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Random Quote: 4' to 6' is still better than 9 to 5
I just recently bought a used boat with a 2002 Merc 125 (carb) Saltwater series and it's already giving me trouble.
This is a long post, but I really didn't know how to supply all the vital info in any less words. Thanks for reading on
It was purchased new in April, 2002. The past owner had a stroke after using the boat only 5 times (8 hrs, supposedly), so it was sitting up since Oct, 2002. He still had 1/2 tank of break-in (double oil) fuel in the boat.
I used the motor for 4-6 hrs the previous weekend and I burned about 30 gal of fuel through the motor. Part of that was the old fuel and the rest was fresh.
I was prepared to use the boat heavily again this weekend. Here's what I did in preparation. I fueled it up again. Some of that is still running some oil-rich gas. I changed the plugs, the fuel/water separator and sprayed ALL AREAS under the cowling with Boeshield T-9.
The boat ran fine at idle for 15 min from my house through the no-wake zones and then another 10 min to the first fishing spot. I backed off the throttle and it killed. When I attempted to restart, it was obvious it was not behaving correctly. I was able to run the motor at about 2000 RPM's ... BUT THIS WAS VERY NEAR FULL THROTTLE. Any attempt to back off this throttle setting and the motor killed.
I got back to the dock and recruited a couple guys that are a little more motor savvy than me. We changed plugs again. We bypassed the fuel system and ran from a 6-gal aux tank.
It continues to exhibit the exact same symptoms. It will only run at higher RPM's but it is a throttle setting that is near full-throttle and should be turning even more RPM's. It kills as you back off on the throttle to approximately 2/3 to 1/2 throttle.
My friends thinks it's "electrical". That don't help much. I'm not going to be fixing the motor myself anyway, but I'm looking for additional ideas.
The owner's manual states that the motor runs on 2 (of 4) cyclinders and lower RPM's. It almost seems to me that this feature is malfuntioning ... meaning I'm getting zero cylinders at low RPM's and 2 cylinders at higher throttle settings.
Of course, I'm very dissapointed that a 2002 motor of any brand with almost no hours would have a problem of any kind. It really doesn't seem like 9 months is a long time for a motor to sit up. Does this seem like something that sitting up would have contributed to?
Finally, this motor is out of warranty (one year) and I'm the 2nd owner. If this requires some kind of "covered" repair, what do ya'll think is the likelyhood Mercury would budge on the coverage period. It's 2 months out of warranty.
Thanks Everyone!!!!
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Fishin-Fanatic
Get In! Sit Down! Shut Up! Hold On!
I doubt theres anything seriously wrong with it...more than likely it will turn out to be something small and easily fixed.
Take it to the dealer the original owner bought it from (if it's closebye) and explain the dilemma and how it's still being run in - I reckon they will hopefully do the right thing and get it going right for you without gouging you for the repair.
I can't see that sitting up for 9 months should do it any harm at all.
I suspect this thing will have some "rev limiter / limp home mode" thats restricting you to 2000 rpm's....once a sensor kicks in due to temp increase.
Is the two cycle oil tank full?.
Someone with the same motor may have some clues and chip in here with any luck.
I think troutster is on the right track. Sounds like the engine system is limiting you to 2000 rpm for a fault in the system. oil.. overheat.. something.....
That said.... I had a frend who had that same motor... on a 1998...it was easy to start in the morning.. but hard to start during the day when fishing. go figure. He sold it and the boat after 2 years... poor guy who bought it... seized a piston first trip out.
First, will it go above 2000 rpm at wide open throttle ? Try it with a load and without.
Second, go to your local auto parts store (or perhaps a good hardware store) and buy a cheap spark tester. They usually look like a small screwdriver with a clear handle. When you hold it near (not touching) a firing spark plug it will flash. The flash is VERY hard to see in sunlight.
Last find a place where it is very dark (actually best in a darkened garaged with water muffs on). Have someone else at the controls. With the hood off, turn out all the lights. See if you are getting any "stray" sparks off of the coils, wires, plugs, etc.
Warning, being near a running engine in the dark is DANGEROUS !
I'm with the rest of them, got to be something simple. Get a spark tester, or very carefully pull one plug wire at a time to find the cylinders that are not firing, if all are firing it has to be fuel related. I see where you isolated the fuel system but that doesn't take into account what is already in the carbs. Pull the fuel filter under the cowling and see if anything is in it. Also I see in your post where you changed fuel/water separator, check and make sure it is not full of air.
And most of all keep your head up this is just a little teething problem, it will be no time before your back on the water.
I'll admit; sounds electrical BUT, do you have a filter on the engine... just as the gas goes into motor? Check it out! Also watch that WOT on the ear muffs...if that should kick in, you're gonna lose a motor. Finally do you have a little (looks like a tire air valve) valve on the motor with a 'red' handle; it's used to fog motor? Can't remember right now, it's either supossed to be up or down! Thes are simple things to check. Good Ludk!
Boston Whaler, "MUMBLER", 24' Outrage, twin 175 HP Evinrude Ocean Pros. Snowball, the cat...
I agree with Trouty. I bet it is a sensor or something. My 1999 Evinrude did something simular once, it turned out to be the stator or something wasn't putting out enough voltage and the computer wouldn't let it fire, I think it will be something like this. Try to go to the dealer where it was purchased from.
Just wanted to give you a piece of mind. I own the same 2002 125 Merc and have had no problems. I think you own a classic motor and your problems should be minor.
If anyone is interested I'm looking to upgrade and I'm selling my boat (18 ft Manatee deep vee) and Motor. The motor has around 50 hours on it and it has a extended warrantee until 111/06
Milton, I'm betting its trash in the carbs. I had this problem constantly with my Yamaha. That boat sat for a while, so there is probably a little debris in the tank getting stirred up or something like that.
Those Merc 125's are relly good motors, its proabaly something simple. Take her to Morgan.
I'm not terribly discouraged ... yet!! I have resonable faith that there is simple low(ish) cost solution.
I have a neighbor that is quite handy. I will show him some of your suggestions and see if I can recruit him for a hour or so of diagnostics.
The original selling dealer is a top notch dealership, but they are a long-time Johnson/Evinrude shop. They are a long-time Cape Horn dealer, too, and all the boats that they sell with Merc's are factory pre-rigs. I suppose they should still know how to work on them, though.
If the work won't be done under warranty, I'd rather bring it to a shop that I have a lot of confidence in and that would be the same shop that's going to rig the boat ... Morgan Marine about 5 minutes from my house.
Once again, I really appreciate all the good common sense ideas everyone has come up with.
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Fishin-Fanatic
Get In! Sit Down! Shut Up! Hold On!
dont forget to look at the throttle cable it could be causing a problem it could have streched i have the same exact motor 125 salt water series and have had a lick of trouble with it
CARBS CARBS CARBS!!!! I'll bet it was never winterized after the guy had the stroke so all that gas in the tank and engine was old and starting to gum up. It then clogged the jets in the carbs so the engine isn't getting enough fuel.
Take the carbs off and clean them out. You can get rebuild kits from the dealer for a few bucks each. It's basically all new gaskets for the carbs.
You will also need to drain the tank of all remaining fuel and have it cleaned out to prevent the problem from reoccurring.
Probably wouldn't hurt to replace all of the fuel lines inside the engine either.
Don't expect Merc. to help you w/ this one since the problem is not due to a fault w/ the engine.
This is a guess...but being you ran fine for 4-6 hrs the previous weekend and burned about 30 gals of fuel I doubt the carbs are gummed up.
However...you may have sucked something in there from the main fuel tank.
I'll go with Trouty... a bad sensor etc....OR you have something wrong that is triggering a sensor but in that case you would think an alarm would pop.
You have a lot of clues in your note....print it off and take it to the dealership or a good Merc mechanic before you take anything apart. I'll bet if this is minor they'll have a pretty good idea what is going on.
I don't want to change the topic here over to my situation, but it is very similar....
I've now run my 2003 Johnson90/2 for about 15 hours total (bought new about 2 months ago). It has run flawless to date...but on Sunday, I went out and it would flood itself out at idle so that only one or 2 cylinders were firing, and eventually die....if I gave it WOT it would clear up and run well (although rpm's were down from 5,000 to about 4,800). I'll be taking it to the dealer this week, but wanted a few ideas from you guys. My thought is the carbs need to be adjusted, and probably part of the 10 hour service that I'm due for. Thoughts? thanks.
I guess I should have mention that this exact same thing happened to my 50 Yamaha last year. It ran fine for approx. 6 miles from my dock to the Bay Bridge where I was going to jig the pilings for stripers. When I pulled the trottle back and got ready to make my first cast, the engine quit. I could get it to start w/ the idle speed lever on the side mount control advanced, but as soon as I dropped it down to shift, she died. I eventually got going by dropping the idle, shift and going to full throttle in about half a second. To get through the 6 mph zones on my way back to the dock, I had to keep the choke on.
Try engaging the choke and I bet it runs better.
I still think it's the carbs.
Tony, do you have a fuel filter/water separator installed? If not, you may have some debris preventing the needle/seat in the carb from closing entirely and thus flooding the corresponding cyl.
The mechanic said it is something callled the "trigger" that was bad. The part is under the flywheel and it is before, or below, the stator coil.
All mechanical things are foreign to me. I tried to describe it the way he described it to me.
The boat goes back in the water this evening. I'll let ya'll know if it's fixed for good. It cost $100 for the part ... not sure of the labor charge because it was lumped in with all the rigging I had done.
Still not real happy that anything would break on a 2002 engine, but I'll forget about it soon enough if things don't keep breaking.
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Fishin-Fanatic
Get In! Sit Down! Shut Up! Hold On!
New Motor Not Running ... Any Ideas? 
Thes are simple things to check. Good Ludk! 
Boston Whaler, "MUMBLER", 24' Outrage, twin 175 HP Evinrude Ocean Pros. 
Snowball, the cat... 
