New boat engine issues

S

Scrooge

New Member
Jun 11, 2019
13
Boat Info
2019 310 SLX
Engines
Twin
So I thought I'd throw this out there for anyone who's interested or who might have some insight. Picked up my new 310 SLX a few weeks back - beautiful boat! First weekend out with the family, lost an engine. Ran great for a while, then just wouldn't restart. Reported it, and they couldn't find anything wrong.

Second weekend out, lost the same engine again... reported it and they were finally able to replicate it. It's only one engine, the other is fine. Initial reports are it's a vapor lock issue.

Did some digging and it seems sometimes people have this problem, but in my opinion this boat has 15 hours on it and has barely been run at all (definitely not more than 3500 rpms) and there shouldn't be this kind of issue.

Dealer is trying to get in touch with mercury on this. anyone else had anything like this on a new boat. It's become very concerning for me...
 
Scrooge said:
So I thought I'd throw this out there for anyone who's interested or who might have some insight. Picked up my new 310 SLX a few weeks back - beautiful boat! First weekend out with the family, lost an engine. Ran great for a while, then just wouldn't restart. Reported it, and they couldn't find anything wrong.

Second weekend out, lost the same engine again... reported it and they were finally able to replicate it. It's only one engine, the other is fine. Initial reports are it's a vapor lock issue.

Did some digging and it seems sometimes people have this problem, but in my opinion this boat has 15 hours on it and has barely been run at all (definitely not more than 3500 rpms) and there shouldn't be this kind of issue.

Dealer is trying to get in touch with mercury on this. anyone else had anything like this on a new boat. It's become very concerning for me...
Click to expand...

If it really is a vapor lock issue then make sure nothing made a nest in the fuel tank vent blocking it. That has shown to be a problem before.

-Kevin
 
Scrooge said:
So I thought I'd throw this out there for anyone who's interested or who might have some insight. Picked up my new 310 SLX a few weeks back - beautiful boat! First weekend out with the family, lost an engine. Ran great for a while, then just wouldn't restart. Reported it, and they couldn't find anything wrong.

Second weekend out, lost the same engine again... reported it and they were finally able to replicate it. It's only one engine, the other is fine. Initial reports are it's a vapor lock issue.

Did some digging and it seems sometimes people have this problem, but in my opinion this boat has 15 hours on it and has barely been run at all (definitely not more than 3500 rpms) and there shouldn't be this kind of issue.

Dealer is trying to get in touch with mercury on this. anyone else had anything like this on a new boat. It's become very concerning for me...
Click to expand...

I'd do next to nothing to troubleshoot on a new boat with the kind of pricetag it carries, dealer should fix all....BUT you could open the hatch next time it happens and see if it'll restart once it cools down. If it does, their assessment of vapor lock might be correct.
 
Thanks for the info - that was my sentiment exactly. 15 hours on an engine and this shouldn't be happening (and it's not happening on the other engine). Just to be thorough, last weekend I left the hatch up for 4-5 hours and it still wouldn't start. It cranks, but won't fire. Thankfully they were able to replicate the issue. It did finally start the next day after it fully cooled down.
 
Vapor lock is easy enough to be confirmed, you open the shrader valve and see what comes out...gas or vapor.

Is it the port engine ?
 
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I understand the frustration. Around here, the dealers are busy, and warranty or not, they can look at it in two months, after the season is over.
 
Scrooge said:
So I thought I'd throw this out there for anyone who's interested or who might have some insight. Picked up my new 310 SLX a few weeks back - beautiful boat! First weekend out with the family, lost an engine. Ran great for a while, then just wouldn't restart. Reported it, and they couldn't find anything wrong.

Second weekend out, lost the same engine again... reported it and they were finally able to replicate it. It's only one engine, the other is fine. Initial reports are it's a vapor lock issue.

Did some digging and it seems sometimes people have this problem, but in my opinion this boat has 15 hours on it and has barely been run at all (definitely not more than 3500 rpms) and there shouldn't be this kind of issue.

Dealer is trying to get in touch with mercury on this. anyone else had anything like this on a new boat. It's become very concerning for me...
Click to expand...


I will disagree with your esteemed mechanics. If a Vapor Lock issue existed on a new engine......why doesn't the other engine have the same problem?

What they need to do is some real diagnostics: fuel pressure, codes and voltage checks. It could a number of things and calling Mercruiser won't solve any of them.
 
It's the starboard engine. Port engine starts and runs just fine - good thing too cause it got my family home twice.

I'm waiting on the full details of what's been done so far, but I at least know they have checked codes and pressure and maybe a couple other things and all is "normal."
 
The problem is based on this forum.....I just don't have a lot of confidence in marine mechanics unless they solve problems.

In your case, they should know since they were unable to restart the engine...whether or not it is a fuel system issue. How, because when it cranks and doesn't fire....you shoot carb cleaner or starting fluid into the air intake to see if it starts for a few seconds. Instantly you know whether you are chasing a fuel system issue or it is an electrical issue. It is unlikely to be both.

The ECM starts the fuel pump, fires the injectors and triggers the spark. If you don't have any codes.....something is happening that the ECM can't sense.

On a new boat....there shouldn't be mysteries or excuses.

I'm curious what they tell you next.
 
PlayDate said:
The problem is based on this forum.....I just don't have a lot of confidence in marine mechanics unless they solve problems.

In your case, they should know since they were unable to restart the engine...whether or not it is a fuel system issue. How, because when it cranks and doesn't fire....you shoot carb cleaner or starting fluid into the air intake to see if it starts for a few seconds. Instantly you know whether you are chasing a fuel system issue or it is an electrical issue. It is unlikely to be both.

The ECM starts the fuel pump, fires the injectors and triggers the spark. If you don't have any codes.....something is happening that the ECM can't sense.

On a new boat....there shouldn't be mysteries or excuses.

I'm curious what they tell you next.
Click to expand...
My father had problems with his new van, it would run a little and quit, run a little and quit. He was out of town, end of the day on a Friday. Pulled into a GM dealer and they put a couple mechanics on it. They found no codes and couldn't figure it out and they were stumped. After an hour or so, being late on a Friday they wanted to give up on the mystery and go home.

When my father saw their approach to things, which was to do the same things over and over, he suggest lets verify spark and fuel the 'old fashion way'. They ignored the old fart until finally one guy gave in. In just a couple minutes they found out it was a fuel problem, verified by some taps on the gas tank. The new van had a faulty fuel gauge and it was out of gas.
 
PlayDate said:
The problem is based on this forum.....I just don't have a lot of confidence in marine mechanics unless they solve problems.

In your case, they should know since they were unable to restart the engine...whether or not it is a fuel system issue. How, because when it cranks and doesn't fire....you shoot carb cleaner or starting fluid into the air intake to see if it starts for a few seconds. Instantly you know whether you are chasing a fuel system issue or it is an electrical issue. It is unlikely to be both.

The ECM starts the fuel pump, fires the injectors and triggers the spark. If you don't have any codes.....something is happening that the ECM can't sense.

On a new boat....there shouldn't be mysteries or excuses.

I'm curious what they tell you next.
Click to expand...
Not sure what his plenum looks like, but shooting carb cleaner in my old 99 plenum, the fuel, would never get there. Too far to go, made for air not fuel
 
I just hate to hear that a person who bought a brand new Sea Ray is having a problem like this. It is a story that never goes away and makes a new owner suspicious as to what is going wrong next.

Put the mechanics on it and get the owner back to enjoying his NEW boat.
 
Agree 100% , hope they don't jerk him around. If they do, I'd be in there myself to finish the season.
 
If, and I mean IF, I ever buy a new boat I will get it surveyed and shake down ran before I took delivery.

I’m reading more and more about problems w brand new boats.
 
PlayDate said:
I just hate to hear that a person who bought a brand new Sea Ray is having a problem like this. It is a story that never goes away and makes a new owner suspicious as to what is going wrong next.

Put the mechanics on it and get the owner back to enjoying his NEW boat.
Click to expand...
Right on! I hope they do right by you, and fast! If that happened to me, on my brand new boat first two trips out, my wife would have a “for sale” sign on it the following day. Good luck.
 
Hi Guys, well still don't know the cause. They have been able to replicate it and at the instruction of Mercury & SeaRay they have taken another 310 SLX, that's new on their dock, and installed temp gauges in the engine compartment and then put it through the paces to see what the readings are in the bilge and near the fuel rails at various RPMs and speeds. That info has been relayed to Mercury and we're awaiting a response.

I don't have to tell you I'm pretty pi$$ed about the whole thing. It just doesn't make any sense that one engine doesn't have any issues and one does. No codes, no voltage issues - nothing. Oh, and here's one more thing... there are two other 310 SLXs that they are dealing with the same issue on with other owners on the lake. All fuel is non-ethanol, FYI.

I'm trying to keep my cool I don't believe anger really helps, but that's not going to last much longer. I really have no idea what kind of recourse I have with this, but if this isn't fixed very, very soon or if they simply tell me "we don't know," I'll probably be demanding they buy it back.

Boat has 18 hours on it. Ridiculous.
 
Scrooge said:
Hi Guys, well still don't know the cause. They have been able to replicate it and at the instruction of Mercury & SeaRay they have taken another 310 SLX, that's new on their dock, and installed temp gauges in the engine compartment and then put it through the paces to see what the readings are in the bilge and near the fuel rails at various RPMs and speeds. That info has been relayed to Mercury and we're awaiting a response.

I don't have to tell you I'm pretty pi$$ed about the whole thing. It just doesn't make any sense that one engine doesn't have any issues and one does. No codes, no voltage issues - nothing. Oh, and here's one more thing... there are two other 310 SLXs that they are dealing with the same issue on with other owners on the lake. All fuel is non-ethanol, FYI.

I'm trying to keep my cool I don't believe anger really helps, but that's not going to last much longer. I really have no idea what kind of recourse I have with this, but if this isn't fixed very, very soon or if they simply tell me "we don't know," I'll probably be demanding they buy it back.

Boat has 18 hours on it. Ridiculous.
Click to expand...

I think it is fair to say that all of us feel bad that you are going through this with a new boat.

I certainly am old school about chasing problems and if they believe that it is vapor lock...you place a couple of ice bags around the pump and line and see if it makes a difference. If it does.....something is off with the ventilation design (very disappointing) which appears why they are taking temperature measurements on other boats. If it doesn't.....they are chasing the wrong problem.

In regards to recourse.....that will come down to the "lemon laws" in your State.
 
Scrooge said:
Hi Guys, well still don't know the cause. They have been able to replicate it and at the instruction of Mercury & SeaRay they have taken another 310 SLX, that's new on their dock, and installed temp gauges in the engine compartment and then put it through the paces to see what the readings are in the bilge and near the fuel rails at various RPMs and speeds. That info has been relayed to Mercury and we're awaiting a response.

I don't have to tell you I'm pretty pi$$ed about the whole thing. It just doesn't make any sense that one engine doesn't have any issues and one does. No codes, no voltage issues - nothing. Oh, and here's one more thing... there are two other 310 SLXs that they are dealing with the same issue on with other owners on the lake. All fuel is non-ethanol, FYI.

I'm trying to keep my cool I don't believe anger really helps, but that's not going to last much longer. I really have no idea what kind of recourse I have with this, but if this isn't fixed very, very soon or if they simply tell me "we don't know," I'll probably be demanding they buy it back.

Boat has 18 hours on it. Ridiculous.
Click to expand...

Vapor lock is caused by heat - basically the fuel sitting in a hot fuel line vaporizes and cannot be pumps - a fuel pump can only pump liquid, not a vaporized fuel / air mixture. So yes, this can absolutely happen on one engine and not the other. It does not mean anything is wrong with that engine, it is in the location and routing of the fuel lines that are allowing the line feeding that engine to get hot and vaporize the fuel after you have shut the engine down. If this is not happening AFTER the engine has been run and then shutdown for a period of time, then it is NOT vapor lock. Vapor lock doesn't happen on a running engine - only on a hot engine that is shut down, fuel vaporizes in the lines and engine won't restart until it cools down. The Cool Fuel system is an attempt at minimizing vapor lock, but it does not always work. Usually re-routing or insulating the the fuel line is the fix. Had a friend some years ago with a 2001 340da that one engine vapor locked all the time - he would take his transom shower and hose down the fuel line and cool fuel with cold fresh water and that was get it running - they finally made some changes to the fuel line routing and that fixed his problem.

Here is some good info about vapor lock: https://www.perfprotech.com/blog/articles/mercruiser-vapor-lock
 
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@BillK2632 Thanks for the info. I've learned quite a lot about it over the last few weeks.

SR themselves have now reached out to me to try and smooth things over and according to SR, Mercury is supposedly sending a tech here to survey the situation. More "hurry up and wait..." I'll fill everyone in as more info becomes available.

Thanks for everyone's input.
 


Chill your lines down





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