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Major engine problem

Seadeals

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I get an error on your video. Sounds like nice work though. Look, the slime thing is not some mystery “love jelly” in your fuel and on your tank. Water sitting in enclosed compartments just gets slimey. I had both the fuel bay plug and the forward engine plug pulled after the boat was in the rain for a few days and the water that remained below the drain opening turned slimey after a week.

Water in the tank can cause stumbling. Whether you have a lot or a little is hard to say; but it probably isn’t the whole issue and by doing what you are doing, you eliminate one variable in what seems to be a complex equation, so that is progress any way you slice it.

Don’t give up your full speed sunset runs. We both know what they are worth. I just made one myself tonight but gifted the glassy sunset to four other grateful passengers. The boat is meant to do that.
 

Seadeals

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One of my all-time favorites...Lake Burton, GA.
EA1E465E-6F04-4E4D-8DD0-C495796618B4.jpeg
C13C0F7A-348C-4FFE-868F-7DEA9434EC50.jpeg
 

tahmad575

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@Seadeals that's a wicked sunset and you prove a great point, nothings better than just flying over the water without a worry in the world

Perhaps the video had not fully uploaded yet anyways it took longer than anticipated to pull all of the injectors and clean them meticulously, they were clogged a bit in the beginning but after some pressure with the carb cleaner can the stream was better and more atomized

I pulled out a 2 litre soda bottle worth from each fuel line by attaching a positive and negative lead directly to the fuel pump connector (so that I don't have to crank the engine) and right away I could see droplets falling down and collecting in the bottom of the bottles. I'll leave it over night and see how much is in there. Before I call it a night I'm going to try to drain the oil completely from both engines and get to work on disassembling the ecu boxes

No one showed up to crank the engines while I check for pulse on the fuel injector wires with a 12v led test light so I'll try again for that tomorrow night
 

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bronze_10

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@bronze_10 how come your ecu's kept going bad? Was it that they were getting wet?
@Beachbummer from the starboard engine I have been able to get out 3 quarts with the suction method, I'm going to do a complete drain by taking out the drain plug to gauge exactly how much was in there. I have not yet done the port but I will get back to you on that one as well
There is a long thread on here somewhere but basically I was caught at a gas station fueling up in Florida when a monsoon came. The roof was damaged and was running water off the roof like Niagra falls straight over my engine hatch. The bilge pump came on in the gas station parking lot. Both bilge pumps! This time it was a failed ecu repair not water!
 

bronze_10

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@bronze_10 what test in the yds told you that your ecu was the problem?
yds told me an injector was not working by using the buzz test feature. I already had the ecu repaired last year so I incorrectly assumed the issue was with the injector. After removing the entire throttle body and testing the injectors I found all injectors were fine. So back to the ecu. I just sent it back off and they verified the issue was with their repair
 

Gym

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I would only drain or filter your fuel tank if the mysterious material is anything but water. As I mentioned if this material has any viscosity or density greater than water this issue may repeat itself. It's possible you have also pulled some of this into your fuel pump intakes. I would first get a sample from the fuel you have drawn out.
 

tahmad575

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POSSIBLE ECU MALFUNCTIONS

Here are my findings:

FUEL:
The very first starboard 16oz sample I pulled out from the fuel line had in fact a small amount of water in it. The port 16oz sample had nothing inside, the next day to confirm I took out 2 litre soda bottles worth of fuel and after sitting for 24+ hours there has been no discovery of water or phase separation. The boat has been level on a trailer. I guess the marine 360 needed some time to get to work? Also I am assuming the majority of water had been used up by the engines while I was trying to start it on the water the day I noticed problems and the second day when I was running it a few rpms above idle in order to gauge what was wrong. When I arrived to my warehouse outside I started up the engines to take out the water in the coolant lines and pumps before I take it inside and they fired right up and didn't die on idle.
I'm going to try to take out the fuel pumps and seal them up because I believe that's where the water got in.
I ordered 2 water fuel seperators and will install them tonight for each engine


FUEL INJECTORS:
They were pretty clogged but once I cleaned them with carb/air intake cleaner the spray was much more atomized. Resistance check and ohm readings were at 12.3, so within the 11.5-12.5 ohm threshold as stated in the service manual. For all of the connectors there was 12v power and ground when the key is turned to the on position, as well as barely noticeable flickering of my led test light when the engine was being cranked.

SPARK PLUGS:
I removed spark plugs from both engines and they looked fine because I put them in 3 months ago and they are the ngk irridiums although there was signs of a little bit of rust on the threads and the coil packs are a little rusty as well. I re-applied anti seize and dielectric grease, while reinstalling the coil pack I tightened the screw too tight and it broke while inside the head..😑

MOTOR OIL:
I took out 2 water bottle samples the day this happened and it's been about 48 hours, the port sample is dark brown and the starboard is darker brown with a slight hue of green and a slight odor of fuel. I drained all the oil from the engines first with a hand syphon pump then by taking out the drain plug behind and below the engine, such a pain to get to that drain plug bolt with no mirror and only a smartphone camera but I drained it and ofcourse I managed to spill some in the bilge. Collected a little over 4 quarts total from each engine. New oil added is Mobil one 10w-40 with mobile one M1-110 filters. I have added only 3 quarts right now and will probably crank the engines to cycle the oil and slowly add half a quart more until the oil level is at the E mark when cold so that I can start the engines to see if my repairs have worked.

ECU'S:
So when I opened up the boxes for the ECU's there was no visible pool of water or rust but there was a very thin film of moisture on the rubber seal that holds the ECU box together, this film of water was present in both boxes. I'm assuming there was moisture buildup inside the ECU box and since the boat has been sitting in my warehouse while it's 80° out the moisture was finding it's way out. I unplugged the ECU and the connection was fine, no signs of water in either ECU connectors. To be honest the inside of the ECU boxes looked brand new especially the connections, as a matter of fact the inside of the ECU boxes is hands down the cleanest part on the boat I've seen. In any case I took the ECU's home with me and I'm going to attempt to dry them in case any moisture got in by keeping them in a container full of silica gel desiccant packets to dry them out for a day or two.

Hopefully these repairs I'm making will resolve the issue, I will make an update in a day or two once I put everything back together
I am grateful for everyone who took the time out of their day to help and give me advice, any more suggestions or tips would be appreciated 👍
 

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Gym

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Wow. great update. It would have taken me a week to do all you did in a day. Then another week to write it up.

A couple of observations...You mentioned replacing the fuel pump gaskets believing that may have caused water to leak into your tank. Whereas water is 784 times more dense than air ( in this case fuel fumes) meaning if water could get in to your tank fumes were 784 times more likely to escape. I'm wondering if you were smelling fumes anywhere, especially in the engine compartment?

Also, I did notice a little rust on the threads of your #3 spark plugs on the first pic you posted of your plugs. I'm glad you're going to use antiseize. Seeing the traces of rust on the outside of the coil boot indicates you are getting water fairly high up in your engine compartment. That may have some relationship to the trace moisture you found in your ECUs.

Good job. I hope you're back on the water soon.
 

Beachbummer

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The previous cases of ECU damage causing the injector to receive signal to remain open the whole time has generally resulted in thin oil, as well as a lot of extra oil present in the engine, per the recent history of the board that I have read. Hopefully that means no ECU problems for you.
 

Papa

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I'm late to this party, but another thing to change since your elbow deep into this is the fuel lines. If they are original to the boat they will not be the lines for E10 fuel. I had this same problem with my 05 SX230. Mine was so bad I had to have the injectors put in an ultra sound tank over night. I changed fuel line from the tank to the engines and put in a water separator filter. After getting everything cleaned and back together it is still running like the day I bought it.
Papa
 

AmesJainchill

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Thanks scuba_ref
I was thinking the same thing because this gas station is a new one I went to, it was closer to the lake by 10 minutes and I figured since it's a BP gas station it should be good. Usually I've been going to the same delta, any suggestions on a GOOD gas station?
I've used pure-gas.org to find places with E0 nearest to where I'm boating. Some stations haven't been updated in a while on the site and some are more recent, but at least it gives me some places to call and confirm.
 

CRESTAPRE

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Something to look into is the 'clear bowl' fuel filters. I've been told that those are not to be installed in an enclosed engine bay, more for outboard engine use. The clear glass/plastic bowl could break pouring fuel into the engine compartment. I've installed the Racor 110 fuel filters with an alum bowl. I'm under the impression that this my also be a CG regulation. Just my two cents.
 

Beachbummer

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It's about "fire proofness" I think the engine area is supposed to withstand a fire for X time before the fuel catches. The plastic and glass bowls for gas fuel do not meet that rating. It's OK with Diesel since it does not ignite until it reaches much much higher temperatures. Same reason for A rated fuel line vs B rated fuel line.
 

CRESTAPRE

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I just mentioned it because it appears that he has purchased clear bowl fuel filters. Whatever the reason, it could be a situation. Be safe out there.
 

buckbuck

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@tahmad575
Help me understand the rust on the coils. Where is it originating? I thought the valve cover and head were all aluminum.
 

tahmad575

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@Gym Yeah so the day that this all happened I don't recall smelling any fuel smell in the engine bay but come to think of it previous times when I open the fuel tank hatch after the boat sitting at the marina all night there were times when there was a strong odor of fuel, also a very slight odor in the engine bay. But again I have only smelt this when I first arrive to the boat and open the hoods to check for water accumulation in the bilge, after that the smell dissipates. hopefully the fuel pump gaskets are the issue.

@Beachbummer I hope so too man, I never watched the fireworks while on the water but I really have been looking forward to enjoying Fourth of July on the Hudson river this year with my family. Its a only a week away so I've been working till 5am trying to get all this work done.

@Papa Thanks for the tip, that hadn't even crossed my mind but since you mention it I'm going to go to home depot and grab some rubber hose tonight, Might as well since I'll be installing those fuel filters. Would any rubber hose work? Or do I need something special?

@AmesJainchill Awesome thanks for that link I'm going to look for gas stations along my route or near the lake.

@CRESTAPRE and @Beachbummer You both have solid points and potentially just saved my whole boat, I messed up and didn't think about that and the last thing I want is a fire.. @Scuba_ref suggested Racor filters with a metal bowl but they were $100 over my budget so I figured I could get away with these after reading good reviews. I am going to install the ones I ordered and before I start the engines I'm going to find metal bowls that will screw on to the filters I have ordered. Hopefully I can get them delivered by Sunday (shout out 2 day amazon prime shipping) Or I'll look for maybe a plumbing supply store that carries a metal bowl that'll fit, I'm assuming its a standard screw on size?

@buckbuck I am assuming since my bilge always has about an inch of water in it (too low for the bilge pump to activate) the moisture builds up? Idk where the water comes in since I recently reinstalled the drain plug assembly because I accidentally broke it off when taking out my drain plug. I know its a good seal I made new holes and used 3M 5200 and let it cure for 7 days, perhaps the water is coming in from the jet pump main seals? my friend who owns a waverunner suggested that
 

Scuba_ref

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You will want to get actual fuel line hose from an auto parts store. That is where I got mine when I installed the filters!
 

Beachbummer

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Any local marine supply store or similar will have the spin on metal fuel filter canister. Academy carries them, and they are available on Amazon too. I have used the Sierra brand with success.
 

tahmad575

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Unfortunately I think I have a fuel tank leak? I also believe that there was definitely more motor oil than anticipated. I drained the oil by a hand syphon pump then took out the oil drain plug, even after draining there was a quart extra in the engines so about 5-6quarts total... I had bought the boat and when I did it had fresh oil and I figured that would be the least of my worries even though I constantly checked the level.
Never heard this before but after putting in 2 quarts of oil to get the oil level to the L line on the dipstick there's a gargling sound from the starboard engine when I crank the engine, like oil coming up to the throttle body. This doesn't happen in the port
Put everything back and when I opened my compartment under the gauges there was an overwhelming fuel odor. I then decided to open the main ski locker and that as well had a strong smell of gasoline then I opened the passenger side compartment and that smelt like fuel as well.

what are the necessary steps in order to locate a leak or the reason why it smells like fuel so much? Previously those compartments had never smelled like that before

Also I installed the new fuel filters, Everytime I pressurize with fuel the inlet and outlet fittings leak a couple drops of fuel. All 4 fittings on both filters. I inspected the aluminum housing and it doesn't appear to be cracked, I tightened them pretty good and when it started leaking I tightened them even more, still no signs of fracture in the housing assembly but it's definitely leaking only when I pressurize the system. It appears to be leaking out from the threads but that can't be possible because they're tightened, only other place would be the filter and I tightened that really well and even applied a thin coat of motor oil to the rubber seal on the filter

I'm also concerned that since these filters leak when cranking the engine, if I were to go let's say full throttle would the fuel pressure be increased?? Or would the fuel injectors just fire more rapidly?? If the pressure is increased I'm really not sure if I want to keep these filters because I think that's a catastrophic fire just waiting to happen
Update: after reading a 1 star review on the filter there's a dude who has the same leak and it's because of a missing O ring that never came with the kit so I never thought it would be an issue. There's the regular seal but I attached a picture of where an o ring should go inside the crimped lip of the filter. So I guess I'll go to an auto parts store and pick up one with that size and see if it'll stop leaking
 

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