stuartsx5

That doesn't look good.

I just realized I failed to let everyone know what I found. Maybe help someone in the future. It's gonna be a long one. To begin with, I thought I had a fuel delivery problem so I changed out the High Pressure pump. Took it to the lake, ran worse. At this point I took it to a mechanic. He told me it wouldn't throw any codes because I wasn't getting an alarm. I mentioned that I didn't get the tone when I started it so I was curious if the alarm was working. He said some do give you a tone, some don't. He hooked it up to a fuel pressure gauge and said that the cheap pump I bought coupled with a bad fuel pressure regulator was pegging his gauge causing too much fuel in the cylinder. He sent me a link to OEM parts and I paid $800 for the parts and $400 for him to put them in. When he was done he mentioned that it didn't like to get on plane, which had never been an issue. When I picked it up, I put it on the water. It would plow water for almost a hundred yards then get on plane and start cutting out just like before. At this point, I have a friend who is a vehicle mechanic so he came over to see what he could do. We discovered that my fuel pressure was still too high. After some experimentation with fuel lines removed, we deduced that the pressure regulator wasn't getting any fuel. Took the vapor tank apart and discovered that when you put a pump in there and you don't get the outlet seal in right, it blocks the port to the regulator so you have unregulated fuel. Got that put back together correctly, tested that pressure was good and off to the lake. Same issue of cutting out. Brought it home and decided to pump out the gas, clean the tank and put in all new fuel lines. Found a Sta Byl bottle seal and a ball point pin in the tank. All new ethanol free gas, new pickup tube, and new fuel line. Off the the lake with my mechanic buddy, same issue, runs good then starts cutting out. He mentioned that it sounded more like a rev limiter cutting out cylinders than a fuel issue. This led to some research and finding the term guardian mode and what would cause a Merc to go into guardian mode. This is temperature and oil. I knew it wasn't getting hot so I started looking at oil and why I didn't get an alarm. Two issues. Alarm: Sometimes the annunciator goes bad on your alarms in a marine environment. So, I tested the annunciator and sure enough, it was bad. Replaced that and started getting the "All Good" beep on start up. Oil: If the small tank on the side of a Merc engine is not full, the motor will go into guardian mode and will not let you get above 3,000 RPM. I had oil in that tank but it was only half full. I discovered that the small tank on the engine is kept full by crankcase pressure on the storage tank in the bilge. The tank is pressurized by a small amount, under 10 psi. The oil goes through a tube that has a screen on it in that bulk tank. Over time, 2 cycle engine oil can gel on that screen, reducing the flow. Took it apart and sure enough, the oil was gelled on the screen. Cleaned it off, dumped all the oil and refilled the storage tank. Reduced my air compressor to like 5 psi, hooked it up to the storage tank and filled the small tank full. Result: Took the boat to Pomme, ran it 20 mile plus at WOT most of the time. No issues. Engine ran great. So, what I learned. 1) If I ever look at a boat to buy again and it doesn't give the "All Good" beep, I will find out why. I'm not boat mechanic but I would think any outboard with auto mixing on the oil would have an alarm to let you know it is all good. If I had fixed the alarm first, I would have at least known it was an oil issue, not a fuel issue. 2) I don't have the mental fortitude to be a boat flipper or a boat dealer. I like my money too well. 3) Just because a guy hangs a shingle saying he is a boat mechanic, it doesn't make him a boat mechanic. I should have taken it to a proven boat mechanic like Fishinwrench. I was trying to help a guy out. Thanks for the input to try and help me.

I found one.

I accidently dunked my Motorguide Pinpoint GPS FOB for an XI5 in the live well. Screws weren't as tight as they should have been so it got wet inside and ruined it. These things are extremely hard to come by. Just by chance, does anyone have an extra they would sell?

I bought this boat in the spring to replace mine. It had a few issues that are now repaired. I've decided to sell both boats, thus one now and the other in the spring. This pretty much all new fuel supply from the tank to the engine including a new pressure regulator, high pressure fuel pump (OEM), and filter. The problem it had was the oil level in the engine mounted tank would get low and it would go into gaurdian mode. That is all taken care of now. It was never without oil, just low in the tank. I have it listed on facebook at this link. https://www.facebook.com/marketplace/item/889326526373172/?mibextid=dXMIcH

I did take it to a mechanic. I thought he hooked it up but I will check. He doesn't seem to know why it is doing this either.

Ok, I'm at my wits end, if I ever had any. I have a new fuel filter, new fuel pressure regulator and a new high pressure fuel pump. I have fixed the issue that it originally had but now it is doing something different. It will stall at 3,000 rpm like it is bogged down. Then it will eventually get up to 5,000 and get on plane. Takes a while to get there. Before all this it would pop right out of the water, get to 5,000 and plane quickly. Any ideas? I was getting ready to pull all the fuel lines and filter for replacement but I just can't seem to wrap my head around fuel lines being the problem. The primer bulb does not lose prime during this. It does lose prime after setting for a few hours. I just want to get this thing running so I can sell it but I want to have confidence the engine is fixed before I sell it. Also, the fuel pump and pressure regulator are OEM, not cheap Chinese. ,

While I was waiting to try and get into a dealer, I thought I would test coils. It has two new coils and the rest look original or at least OEM. I ohmed from the connector pins to the output. The new ones did not ohm at all on any pin, just gave me the OL. The older ones all tested at .9 on the center pin. Does this indicate the new ones are bad?

Thank you. I will head down this road and see where I end up. I will post back here to follow up.

OK. 😕 that doesn't sound good. Just to clarify, with the alternator, do I still have the stator? I can see the alternator but no stator.

Thanks for the info. I added a pic of the model and serial numbers.

Quick question, is the voltage regulator in the alternator? Probably a silly question but I can't find it.

Thanks for the reply. I was so focused on it being fuel at the time I never thought to check those things. I will put it on the water again and look at those things. I will check the plug in the ECM. It doesn't die, it will bog down like it is starving for fuel then start doing what it shows in the video, cutting in and out. As long as I keep it down around 3,000 it runs fine. It has enough power to push it back up on the trailer and it purrs like a kitten at idle even after it acts up. Thanks again for the help, I will post what I find out on those other things. It may be a next week sometime before I can get it on the water.

I purchased a 2007 Nitro with a 150 Mercury 150 EFI. Boat ran great for the test drive but when I put on the lake the next time after about 6 miles it gave me some problems. At WOT it will start bogging down them it starts cutting out\miss firing. Changes the fuel filter but kind if at a loss on what to look at next, fire or fuel. It has 120 compression on all cylinders. Looks like 3 coil packs are new and 3 are original. I shot a video of it yesterday but can't upload here so I uploaded to YouTube. This is the link Thanks in advance for any advice

What do you have? I'm thinking of upgrading.