Outboard trouble shooting thread!!!!

There are many threads for specific outboard trouble shooting. Maybe, if we keep it consolidated, there is a better chance of getting answers and trouble shooting ideas??????

Dodad, Try opening the bottom plug of the lower unit and see if any water comes out, or if it is milky white, as both would indicate a seal leak. Also look at your prop closely for any fishing line, many times fishing line will cause a leak. Also, if it is coming out your prop it may be oil that you mixed with your gas. This can happen if you idle too much. Also, any chance this is the first time you've ran her this year. Just curious if it could be unburned fogging oil from last Fall when you laid her up.

Nubby........If your motor is the same as a Yamaha, the squeal you hear is coming from where the drive shaft goes through a bushing near the motor. the bushing is supposed to be greased every year, but if not, over time it dries out. It does not hurt anything, but it is annoying. My 60 Yamaha does it all the time. When I run the motor fast and then slow down, it will squeal from 2200 rpm's to about 1600 rpm's. It is the only rpm's that it squeals at. Google Yamaha squealing and you can read up on it. I know you have a Mercury, but a lot of these motors share the same designs.

I have a '97 Merc LS that runs like a top, but I just noticed that I am leaking lower unit lube through the prop area. I see it inside the prop hub. Is this something that a novice can fix or does it need to go into the shop? Thanks, Dodad

I've got a '97 Merc LS that runs like a top. But, just noticed I am losing lower unit lube through the prop area. I see it inside the prop hub. I ass/u/me it is a seal leak. Is this something that a novice can fix or must it go into the shop? Thanks Dodad

Mark- The bulb simply gets fuel to the carbs so your engine will start. Once the engine is up and running the fuel pump takes over. Sounds like you may have a bad bulb, there is a check valve in there to keep things tight, it would be an easy thing to check / rule out.

MarkASity, When you changed your fuel tank did you also change your fuel lines? If you are running gas with ethanol it will degrade your fuel lines over time. I had a similar issue a couple of years ago and just changed my fuel lines, put a new bulb on it and it was fine. Because of the degradation in the bulb and lines I went ahead and changed the filter as well. There is a marine grade fuel line you can get that holds up to those blended fuels. It's a little pricier up front but in the long run it sure beats having to change your lines every other year.

I have a '08 Yamaha 90hp 4 stroke powerhead, installed 3 yrs ago. Ran great until late last Aug, then it started to loose pressure in the bulb when I shut it off. Not a huge problem but I'd have to pump the bulb a couple times if I shut it off for more than 20 minutes. I thought the problem might be a slow leak in the (very) old gas tank so I replaced it this spring. Now I have to pump and pump and try to get to the started before I loose pressure and it won't start. Often I have to do this 5-6 times. Once started it runs and idles great. But after I shut it down I have to go through the "ritual" again. Sometimes it isn't too bad but it seems to be getting worse. It is a jet drive, but I don't think that should be an issue with this problem. The only things I can think of would be the fuel filter or a slight air leak somewhere in the fuel system. One other thing; I thought I had bad gas this spring because it wouldn't start, now I am wondering if the gas wasn't the problem. Thanks in advance, Mark

Hmmmmm Nubby.... Couple of thoughts. Any metal shavings on the outside of the block? If so have you checked the recoil assembly to make sure everything is good and tight? Is she pumping good water? Could be an issue with the water pump. Could also be a problem with the lower unit bearing. Have you drained the lower unit, looked for any metal shavings? They can start to howl a bit when they are going. Also, you mentioned problems at WOT but not at idle. You sure you have her mixed 50 to 1? It can run much leaner at low RPM's. Lots of things to check...

Thanks for the reply. Yes the Optimax will tell you, but you have to take it to a tech so they can plug it in to give you the codes. My son has the boat on vacation. So far one day the alarm goes off and yesterday it never went off the hole day. Go figure.

I have an Etec not an Opti, so this may be a silly question. Does the Opti tell you what the alarm is? No oil, low oil, high temperature??? For me this is the first thing to understand. If the alarm is high temperature it is an issue with your thermostat, pump, gasket etc. It the alarm is low oil you either have low oil or a bad sensor. If the alarm is no oil, time to check the injection pump. Also, sounds like your mechanic is throwing darts at a board and hoping one of them sticks. He should be able to tell you what the alarm is, and what he thinks the most likely cause is. Odd to me that he initially suspects your water pump, then moves onto high RPM. I would imagine the Opti has a rev limiter. I know my Etec does. If someone put the wrong prop on the motor, the motor will cut out at 6300 RPM. I gotta believe the Opti is similar in that regard. For most of the new "smart motors" you couldn't blow them up if you tried. If the motor gets too hot it limits the RPM, if it is still overheating it shuts the motor down. I would politely explain your frustration to your mechanic and ask him for the alarm history. He should be able to get this by plugging his laptop into your motor. Once he tells you what is wrong, ask him for a repair estimate. Before you give him approval to move forward, ask him what his policy is if his "fix" does not correct the problem. From my perspective, if he diagnoses part "A" as being faulty and he replaces it, and you still have the same issue, part "A" was obviously not the problem, and he should credit that dollar amount toward his next guess.

I'm having a problem with a 2005 90-hp merc Optimax. The motor runs great but I have a alarm that keeps going off. The 1st thing I did was take to a dealer and they checked it out. They asked me if I had the water pump replaced and I said no, so they replaced it. they reset the codes. I took it out and it did not go off so I thought it was taken care of. The next trip I took it started up again. So this spring I took it back in and they checked it out again and said there is nothing wrong except we had the rpm's over 5500. So they changed the plugs and reset the codes and charged me $200.00. We took the boat up north this weekend and the same thing, the alarm is going off again. But this time we made sure not exceed the RPM"s.I have noticed it will go off when I throttle down, some times it is continuous beep other times it is short beeps. Has anyone had a problem similar to this. It is very frustrating, I do not want to blow a engine. I was thinking it might have a bad sensor.

Well I talked to the outboard mechanic that usually works on my motor he said the same thing 95psi sounded low but that may be the cheap tester. I took the advice of another and rebuilt the fuel pump last Saturday and also added a can of seafoam. Had the boat out both Sat evening and Sunday morning and she ran fine knock on wood... so lets hope that's all it needed. well till next time guys thanks for all the input actually lets hope there isn't a next time lol.... thanks again guys..

I agree I think it has to be in the carb. I've never run gas with ethanol through this motor in the 3 years Ive had it. I normally add something in with each tankful when I mix the batch up, either Stabil or last time was Marvel Mystery Oil. That jug was getting kind of old though so probably not very effective anymore. I need to run some Seafoam through. Could help but I'm afraid it just plain needs to be tore apart and gone through and readjusted. Thanks for the feedback.

Part of the reason cars/trucks don't have as big an issue with the reformulated gas is because it gets used before it collects a lot of water... Important to use a treatment for your boats and other small engines... I use Stabil (or your choice) in the gas cans I use to fill their tanks At least that is what works for me

I totally agree that "reformulated" gas is a problem; especially with boat motors. It tends to attract water, unlike "HEAT" it does not get the water to burn through, just waters down the fuel. It gets bad fast, and gets worse faster. I had to replace my entire fuel system on my mower a few years ago BECAUSE of the crap gas. Car and truck engines can handle it, especially the newer ones built after the mandate; but smaller engines cannot. In fact many manufacturers will void your warrantee if you use crap gas. Since I have been only using real gas in it even my weed eater starts for me. I don't know where you guys live but the Road Ranger in East Troy has real gas (in regular only). It is more expensive because our tax $ do not subsidize real gas, only the crap stuff. But if you put it in your road vehicle you will find you get much better mileage. If you put it in your smaller motors you will find that they actually start and run for you. This is an issue I have been on for a long time; I think we need to pressure Madison to get rid of the crap gas mandate.