2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

bte52

Recruit
Joined
Aug 15, 2004
Messages
3
I have checked the FAQ's and suggested resources. Found related problems but not exact. I am at my wits end. We have a brand new 19' Trophy CC with a new 125 Mercury outboard. This boat has 14 hours on it and I have been following the break-in procedure (varying RPM and NO WOT). Since the first outing I've been experiencing what I would have to term as an engine miss at higher RPM (3000 to 4000). It's like you're moving along just fine and then the engine skips a beat or two and you feel the momentum of the boat slow and then pick right back up again. I would also describe it as the same feeling as if you were in shallow water and the prop hits the sandy bottom. The problem has been very intermittent and would always clear itself right up with no more problems so I've been waiting to take it in for the first service before saying anything. Well, today we went out and I am quite concerned. The problem has dramatically worsened. We went about 20 miles down the Wicomico River with no problems. Then it started the missing badly at around 3800 RPM. The engine bucks and you can see the tach dropping 400 to 500 RPM and then picking up again. It was really bad! This time we had to stop before continuing on because it wouldn't clear itself as it had done before. I found that by stopping and going just 6 to 10 MPH for a few minutes that I could then pickup the throttle and go 3,800 to 4,000 RPM for about 3 minutes and then it would start missing again. It took us a long time to get back to the marina but I did not want to cause any damage to the engine. I am not getting any other abnormal readings on the gauges. I don't know if this problem is fuel or fire related and I also know that it is impossible to diagnose a problem by my simple and uneducated description. I was simply hoping that someone out there may have had some similar problem and could shed some light on the subject for me. NOTE: I have returned to the dealer since writing this and they checked what they said was the obvious (fuel bulb, fuel venting, etc.) and also ran it in the test tank and on the dyno. They found one carb out of sync and repaired that and said that I should be fine. I left the dealer and went right to the river for a test run. Ran GREAT for 30 minutes and then started missing and bucking at higher RPM range. Again reduced RPM to 1,800 for 5 minutes and then could pickup RPM for 3 or 4 minutes before the problem returned. It's back at the dealer and we've been waiting for better weather as they said they want to take the boat on the water for further diagnosis. Any ideas? Thank you.
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: 2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

Welcome to iboats and let them do their job.<br /><br />I will add this, however. One of our customers had a problem with his boat since it was new. It would run fine for awhile, but die out after awhile. He brought it in several times and none of my compadres could find any problem. I finally checked the fuel pickup in the tank on a whim and the screen was mashed flat. The pickup was 1/2" too long and there was little room between the bottom of the tank and the tube allowing very little gas to pass. I think you have a fuel supply problem, not a motor problem.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: 2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

hello<br /> run it on a different tank ands check the filters. the last one I had like that someone had used silly cone as a fuel sender sealant and the anti-siphon valve was clogged with it on a brand new grady with a 225 EFI. would run great to about 5100 them fall flat.<br /> good luck and keep posting but take it back to the selling dealer so you have a record
 

bte52

Recruit
Joined
Aug 15, 2004
Messages
3
Re: 2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

Thank you WillyBWright. In my opinion you are correct. Thank you as well rodbolt. BTW, we are heading your way Saturday the 21st of August. A week in OBX is just what I need. Hopefully the boat will get fixed this week. We have stayed in the same rental home in Colington Harbour for the past 5 years. Please keep the hurricanes away for us!
 

2springers26

Seaman
Joined
May 18, 2004
Messages
63
Re: 2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

unplug the rev limiter & see if it goes away... had one last week go into rev limit every rpm but the top end...
 

bte52

Recruit
Joined
Aug 15, 2004
Messages
3
Re: 2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

Well, I have an update on this situation. The dealer has found small particles of plastic in the fuel pump diaphram. They removed them and put the boat overboard again and picked up more. Obvioulsly the fuel tank is contaminated with origins to the manufacturer (Trophy, Bayliner, Brunswick, whoever. This boat was put together in the Maryland plant). Anyway they are going to install a fuel/water filter seprator in-line and say they are confident that this will resolve my problem. I hope so. We leave for the Outer Banks and Albermarle Sound this coming Saturday. The part won't be in until Thursday and they say that they are going to go out on another test run once the filter is installed. Anybody taking any bets on what will be the outcome? Thanks again to all who replied!
 

Wellcraft 89

Petty Officer 2nd Class
Joined
Aug 5, 2002
Messages
158
Re: 2004 Mercury 125 2-Stroke (Saltwater Series) - Weird!

I would ask for a couple extra filters free of course.if the dealer isn't willing tell him to change the tank. <br />It shouldn't be your problem,its the boat manufactures.<br /><br />Sorry to be a hard --- but the buck has got to stop somewhere!<br />you paid top dollar for the boat<br /><br />Rich
 
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