ago. I drained all of the fuel out of it, cleaned the fuel supply module out, flushed the lines, cleaned the injectors, all are spraying good, installed new fuel. 9. Causes Of Volvo Penta Vibration. I drained all the old gas and put in new. Everything from electrical and phone lines to cable and speaker wires need to be roughed. Deliveroops. long tail kit The motor runs great over about 2500 RPM, but when running at low RPM while trailering, idling, etc. Recently, I have developed a problem where it will hardly ever stay running at idle. My 2005 [Mercury 60-HP FOURSTROKE Bigfoot EFI outboard engine] runs rough, stutters, quivers, quakes, and shimmies intermittently between 900- and 1,800-RPM. Jul 20, 2010 · Jul 20, 2010 This is my first post. It started right up and sounded just fine. Inadequate fuel supply is a common issue, either from pinched hoses or a lack of fuel in the gas tank (s). I have an 02 115 mer 4 stroke. Vocational, Technical or Trade Scho. In any of those cases, reliability is far better than it was in decades past, fuel efficiency has increased, and problems like smoky exhaust and ear-splitting sound levels are ancient history. Why is my Yamaha 25 HP 4 Stroke outboard running rough? A Yamaha 25 HP 4 Stroke outboard may run rough due to a variety of reasons, such as dirty fuel injectors, fouled spark plugs, or a clogged air filter. I Kill Each Cylinder Individually And. I changed plugs and checked for. Also, my tablet/vesselview was reporting a neutral. photodrop Jul 1, 2005 Re: 2002 50 HP Mercury rough idle It starts easy but is rough from the gitgo. In the Freddie Mercury biopic, “Bohemian Rhapsody,” there’s a scene in which a family member scolds Mercury The 1950s Classic Mercury Cars Channel covers popular antique Mercurys from the decade. It has run fine since new. It runs very rough, and you cannot get full performance. This is a common problem and is usually caused by a sticking timer base under the flywheel or fouled, clogged carburetors, however… also check the carburetor linkages, compression, spark, and the timer base as follows. Even when they try to start the engine. Your local Mercury Authorized Dealer is the best place to see and purchase Mercury engines, parts and accessories, and to get expert support when you need it. The high pressure filter requires a special tool, and the. hose. The problem is that when I am running at full throttle the engine suddenly dies. engine starts and runs if you give it some throttle, fuel psi is 42-44psi From one day to the next my Mercury Outboard would no longer get past 3000 RPM. Consult your owner's manual to check items that may be unique to your motor. I have a can on the shelf, I will have to read it. Rough running can have a variety of causes, including fuel pump failure, air-fuel mixture issues, ignition system problems, and others. Never actually stalls though. gia paloma Good Morning - I recently bought a 2003 90 HP 4 stroke Mercury outboard. It idles very rough. Smoke does not go away after running. It starts, idles somewhat roughly, dies after a few minutes. I also put in new plugs. the grinding is the clutch dogs skipping across each other. The engine will run on all 4 cylinders but will be 'kicking' or roughing. But it still doesn't have any power or reaching RPMs above 4K while in the water? Below are my notes, sorry for the long post but I figured more information is better. I know what your problem is, a four inch hose ( (a 20$ part ) inside the fuel pump failed, and is filling up your crank case oil. I bought the boat from my father in-law who said it did not have any issues So when i bought it there was an issue with fuel starvation due to the fuel pump cavity not being drained for winter storage last year 07-18-2022 07:54 PM. Spits and sputters, won't idle, dies, can restart with full throttle as it floods out once warm. I had to let the boat sit for about a month recently. Find out how to fix a rough running lawn mower engine by adjusting the spark plug gap, cleaning air and fuel filters, and switching to ethanol-free gas. It started this crazy idling/stalling issue just ---coincidentally after i topped the boat tank off with gasoline. FourStroke ProKicker 9 With easy-starting EFI technology, a ProKicker™ outboard is a reliable fishing partner that's ready to go when you are. The one that we fear the most is uneven compression 2006 50HP 4 stroke EFI After several trips to the certified mechanic and much$$, they now tell me it's the injectors. Also checked the spark, firing on all 4 cyl's. Knowing why an outboard idles rough is only the beginning, here is what you need to do to figure out why and how to. Because your Suzuki outboard won't start in gear, ensure the engine is in neutral. Steering Type: Tiller (2. 9 hp 4-stroke kicker motor was not running well.
I have had it to one repair shop who cleaned the carbs, ran sea-foam through it. B The timing is off, C The stator could be affected and D coils, wires grounds plugs etc , It also could be. 1,337. If it is good, then move on. Next, without delay, pull the spark plugs, drain the cylinders and spray an entire can of quality fogging oil (such as Lear Chemical Corrosion Block) throughout, rotating the crankshaft to save the cylinders. allegheny county courts Re: Mercury 50 hp bigfoot with idling / running issues. I stopped to fish a spot for about twenty minutes, started my boat up, put it into gear and couldn't get about 3,000 RPM. New inline fuel filter. But I'm in the second Mercury outboard that I had bought new, Then I'm not used to outboard problems. Shift with authority. There is no reason to "slide" the lever into gear. He came from a Parsi family that had roots in India. At the end of last season the engine started running really rough, kind of stuttering and then sometimes revving back up in mid throttle it seems to run ok at idle. ohdoc gtlvisitme There is a fine independent marine mechanic shop out of Greenville South Carolina that closely monitors the website. The engine is a 2017 Mercury 150 4-stroke mounted on a Tracker boat. I removed the rail and the regulator diaphragms. Engine Running Rough At Idle: At low RPMs, the engine seems to run 'rough'. I cleaned/re-built the carbs with the yamaha carb kits and installed a 30GPH Racor fuel water separator. The checklist for an outboard that remains running poorly at idle is the same as for when it stalls while idling. I have a 2001 40 hp Mercury carbureted 4 stroke 4 cylinder engine. jonathon taylor Pulled it out of - Answered by a verified Marine Mechanic. Oct 26, 2020 · VERY intermittent problem continues for over a year, can't seem to identify the problem. 0g654534, 1998 200efi Motor starts hard,must advance throttle every time to get started,super smokey and rough idle (if you can keep it running). Mercury 60 Hp 4 stroke is a reliable outboard motor. 5L motors (Carb, EFI, Optimax or Racing).
Sometimes it would take just a couple of minutes and then instantaneously the problem dissapeared, like a switch was thrown or something broke loose. In this blog post, we'll explore common problems associated with Mercury 2-stroke outboard engines and provide detailed, step-by-step solutions for fixing them. We are having intermittent issues with performance. When the problem is happening, the motor will run smoothly at idle and at low throttle while in forward gear. 6 beeps "on start-up OR during a running failure" indicates a fault in any of the following: MAT sensor (Manifold Temperature), MAP (Manifold Pressure) sensor, TPS (throttle position sensor) or the ECM itself (Flash Check Summary). 035" (35 thousandths of an inch). Does this sound right? Engine starts fine and idles though somewhat roughly. Replaced all gaskets in the carbs, new plugs, still wont start and run unless i have the accelerator turned up Your model has two fuel pumps and a vapor separator, any of which could be causing your issue. Mercury 4Stroke EFI BigFoot 50 hp 2006: The RPM vary and then the engine stalls when I try to set the RPM between 1000 and 2000. Outboard motor designs vary depending on make and model, but all operate on similar principles. Outboard motor manufacturers recommend professional end-of-season servicing before the motor is stored for winter. And the ignition coil failure is the main cause of it. Essentially what I'm saying is this. This is referred to as "Making oil". statefarm auto pay I can run it at high idle. I have replaced the plugs and fuel filter and had the injectors cleaned. 3 Mercruiser hard start warm, Mercruiser 350 mag mpi problems, Mercruiser 350 mag mpi troubleshooting, Mercruiser 3. 2010 Mercury outboard 50 hp 4 stroke does not idle. Although a stroke is more likely to occur in men, women have. I'm frustrated as to the possible cause. About a month ago I was out fishing running up and down the lake with no issues. Rough running can have a variety of causes, including fuel pump failure, air-fuel mixture issues, ignition system problems, and others. Mercury was still making those older-design, high-emission, two-stroke-power-cycle outboard engines until c. The following information is a list of possible causes and corrective actions needed to fix a Mercury outboard that hesitates on acceleration. I have an issue with my 2006 Mercury 50 HP EFI 4 Stroke motor that I can't figure out and either can the mechanics I brought it too. 0l engine is what allows coolant to flow from the radiator to the engine. My 2002 Merc 115 ELPTO (0T464942) is giving me low-end rpm problems while running below around 1300 rpm down to idle. Jun 16, 2013 · My 2007 Mercury (by Tohatsu) 9. The motor performs normally from low speed to WOT however when at idle and out of gear the motor is blowing bubbles from the prop which I think means that the exhaust bypass is not working correctly. Internal Damage: Persistent irregular sounds may signal serious internal damage. In a nutshell, when I power my engine over 4900 RPMs, I frequently hear the infamous 6 beeps from the. 09-14-2019, 10:15 PM. I can run it at high idle. compressor for vendo coke machine I use the motor for walleye fishing *****ing at 17 MPH. I have a 115hp Mercury 4-stroke motor that runs rough at low RPM, won't idle and appears like it is running too. Checked the fuel presure it is 38 new filters had the vts serviced, carbon cleaned out of the motor, good spark diaonostic test has no codes , the comprssion is 140 in all of the cyls. Hi everyone, I have a 2000 model mercury 75hp carb motor that runs kind of rough sometimes. 1999 Mercury 250 two stroke EFI, (I have had for a few years). But there are some common Mercury 50 HP 4 Stroke Problems that came as complaints, and you should know about them. Now for the fix: I pulled the carburetor and took apart for cleaning with gumout and found no goobers, varnish, maybe. The engine is going into what is called guardian mode which will not let the engine exceed 2500 rpms. However, like any other mechanical device, Mercury 4-stroke outboards might face occasional problems that require troubleshooting and fixing. almost like a loss of fuel. The Active Trim system is compatible with most Mercury four-stroke outboards from 40hp and up, Mercury two-stroke outboards with SmartCraft® system capabilities, and SmartCraft-capable gas and diesel MerCruiser® sterndrive engines with digital trim senders. 2016 60 hp 4 stroke mercury outboard runs rough at low RPMs 2016 60 hp 4 stroke mercury outboard runs rough at low RPMs then shuts off. Problem #1: Overheating. Re: Mercury 50 hp bigfoot with idling / running issues. If all is normal, 2-stroke idle is acceptable. Apr 27, 2009 Re: Merc 115 EFI 4 Stroke running rough. It seems that sometimes I would start the motor and I was missing on a … In rough water conditions, a good hole shot and sufficient acceleration determine the smoothness of your experience. I have a mercury 4 stroke outboard 150hp 3l that is running rough.