mercury efi failure problem?? please help suggestions needed
 

225 merc efi injected , runs great at idle , when throttling up to over 2k rpm it loses power and stalls. Put back in neutral and it fires right up! Go to throttle it wont even get on plane and same thing loses power and stalls

Re: mercury efi failure problem?? please help suggestions needed
 

Not sure if same. Likely yes.

In Bombardier- Evinrude/Johnson when have computer problem or overheat problems they rev limit it. Sounds like it'll rip itself to pieces if you throttle past 2500 rpms. It's a "get you home" feature.

May likely be the same thing. If so it's likely not the fuel injection at all. They have computer diagnostics will tell you problem in 60 seconds.

Try Anglers in Sea Bright if you're looking for GREAT Merc work

Re: mercury efi failure problem?? please help suggestions needed
 

Is there any audible alarm when this happens?? Is so, like Frank says, it could be going into safe mode... That limits the RPMs when the engine detects an issue like lack of oil or overheating.

If not, sounds like it might be starving for fuel. First thing I would try is running it off a portable tank. If it runs OK then you know you have an issue in your fuel system on the boat.

Once you elimate the fuel system on your boat, I would take it to a mechanic with diagnotic tools to trouble shoot.

Re: mercury efi failure problem?? please help suggestions needed
 

What year is it? Is it a DFI with the high pressure injector on top?
I had a pair of 2002s and the compressor went on top and did same thing basically.

Re: mercury efi failure problem?? please help suggestions needed
 

No alarms , at all , it revs up and shuts down , no warning ! But motor completely shuts down .....turn key and starts right back up. If i put in neutral and rev up i can get it up to 5000 no problem. If i rev up under load it shuts down........

Re: mercury efi failure problem?? please help suggestions needed
 

I would just call mercury I have a 2005 optimax I had some problems with they told me everything to check out over the phone. I ordered the part and fixed it myself saved a lot of money. They have good customer service this is my first mercury. It won't hurt to call and see if they can help good luck +1-888-427-5373

Re: mercury efi failure problem?? please help suggestions needed
 

Bassappeal aren't you local to Neptune area?? It's that or Pa I'm not sure, may have a guy with the merc puter if your close...email me for #

Re: mercury efi failure problem?? please help suggestions needed
 

D fish im located in old bridge nj middlesex county , boat is located in matawan nj close to keyport

Re: mercury efi failure problem?? please help suggestions needed
 

Called mercury , and they told me more or less its a fuel issue if no alarms are sounding ....so i have to run through my whole fuel system start to finish and check everything ....to be continued

.....


Dfish if you guy is local and can run a diagnostic or let me borrow the tool please let me know ...the engine is 1996 ...

Re: mercury efi failure problem?? please help suggestions needed
 

Bass
Seen a similar issue with a faulty fuel tank check valve. There was enough flow to run the engine but not under a load. The valve is normally located on the elbow of the fuel line where it leaves the tank. Good luck, hope this helps.

Re: mercury efi failure problem?? please help suggestions needed
 

If they are thinking it's a fuel issue easiest way to find out is to hook your motor up directly to a portable tank.... If that does not resolve your issue you know everything on the boat is likley OK. If it does resolve the issue then keep on working backwards from the motor introducing more of your fuel delivery system inline with the portable tank. Put it just before the primer ball, then the filter, then the line coming out of your boat fuel tank until you get the same issue and you have found your culprit.

If it turns out the issue is in the tank, the check valve PA Fire mentioned is a usual suspect. One other thing to before that would be your fuel vent line. If it's clogged it can also restrick the flow of fuel. Easiest way to check if the vent is clogged is to simply open your fuel cap which allows your tank to vent and try and run the boat...

Good luck. Frustrating stuff but using the protable tank will help you from replacing uneeded parts.

Re: mercury efi failure problem?? please help suggestions needed
 

Mercury is thinking diaphrams on fuel pump maybe worn also , so at this point waiting on saturday to even start to crack into what why when and how !

Re: mercury efi failure problem?? please help suggestions needed
 

Well , rebuilt my fuel pump diaphrams , cleaned regulator , changed filters , emptied vst , check fuel lines , and still the same problem ......then pulled the plugs and they seemed fouled out , so i glass beaded them put em back in and seemed to be slightly better but still rough......im assuming new plugs and i should be ok .....go figure !

Re: mercury efi failure problem?? please help suggestions needed
 

I forgot that , i put some seafoam in and never changed plugs after ....doi !!!

Re: mercury efi failure problem?? please help suggestions needed
 

when the neutral selector switch starts to stick you can get that same issue, But it will usually throw a code.
it wont let it go over 2500 while it says its in neutral.( just changed my second one )

I also had a piece of aluminum slag stick in my check valve on the tank and it did the exact same thing.

SO different things totally can cause the same symtoms

Re: mercury efi failure problem?? please help suggestions needed
 

After i cleaned the plugs it ran ruff from 2000 -3000 then ramped up fast to 5000 rpm backed down to prevent over rev......and it kinda stalled out ....so ....what ever the problem i dont think check valve because it only gives me problems between 2-3k rpm ....i was running ngk plugs bought , champions marine plugs and need to install see what happens ....i can tell u it is frustrating to say the least.......but i do think seafoam may be part of my problem ....i wanna get out and run every ounce of fuel out of it ...and go fresh ....