Help, Yamaha 225

F

fordzilla

Member
Can someone tell me if this is normal? Watch carefully at idle, the fuel level goes up and down in the fuel filter, and sounds like a pump comes on and off. Injected engine I would have thought it had to have continuous pump pressure.

https://youtu.be/TG_l2tim7yo

The engine intermittently almost entirely shuts down when full out. However it also seems to conside with charge voltage at about 16V for some reason. So, is my problem fuel related or power?
 
Your probably hearing the low pressure pump turn on and off. That's normal. You can see fuel level go up and down when the pump turns on and off. A fuel pressure tester will help discover if it's fuel related.
 
i am thinking collapsing fuel line.. my honda did this and was very hard to diagnose. a section of fuel line with a sharp turn in it kept collapsing and starving the motor when ever it had to pull hard... try hooking up a portable directly to your fuel intake on the motor... frustrating problem to say the least..
 
I am chasing fuel for sure. I have the YDS Software however am unable to get it to connect to the outboard yet. Going to try another couple things and see. I have version 1.33, and everything I have read says that it is very specific about requiring windows XP or earlier. I found an old XP Laptop and tried there, but still not seeing computer of the outboard. I sure wish I could find V2.0 so that I could load it on my Windows 7 Laptop.
 
Update:

I changed out the entire Vapor Seperator bowl thingy with a new (used) High Pressure Pump. All seemed good (Although it seems to have lost a huge amount of bottom end power, takes forever to get up on plain and its only a 14x17p prop which hauled when I first put it on). Ran good, reliable for about 10miles or more flat out, then all of a sudden, dropped from 5500RPM to 1000. This time however, I was able to pull throttle back and then immediately to full power again and the engine would go back to flat out. After doing this a number of times, the "Falling Down" seemed to get closer and closer together (like every 10seconds or so). I am still thinking fuel, as the bottom end seems low on power, anyone know what the fuel pressure should be across the injector rails? I thought I would look at that. The other thing I noticed is when the lift pump is pumping to the bowl, it seems to draw the fuel below the filter media (even more than in the video above). Could this be part of the problem? Plugged pickup? Plugged fuel line?

Any help would be wonderful!
 
OMG

This exact same thing has been ongoing with my 140 Johnson for about 1 month, at shop 4/5 times and no reason/cure found. I ran a separate direct fuel line with tidy tank and it still happened, computor checks out, fuel pump, impeller, heat temps all checked out. Starts after 30+ mins running, then RPM reduces on own from 4200 to 3000 max. Shut down wait 30 + mins then comes back for another 30 min run. Sounds like Fordzilla and I have same issue? Ideas for us?

HM
 
Very similar. Computer checks fine, but only happens after around 30min for sure. Also going to try tidy tank, however doesn't explain bottom end loss of power. I am going to try to hunt down a fuel pressure Guage to attach to injector rail to test.
 
It almost sounds to me that your charging circuit is to high, 16v should be in the neighborhood of 13.9 to 14.2 the computer may be sensing something wrong and cutting down the rpm, putting it into limp mode, rectifier, stator, just a thought and my 2 beans
 
Don't know the F225 ....and am not great troubleshooting outboard issues but I do have a yami HPDI and the only thing similar that has happened to me as to what you are explaining was I had a small hole/tear in one of the 2 LP Fuel pumps. The LP pump diaphram/gaskets in the HPDI are supposed to be replaced as maintenance item after so many years. One LP pump was fine and the HP pump was fine but the 2nd LP pump had the little hole. I'd lose pwr then pull back on throttle ....then upon accelerating would be fine again until after 10 seconds same thing would happen. The size of hole I'd think would perhaps change the resulting symptoms a bit.
As far as what relates to what Big.riff mentions ..... I have had sudden rpm loss due to spark plug issue however that was immediate drops and increases of rpm that appear as surges of pwr and sudden drop.
 
Last edited by a moderator:
I was thinking more along the lines of a coil. Have seen it in powersaws where coil gets hot and quits. Let it cool and it works again.
 
I think I might have figured it out. It seems when I am flat out, it pulls the ball flat. So that tells me that there is restriction somewhere before the ball. Which in my case only leaves a short piece of hose and the tank.
Whenever it dies, if I were to go back and check the ball, I have to pump for a long time to get all the fuel back into the engine as well. So, next step. Going to run on a day tank and see if all goes nice and smooth.
 
That could also be the fuel tank vent. If it is plugged or partially plugged the fuel pump can't suck the fuel. If the vent is anywhere that saltwater spray gets to it ...it will eventually plug up.
 
Quick way to check is to use compressed air into fuel filler and see if you can hear it coming out vent. At least you know fuel vent hose isn't plugged further in towards the tank
 
Sorry I thought you had already tried a portable fuel tank as Trophy wife suggested and bi passed your boats regular fuel supply but sounds like you haven't ??? ...that would narrow things down to the motor itself if you still had the issue running the portable tank directly.
Further to what Profisher has suggested I have heard that antiphon valves on fuel tanks can fail/clog and that would also cause a starved fuel situation and primer to collapse.
 
Hook your engine to a day tank so that you can isolate the problem. Depending on the brand of boat you may have plugged pick up screen, if no screen then it could be a piece of silicon or rubber getting stuck in the anti siphon valve. I have had your problem with both types of tank set ups. The alternative fuel source will tell you where to look.
Good luck...
 
claymcpher said:
It almost sounds to me that your charging circuit is to high, 16v should be in the neighborhood of 13.9 to 14.2 the computer may be sensing something wrong and cutting down the rpm, putting it into limp mode, rectifier, stator, just a thought and my 2 beans
Click to expand...

I agree. 16 volts will likely put the ECU in a limp mode. Sounds like that's what's happening here. I'd disable the charging system and try it out but that problem still has to be fixed regardless. It will boil the battery.
 
Ok, so ran on small day tank, without a hiccup. Obviously $25 in fuel only lasts so long on a 225... But I believe my problem is either hose or pickup in tank, as the ball didn't pull down flat while on day tank either.
As for the charging, it only does it once and a while, so I'm gonna look into batteries and stuff, and see if I can't get to the bottom of that as well. There were no codes in the computer from high charge voltage either. Might be just a weird anomaly.
 
Ok, I "believe" I have fixed the problem. Replaced fuel lines from tank to outboard, including the priming ball. Went I out yesterday and not a hiccup!
I believe it was these blue fuel lines it had that have a plastic liner inside them. Will keep posted if problem reoccurs but fingers crossed I have it resolved.
Thanks everyone for the help!
 
You must log in or register to reply here.

Similar threads

Christl Waters
2009 Boulton 20 foot Sea Skiff
Replies
1
Views
1K
macro
M
M
WTB 1997 Yamaha 225 parts motor
Replies
7
Views
393
ship happens
ship happens
Fisherman Rob
Kicker stalled and wont start
Replies
17
Views
2K
lazylump
lazylump
C
Yamaha f225 fuel starvation after warming up
Replies
0
Views
531
Cabezon1
C
B
Yamaha F4 motor, quits randomly
Replies
5
Views
649
bpsuls
B
Back
Top