Update #2 Trouble Shooting Help: Neither Engine Stays Running.

[Chr2004]

Update [HASH=460]#2:[/HASH]
We isolated the <exhaust> leak to the compartment aft of the engine compartment. It was obvious once we opened the clean out port cover where the exhaust was coming from. The resonator had melted. Pictures attached. The last people to work on the port side exhaust was the dealer.

Update: Thanks for all of the input!
We emptied the entire tank, cleaned it out, pulled port side injectors and cleaned them. We filled the tank with two bottles of sea foam Marine and 20 gallons of Shell 87 pump. Same exact problem. Ran in the water at idle for 30 mins smooth with no issue then 2K rpm no issues then 3.5K both engines struggle at the same time. Starboard dies after 15 seconds, port gives me about 30 seconds. Neither will re start unless you wait for about 15 mins. We are simply out of ideas.

Hello!
Going on 4 years of reliable boating with our 2011 242LS. For the first time the engines are giving me trouble. I changed the spark plugs and tested each engine for at least 5 minutes each on land. In the water (mom's only mothers day request was to go boating) port started fine and starboard had issues. Got it started and after about 5 minutes of idle speed both shut down. I tried re-start with no success. After about 10 minutes of letting them sit they both started with some hesitation and ran for about 5 minutes to get us back to the ramp. I let them run at the dock for about 5 minutes and decided to do another test at 2K rpm and below around the Marina. They both bogged at shutdown at the same time again. Looking to troubleshoot today.

I believe last fill up was ethanol free Murphy with Stabil storage about 8 months ago. I leave tank topped off.

Any insight would be greatly appreciated!!

 

[lazergeek]

Sounds like bad gas to me. Mine did the exact same thing last year when some asshat put water in my tank when leaving at a paid dock overnight. I ended up pulling the fuel pump and pumping all the gas out the hole.

 

[Chr2004]

Thanks a lot for the response!
I can't see any other logical explanation. Think Sea Foam or some other additive might help?

 

[Cobra Jet Steering LLC]

Both engines doing the same thing is stale fuel in my book also tell your mother we are really sorry she could not go on the boat for mothers day and make it up to her it is great to have a mother and even better that she likes boating, when you get my age and you have already buried your parents, watched your children grow up and hit their 40's watched your grand children grow up and go off to collage or the military you suddenly realize how fast time flies and what we take for granted. I remember camping for 2 weeks every JUNE as soon as the school closed for summer vacation and having the kids and grand kids out on the island along with my parents enjoying the water and each others company . fix the boat and enjoy the important things in life.

 

[lazergeek]

Thanks a lot for the response!
I can't see any other logical explanation. Think Sea Foam or some other additive might help?

If your 100% sure the entire tank was ethenol free you can probably just run it through a Mr Funnel to separate the contaminats out. If there was any ethonal gas then all the ethonal separated with the water and it's not worth the effort at that point as your trying to filter out 10% of your tank. I was on my 5th pass through the filter and still getting separation.

 

[Cobra Jet Steering LLC]

Remember these boats have open fuel tanks, the symptoms could also be water in the tank, take a hose to the very lowest point of the fuel tank and siphon a gallon of fuel out placing it in a glass jug, let it sit and look for water settling at the bottom of the jug. My guess is the fuel went sour though.

 

[lazergeek]

Once you have the tank refilled with clean gas, remove the fuel lines from the fuel rail and pump the remaining old gas by trying to start. I pulled a out a gallon between both motors before it started running good again.

 

[Chr2004]

Thanks for the responses!
Instead of wasting time filtering (I’m sure a portion of the gas in the tank had ethanol) I’m leaning towards just pumping it all out. Any guides on the best way to get it out? Im not exactly sure how to pull the pump and get it out.

 

[Cobra Jet Steering LLC]

That may require a specialist since it could be very dangerous with all that fuel the thing that I keep thinking about is water in the bottom of the fuel tank when the boat sits the water settles to the bottom but when you run the boat the water gets mixed back into the fuel and the causes the problems A big water separator in the fuel line may be worth trying as well as siphoning the water out of the tank first if you angle the boat so the tank is leaning either forward or backward the water will settle in the lowest part then placing a plastic tube down to that part of the tank will quickly tell you if water is sitting there and you can get most of it out with the siphon into a 5 gallon can, then some fuel additive and octane booster may work it is what I would be doing. And I have had water in my tanks more that once. what makes me think this is the boat ran then stalled out then ran again etc totally bad fuel usually won't run so perhaps it is water. take the path of least re$i$tance first.

 

[lazergeek]

I have the FSH so it was an easy panel under the helm to get to the fuel sender. Not sure on the other models. I used an electric fuel pump to syphon out but still took a few hours for my 30 gallons in the tank. You could probably snake a hose down the fill tube to get the bulk out but you will want to get all you can before putting new gas back in

 

[Chr2004]

Update: Thanks for all of the input!
We emptied the entire tank, cleaned it out, pulled port side injectors and cleaned them. We filled the tank with two bottles of sea foam Marine and 20 gallons of Shell 87 pump. Same exact problem. Ran in the water at idle for 30 mins smooth with no issue then 2K rpm no issues then 3.5K both engines struggle at the same time. Starboard dies after 15 seconds, port gives me about 30 seconds. Neither will re start unless you wait for about 15 mins. We are simply out of ideas.

 

[lazergeek]

That sounds like a bad fuel pump, Since it runs fine at lower RPMs. The pump has to cool down before it will restart. I had a Ford explorer do that exact same thing one summer. New fuel pump fixed it.

 

[TeenGee]

Aren't there 2 fuel pumps?
Do you smell exhaust in the engine compartment?

https://jetboaters.net/threads/yamaha-210-fsh-with-exhaust-leak-took-forever-to-diagnose.35501/

 

[Neutron]

Aren't there 2 fuel pumps?
Do you smell exhaust in the engine compartment?

https://jetboaters.net/threads/yamaha-210-fsh-with-exhaust-leak-took-forever-to-diagnose.35501/

Had exhaust leak problem on one of my skis that caused this same problem

 

[Julian]

As others have said, did you block the air intakes for the engine compartment? Try running with the blower going or the engine compartment open.

One guy had an exhaust leak that smothered the engines. Other his insulating foam was laying on top of the engine.

 

[Chr2004]

Great theory gents. I’ll report back tomorrow!

 

[ripler]

This is why I miss this forum, the knowledge and experience is unmatched. The people on the MasterCraft forums are a bunch of arrogant pricks and tell you to take your boat to the dealer if you are having issues.

 

[Cobra Jet Steering LLC]

I am surprised that it was not the fuel. I also had a similar situation where there was some trash in the fuel tank and as the boat ran the trash collected on the fuel pickup in the tank and cut the engine down, after letting it sit a while the trash fell off the pickup and the engine ran fine but then repeated the same issue. I had to empty and open the tank and look inside to figure out what was causing the problem, I have had exhaust leaks but it only reduced the top end speed it did not kill the engine, you can inspect the hose clamps around the water boxes but you would be experiencing a lot of water in the hull as well. If the engines were seriously overfilled with oil it could be causing problems also if your gas tank vent is blocked by something it could cause this problem.

 

[Chr2004]

Interesting you mention that. There was one noticeable leak in the port exhaust which turned out to be a loose clamp. We tightened it still thinking the fuel had to be the problem. After we tightened it the engine still bogged down after 3.5K so there may be more
Leaks. Also the dealer was recently messing with the exhaust.

 

[Beachbummer]

This is probably not it, but can't hurt to open the fuel fill cap to allow air into the tank, in case your breather is bad/clogged and causing a vacuum in the tank. Could also be electric to the fuel pump? Good Luck keep us posted!