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First post, Honda 225 issue

Just in need of a few clarifications in trying to narrow down my fuel issue. I disconnected the fuel line between the high side and where it enters the rail. Turned on the key and it seems to be running to that point fine. Replaced the filter in the rail. Lightly blew air thru the rail and fuel seems to be flowing fine. I think it has to be a pressure regulation issue. First question, on the vacuum tank, once it is removed, should you be able to blow air in either of the two hose connection and have it flow? I tried both and no air flow thru either. Second, on the IAB switch, I tested it and it read 40 resistance so it should be fine but there is what looks like a plunger coming out of the bottom of this switch, should it be able to move freely if you put your finger on it and push up? Not sure hw to test the pressure regulator that sits on top of the port side rail but I replaced it las week so I dont think that is the problem. Just trying to trace out all vacuum lines to make sure that is not the problem. When I turned on the key for a few seconds before I started working on it the pressure read 70 today instead of the 90-95 it read last time. Go figure. Thanks
 
Just to clarify, it is the intake air bypass solenoid valve that I tested that has the plunger on the bottom. Also, the bottom hose coming out of this valve goes into the bottom inlet on the vacuum tank. This line has a one way white valve/ filter. Will it work without the filter or do I need to order one and replace it. When I blow thru the line it seems a little restricted.
Chawk I also checked the air vent filter behind the intake and changed it out just because it looked like it hadnt been changed in awhile but it seemed to be flowing good.
 
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That is a check valve and I have never had to replace one. The vacuum tank is just that, an empty tank and you should be able to blow in one side and have the air exit the other side.The IAB valve will not cause the issues you are having. Firstly, you need to get the fuel pressure down to 41-43psi at idle, when you remove the vacuum hose, with engine idling, the pressure should jump up to close to 48psi. It is imperative that is fixed first.Check your return line from the fuel pressure reg is not kinked or restricted,if you have replaced the regulator and the little filter that sits underneath it, then the only other thing causing your high pressure is the return line. Given what you said about the fuel pressure changes, it would seem this hose is the issue, check it all the way from the regulator back to the fuel pump, to do this you will need to remove the whole intake assembly. Your alarm I am guessing, is the O2 sensor telling you the mixture is too rich given the high pressure readings you mentioned, it is not faulty, just doing its job. Once you rectify these issues, if you still have a the original problem, you will need to monitor the pressure whilst the problem exists, if it's dropping, then we will need to look at the low pressure side.
 
Totally agree with Ian's recommendations.

The IAB solenoid will not cause your problems UNLESS there is a vacuum leak in the vacuum hose coming from the vacuum tank. The ECU activates the IAB Solenoid at approximately 3950 rpm. When activated, the vacuum is applied to the vacuum diaphragm on the intake (the one sitting just above the HP fuel filter) which in turn, activates the baffles in the intake, feeding more air into the intake manifold, which allows for a more efficient combustion.

If there is a vacuum leak anywhere in the system, your fuel regulator will not work properly. That is because the regulator relies on differences in vacuum to bleed off fuel pressure.
 
Thank you both for your replies. Good info. I traced out all the vacuum hoses, disconnected them, blew air thru them, checked for possible points where the hoses could be getting pinched. Blew air thru the hose with the check valve coming out of the vacuum tank. Check valve seems to be working when you try to blow air thru it back into the tank but when you blow the other way, air does
pass but some resistance possible due to the check valve itself. The vacuum tank, when I try and blow air thru either of the 2 ports is very restrictive to the point that you cannot feel air coming out of either other opening. Anyway I put the motor back together, with fuel gauge still attached, started engine, 41 lbs pressure. Not sure where the problem was but it seems to ne holding at 41. Will take it to the lake tomorrow and let you know how it goes. Again Chawk and Ian, thanks for your help.
 
Good luck on the sea trial. Let us know how it goes.

Wondering if one of the vacuum lines wasn't loose and all of your checking and re-connecting fixed that.

It's mysterious about the vacuum tank. I have no idea how it could get restricted. Did you make sure that the openings were not clogged?
 
No, I didnt want to do any thing with the tank until I received verification from you that it wouldnt hurt it if tried to clear it. Not knowing if there was possibly a check valve or something inside. Thanks again.
 
I am out on the lake now. Launched boat went about 2 miles, no issues. Trolled for about 30 minutes with kicker then shutoff kicker and started 225. Got to plane and it started to lung again and slowed to idle. I left The fuel pressure gauge on the high end pump so I could see what was happening if I had problems. Started the motor up and the pressure gauge was dancing between 20 and 30 lbs back and forth. pumped the bulb a few times and it came back to 41. The line going from the boat to the engne looks good. Any suggestions. Thanks
 
Are you saying that the engine slowed to approx. 1800 rpm's on its own? Or did you slow it down to idle? If so, there are only two things that cause the automatic slowdown - low oil pressure (green oil pressure light goes out on your console), or overheat (red overheat light comes on on your console.)

If you did the slow down to idle, and fuel pressure was dancing around, then I would immediately think air leak in the fuel line.

First thing to do is make sure that the drain screw that you open to drain the VST is closed tight.

Then, buy some clear plastic hose with same ID as your fuel line (I keep forgetting what that is). Use that between the LP fuel filter and the LP fuel pump. Run the engine until it starts to falter, and look for air bubbles in the fuel line. If so, just keep backing up, substituting the clear fuel hose until you find the source.

If no air bubbles observed, connect the clear plastic hose from the LP fuel pump to the VST. Test for air bubbles again. If air bubbles, check hoses and connections. If they are solid, then you will need to replace the LP fuel pump - about $160 on Boats.net.
 
Im actually parked in a cove while a storm goes over trying to find the source. Replaced the bulb and hose last time thinking that might be the issue. When I try to pump up the bulb either with the engine on or off it does not want to fill Unless my RPMs are up. Also when it starts to cut out is around 3500 rpms normally but today it was just planning out at about 5000 rpms when it started to cut out. No alarms or lights.
 
Lets keep to basics here. Your fluctuating fuel pressure is a result of your vapour separator fuel level dropping to a point where the HP pump is picking up what fuel is coming in at an inadequate rate.When you assist it with the primer the pressure will normalize until the level drops again.You need to isolate the low pressure side buy connecting a portable tank direct to the low pressure pump, if this fixes it then the problem lies between the tank and the LP pump, if not, then the LP pump is your likely issue.Try this and see how you go.
 
Just a few more questions before going to the lake tomorrow. First,when I turn the key on I hear the high pressure fuel pump start and the pressure goes to 45 lbs for about 3 seconds then the pump turns off and the pressure drops to 40 lbs. Then I start the engine and the pressure at i stays at 40. When I increase rpm to around 5000 it goes to 37-38 lbs until I decrease to idle then back to 40 lbs. My question, does that sound like it is operating normally?
Also, I put the engine in a tank and attached a clear fuel line from the tank to the low side pump and started it increasing rpm to around 5500. No issues or bubbles in line. Next attached to water seperator, bypassing fuel filter (low side) and did same test, no bubbles or issues. Next attached to fuel filter (low side) bypassing water seperator and performed same test and got some bubbles. Am going to bypass the oow end filter for the lake trial and see what happens. Didnt matter what I did I could not get it to stall like it has been in the lake,of course! Even putting everything back the way it was. So well see. Just curious about the pressures that I mentioned above and would like to make sure that all is well with them acting like they are. Chawk or Ian I appreciate your input and when we get this figured out I owe you both a pizza or steak.
 
Sounds like the HP fuel pump is acting nearly normal. Fuel pressure should stay in the 40+ range through all ranges, but the 37 - 38 should not cause you any operating problems.

The bubbles from the LP fuel filter to the to the LP fuel pump is a problem. First place I would check is the rubber seal around the LP fuel filter bowl. Then when you re-assemble, make sure the screws that hold the bowl to the frame are nice and tight. Before re-installing, rub Vaseline on the rubber seal.
 
Get someone that can do a long & short fuel trim diagnostics for you the diagnostics will put you in the right direction
 
Just a follow up on the issues that I was having last year with the 225. Sorry for the late post, I thought I had already posted on this but evidently had not. Thanks to Ian and Chawk's help on everything. I checked every hose and filter and pump on the engine and all where working good but still had the stalling issue. Finally had enough and pulled into a cove while I was on the lake and started looking into other issues. Removed the plastic covering off of the cables and fuel line between the engine and boat and started wiggling lines. Found that when I wiggled the Hot wire that it caused the engine to stall. Traced it to one spot on the cable and removed the insulation from the wire. Found the main power cable, due to the raising and lowering of the engine, to be broken. So evidently when the unit was just right, it would break connection and lose power to the engine causing it to stall. Fixed that issue. Boat ran good the rest of the day. Then, the next day after I had been trolling for about an hr with my 15 hp honda kicker motor, I started up the 225 and got to plan, and the boat died again. As was suggested earlier in the post, I went back and squeezed the bulb to the 225 3 or 4 times, problem solved. Hit plan and worked great the rest of the day. So, I found (2) issues really, #1 the broken wire, and #2, every time that I am done trolling, I have to squeeze the bulb to the 225 3 or 4 times and that eliminates the stalling issue. The fuel line runs to a onboard filter out of the tank and then the line T's to the 225 and the 15 kicker. Took the boat the Lake Powell last week, fired right up and in running it all week, not one problem. Again, thanks to all for your help. This forum has been invaluable to me!
 
Normally, once the fuel is constant in the fuel system you should not need to pump the primer bulb again. I suspect you may have an issue there the kicker T's off of the main line. Check that the lines at the T are sealed well. If so, consider adding a check valve at the T where it branches off to the kicker motor. That would keep any air from back-feeding to the main motor.
 
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