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Roostertail1964.
I have a 2014 Mercury 250 ProXS on a 2014 Bass Cat Eyra. Love the boat but the motor has been increasingly hard to start first thing in the morning. When I turn the key initially, it fires, starts for a second and acts like its flooded. Turn the key and it will crank but not fire. After cranking two or three times, it fires idles a little rough, but eventualy straightens out. The motor will start fine the remainder of the day. If the boat sets for a day or two before using again, I experience the same problems. I have had the boat to the dealership (3) times and the mechanic, very good wrench, can find nothing wrong. I just replaced the battery with a Northstar series 31. I checked the voltage of the battery after charging – 12.9V. I left the engine idle for approximately five minutes and checked the voltage – 13.4V. I know that the battery is capable of cranking the Opti. Puzzled in Pennsylvania…
Its just like doctors- if he is Stumped get another oneC.O.D. Jr. III
Engines require 3 things to run . — 1. AIR — 2. FUEL — 3. IGNITION — You have to find out which is causing the problem , then try to fix it . — Some engines are just plain cold blooded , but a fuel injected engine should just start and run if it has the required elements in the proper portions . — Im an old school mechanic , and a Yamaha guy to boot , but I remember hearing something about the Mercs having a leaky oil valve / seal somewhere in the injection system that would let oil pool up in the intake tract during storage between uses . — Cant remember it exactly , but if that was the case youd get a ton of smoke when it first fires up , and it would act just about like you described after it started . — My brothers older Mariner does this faithfully , but has never let him down yet . — Just my 2 cents worth . — Hoss
Any Mariner would be late 90s or older. This is direct injection and its in the fuel rails or pressure most likely. If they have connected it to the laptop then it should be obvious. If they are using DDT then they need to go to laptop.
My Mercury mechanic claims he hooked the laptop to it and cant find anything indicating the problem. I know that he just replaced a “tracker diaphragm” and told me that this would FIX the problem. Well I took it to the lake and hit the key, it fired, smoked, and stalled within (5) seconds. I hit the key again and it cranked but did NOT fire. Hit the key a third time, it cranked and did NOT fire. Finally, I hit the key and it fired! It smoked a LITTLE bit but idled very rough. I turned the key back off and then on and it fired and idled fine! It runs beautiful after the initial start.
Mine was doing this also and was a diaphram,but yours sounds like a leaking fuel or oil injector causing it to load up and have trouble burning it off at startup,just my opinion Im not a boat tech
Roostertail1964 wrote:My Mercury mechanic claims he hooked the laptop to it and cant find anything indicating the problem. I know that he just replaced a “tracker diaphragm” and told me that this would FIX the problem. Well I took it to the lake and hit the key, it fired, smoked, and stalled within (5) seconds. I hit the key again and it cranked but did NOT fire. Hit the key a third time, it cranked and did NOT fire. Finally, I hit the key and it fired! It smoked a LITTLE bit but idled very rough. I turned the key back off and then on and it fired and idled fine! It runs beautiful after the initial start.i had a similiar problem on a brand new 2015 pro xs and it was the fuel rails
Cougar ftd wrote:Mine was doing this also and was a diaphram,but yours sounds like a leaking fuel or oil injector causing it to load up and have trouble burning it off at startup,just my opinion Im not a boat techThis is the same problem my 08 was having. Always seemed like it was flooded and rough starting. Turned out my mechanic found a small pin hole in the diaphragm that was allowing to mush fuel in the mixture. Problem solved
I used the boat twice since the mechanic replaced the diaphragm and the first time out the motor started extremely rough! I hit the key and it fired, ran for about two seconds and shut off! The motor acted as though it was flooded. I turned the key a second time and it cranked but did NOT fire. I repeated the process and the motor cranked once again without firing. Finally, the next time it started and ran a little rough. I turned the motor off and restarted it and it idled beautifully! The boat ran perfect the rest of the day. I called the dealership and told the mechanic my experience. I asked if he thought that it could be a leaking injector or the fuel rails and he said that the computer diagnostics indicated that it was the diaphragm. He said if I wasnt happy with the performance that I should bring it back to the shop, an hour and a half away, and he would take another look at it.I hooked the muffs up to the motor the next day at the house and it did start the first time, however it did idle a little rough.I usually experience my poorest performance when the motor sits for a couple days between use. Im going to try the motor once again tomorrow at home to see how it performs after sitting 3-4 days. If the problem persists, well I guess its back to the dealership.
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