200 Yamaha Won't Run Right

[carrabellefish]

I just bought a 200 Salt water series yamaha today 1993 model oil inject. I put it in the water today with the boat I bought it on and it idles just fine until you push it a little to get onto plane then it just sputters and shakes and won't go above about 2000 rpm wide open,  I dunno what to do or think any suggestions?

[slippery73]

Bad gas, probably needs a carb job and perhaps a tank cleaning. Make sure your fuel vent doesn't get water splashed into it, might need a clamshell cover on it.

[MarshMarlowe196]

Sounds like your engine is in "slow mode".  Could be a few things causing this, seems the most common thing is overheating, which is normally signalled by some kind of alarm.  First thing I would check is your water pickup (is it clogged?), and then make sure your thermostats are opening up.  Bad gas is somewhat of a remote possibility, as it seems unlikely that bad gas would limit an engine to a certain low RPM.

[carrabellefish]

There is no alarm at all. The boat pee's fine on the hose so I don't no what it is. It will idle all day long but the minute I try and go over 1200 rpm it just shakes and coughs but don't cut off it almost seems like a limiter or govenor. The compression is 115-120 on all 6 cylinders.

[slippery73]

There is no alarm at all. The boat pee's fine on the hose so I don't no what it is. It will idle all day long but the minute I try and go over 1200 rpm it just shakes and coughs but don't cut off it almost seems like a limiter or govenor. The compression is 115-120 on all 6 cylinders.

Governor won't make an engine cough, shake or spit. I don't know of any outboards besides perhaps the new 4 strokes like the verado's that have a governor that shuts an engine down to certain rpm. Most just have an engine alarm, overheating shouldn't cause your engine to do any of the above either, unless you stuck a ring. You've got carb issues, as a result of bad fuel or just from sitting, could have gummed it up. Either way i'd change my fuel, add a racor filter, have the carbs looked at. I had the same issues with two different boats, don't bother doing the carbs if you don't get your tank drained, it will be a waste of money as the problem might be in the fuel. The ethanol really screws things up.

[MarshMarlowe196]

There is no alarm at all. The boat pee's fine on the hose so I don't no what it is. It will idle all day long but the minute I try and go over 1200 rpm it just shakes and coughs but don't cut off it almost seems like a limiter or govenor. The compression is 115-120 on all 6 cylinders.

Governor won't make an engine cough, shake or spit. I don't know of any outboards besides perhaps the new 4 strokes like the verado's that have a governor that shuts an engine down to certain rpm. Most just have an engine alarm, overheating shouldn't cause your engine to do any of the above either, unless you stuck a ring. You've got carb issues, as a result of bad fuel or just from sitting, could have gummed it up. Either way i'd change my fuel, add a racor filter, have the carbs looked at. I had the same issues with two different boats, don't bother doing the carbs if you don't get your tank drained, it will be a waste of money as the problem might be in the fuel. The ethanol really screws things up.

Those year model Yamaha's did have a Governor of sorts- it's actually referred to as "Slow Mode".  It's a feature on the engine that protects the engine from damage by turning too many RPM's in a situation where it is overheating or having some kind of issue with oil, or something else.  It allows you to get back to the hill slowly w/o ruining your engine.  If it was a fuel/carb issue, it would most likely be surging and running rough at all RPM's, not just staying in a certain low RPM range.  The fact that it feels governed is most likely because it is being governed, in a way.  Your alarm should be sounding, but there's a good possibility that the wiring running to the alarm, or the alarm itself, may be fouled or malfunctioning.  Oil delivery is another common cause of "Slow Mode" in oil injected Yammer Hammers.  Check for clogs somewhere.  Also-  just because your motor is peeing does not mean your thermostats are opening up.  My old 90hp Jonny peed like a 3yr old in the bed, but the thermostats weren't opening due to corrosion.   A way that you could possibly tell if they're working-  Idle your engine with the cap off, place your hand on the block, does it feel too hot for idle temps??

[RickK]

When my engine oil reservoir gets low on my 230 the alarm sounds (which I can hardly hear while running) AND the motor idles down into this "slow mode" and won't go over 1500rpm.  Doesn't shake or cough though.  Well, maybe it shakes - afterall it's a '91 Yammy 250  

[MarshMarlowe196]

When my engine oil reservoir gets low on my 230 the alarm sounds (which I can hardly hear while running) AND the motor idles down into this "slow mode" and won't go over 1500rpm. Doesn't shake or cough though. Well, maybe it shakes - afterall it's a '91 Yammy 250

Very true Rick    .  It's hard to tell on an older model carbureted 2-stroker the difference between "coughing and sputtering" and a 2-stroker just being a typical 2 stroker.  The speed limiter/governor/"slow mode" feature on those engines is achieved by interrupting the firing sequence, so coughing and sputtering should definitely be associated with the engine being in "slow mode".

Of course, there's always the possibility that the engine is experiencing a different problem altogether, but given the symptoms, I'd bet my Suzuki that your engine is in slow mode.  Good news:  you don't have to pull/drain your tank.   Although, if you really want to be sure it's not bad gas, connect your engine to some known good gas (like a 6 gallon tank) then run it.

[slippery73]

When my engine oil reservoir gets low on my 230 the alarm sounds (which I can hardly hear while running) AND the motor idles down into this "slow mode" and won't go over 1500rpm. Doesn't shake or cough though. Well, maybe it shakes - afterall it's a '91 Yammy 250

Very true Rick    .  It's hard to tell on an older model carbureted 2-stroker the difference between "coughing and sputtering" and a 2-stroker just being a typical 2 stroker.  The speed limiter/governor/"slow mode" feature on those engines is achieved by interrupting the firing sequence, so coughing and sputtering should definitely be associated with the engine being in "slow mode".

Of course, there's always the possibility that the engine is experiencing a different problem altogether, but given the symptoms, I'd bet my Suzuki that your engine is in slow mode.  Good news:  you don't have to pull/drain your tank.   Although, if you really want to be sure it's not bad gas, connect your engine to some known good gas (like a 6 gallon tank) then run it.

If his carbs are gummed or plugged up connecting it to new gas wont do you any good. Your just going to have new gas flowing trough a clogged jet. I would recommend taking it to a reputable mechanic if your not familiar with it. Probably wouldn't hurt to have it gone through before you start using it.

[MarshMarlowe196]

When my engine oil reservoir gets low on my 230 the alarm sounds (which I can hardly hear while running) AND the motor idles down into this "slow mode" and won't go over 1500rpm. Doesn't shake or cough though. Well, maybe it shakes - afterall it's a '91 Yammy 250

Very true Rick    .  It's hard to tell on an older model carbureted 2-stroker the difference between "coughing and sputtering" and a 2-stroker just being a typical 2 stroker.  The speed limiter/governor/"slow mode" feature on those engines is achieved by interrupting the firing sequence, so coughing and sputtering should definitely be associated with the engine being in "slow mode".

Of course, there's always the possibility that the engine is experiencing a different problem altogether, but given the symptoms, I'd bet my Suzuki that your engine is in slow mode.  Good news:  you don't have to pull/drain your tank.   Although, if you really want to be sure it's not bad gas, connect your engine to some known good gas (like a 6 gallon tank) then run it.

If his carbs are gummed or plugged up connecting it to new gas wont do you any good. Your just going to have new gas flowing trough a clogged jet. I would recommend taking it to a reputable mechanic if your not familiar with it. Probably wouldn't hurt to have it gone through before you start using it.

If the problem went away after connecting it to good gas, then at that point, at least you'd know for sure that it was bad gas.  If it doesn't, then yes, it could still be clogged carbs/jets caused by bad gas/lack of use.  Just something cheap and easy to try on your own that could possibly save you a little $$.  Although, it's probably pointless to try this seeing as how the engine runs fine up until 1200-1500 RPM's, and if it was bad gas or clogged carbs/jets, you'd almost assuredly have a rough running engine at all RPM's, including idle.  

I agree though-  you'll probably have to take it to a mechanic to diagnose the reason for the probable "slow mode" if you're not familiar with the engine.

[DOCREED]

And then, it could be the stator..

[Boatdood]

The problem with diagnosing a problem online is that all too often some of the story is missing. It's nothing like actually hearing the engine run and being able to lay hands on it, therefore it's all pretty much educated guessing, with a short supply on education. What we have here is any engine that runs fairly smooth up to a distinct RPM of 2000. Carbs do have high and low speed circuits and some even have mid range circuits, but the transition from one circuit to another is something that takes place in a RPM range rather than like flipping a switch. Because of this I wouldn't guess carbs. A stator as mentioned by Docreed would be a fair guess if the engine were a Merc, but it's a Yamaha. Their stator works from one end of the range to the other unlike Merc's which have a two stage stator. A slow mode is something that is built into an engine's electronics as a self protect feature. It has been used routinely on larger engines from the big three for years starting back in the late '80's. It generally works by interupting the fire if the engine tries to go over a preset RPM range, usually around 2000. Below that everything is normal, except of course whatever caused it to go into the slow mode in the first place. The fact that no alarm accompanies the symptom may mean a couple of things. The first could be that it's not slow at all, but something else. The second is that not only is the engine having a problem, but the alarm's messed up too. And yet another possibility is that nothing at all is wrong with the engine but some sensor thinks something is wrong.

Good luck with it.

[lynnstrick01]

Easy and cheap stuff 1st, My 250 yamaha recently gave us same problems after sitting for almost a year, it was in fact water/condensation in the fuel.   1st you should have a water/fuel seperator, drain the water or  put in a new filter,  check your spark plugs, could have one or more fouled,  try it with good new clean gas as previously suggested, if all this doesnt help then you can go to carbs...This is where you have to make a decision,  if you are mechanically inclined carbs are not a huge job, just tedious, you just have to be VERY careful with them, I think with this model you will not be able to remove the carbs, you will have to work with them while still attached. You can easily mess up if you dont pay attention to exactly what you are doing every second.

 Buy a good repair Manual for your motor, read the section on carbs, if you are not totally comfortable with it, take it to a mechanic.  You can save $$ doing mechanical repairs yourself but if you mess up it can cost more in the long run than if you had just taken it to the mechanic to begin with. (there are some TINY parts that can be dropped and lost, which could be a HUGE expense)

The hubby is pretty mechanical and we have a marine mechanic who is willing to let us pick his brain for free, So we can usually combine the knowledge the hubby already has with a little info from the mechanic and do most repairs ourselves. We do this not only to save $$ but to limit downtime. But not all marine mechanics are that helpful,  ONLY YOU can make the decision if this is something you can deal with yourself or if you need a mechanic.