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New owner of a 2004 BF225

Update: launched her today for the first time. But let me back up a bit first. I changed the lower unit and engine oil and went to start it using a barrel. I had trouble getting it to start. Looking at the low pressure fuel bowl it seemed it was not filling all the way full. After slowly pumping the bulb I finally got her to fire. She ran kinda rough for a bit with some surging then settled in with a fairly smooth idle. Moving forward to today I launched her and she ran fine for about 20 mins. After that she would cut out or “miss” at loads over 4500 rpms. When I popped the hood the low pressure fuel bowl looked partially filled with fuel (in my mind it should be 100% full). When I returned home I pulled the plugs and some white was observed on them so that tells me it’s a lean or fuel starvation condition. Any thoughts where to look? All new filter are installed previous to running it.
 
The lower pressure filter bowl on my 225 runs at about 30-40% full - runs fine.

When your engine starts running rough try squeezing the bulb a few times, this will fill the LP bowl so you can see if it makes a difference.

Did my first tank test on 2018 today and also had initial hard starting but I had changed all the filters, replaced the the external water separator and drained the vst - I just pumped the bulb until it became hard and it started first time.
 
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I attempted to squeeze the bulb and it only made it worse. It seems that perhaps the check valve in the bulb is malfunctioning. Any recommendations for a replacement primer bulb? I figure it’s an easy thing to replace considering it has a difficult time building pressure.
 
One other clue perhaps is she also idles around 900-950 rpms. I have new throttle cables on the engine and I did confirm that they allow the throttle to return to the stop. The shift cable is very tight and difficult to get into neutral as well. I’m planning on ordering a new cable this week. Any recommendations?
 
I did some more digging and removed the IAB valve. It’s frozen solid and will not budge a mm. Any recommendations to free it up?
 
Are you talking about the IAB solenoid or the IAB diaphragm that sits in front of the HP fuel filter?

If the latter, pop the arm off the IAB shaft and see if it's the IAB itself, or the diaphragm that's frozen.

If the IAB itself, send me an e-mail at [email protected] and I will send instructions on how to fix it.

If it's the diaphragm itself you may have a problem in that it is not a separate part, but integral to the whole IAB - $343 on boats.net.
 
OK. Understand the IAB shaft will not move. As I posted - send me an e-mail at [email protected] and I will return instructions on removal and repair. If you are really lucky, after removal, you can get some penetrating oil down in the shaft and get it loosened up. If not, I describe a tricky disassembly that you might try.
 
chawk_man said:
OK. Understand the IAB shaft will not move. As I posted - send me an e-mail at [email protected] and I will return instructions on removal and repair. If you are really lucky, after removal, you can get some penetrating oil down in the shaft and get it loosened up. If not, I describe a tricky disassembly that you might try.
Click to expand...

Thanks for the emails chawk! I did get it loosened up but at the expense of some parts. I’m calling it a loss and have a used on the way from EBAY. I figured I’d roll the dice on a $150.
 
My “new” used IAB manifold cover assembly arrive today. The valves all work smoothly. Only issue with the “new” one is the vacuum actuator won’t hold pressure and slowly leaks down. I swapped my original actuator on the “new” assembly and everything seems to work as it should. Any tips now that I have a freely moving valve to help it reamain so?
 
I agree with that - test and lube at every 100 hour maintenance or end of every season, whichever comes first. You will need to get in there anyway in order to change out your HP filter, which should be changed out every 100 hours, too.

As for lube, I actually use a couple of drops of light machine oil (WD-40 or similar) in order to keep the spring and lower part of the shaft loose AND clean. It's pretty tough trying to get grease in there and I worry that grease would eventually clog up the works. Remember to test the diaphragm when you do that.
 
I installed the used IAB and swapped my diaphram on to the “new” one. I replaced all the fuel lines from the tank to the primer bulb. New primer bulb as well. I water tested it and it ran very well. In fact i was able to run it up to 6000 with no problem. My new problem emerged when i idled her down when warmed up. It idles no problem but idles high, in fact about 1000-1100 and shifting is difficult. I sprayed carb cleaner around the intake and i know think the intake gasket is leaking near the bottom. When i installed the used IAB i noticed that the bottom left intake bolt was missing so i ordered a replacement and installed it. I finally am running out of time and dropped her off at a local shop i trust to replace the intake gasket and take a look. Ill update as it progresses.
 
Just grease the bolts liberally with general purpose grease and remove the lower unit once a year to inspect and re grease bolts. It also pays to grease the support bush with a teflon based grease such as Mercury's 2-4C
 
With idle that high it will be hard to shift. Once you get the idle back down to 650, it should be much easier to shift.

I wrote this up for my own benefit a few years ago...

Throttle Control Adjustment

First, with engine off, take off the cover, gently put in gear (do not force it – if much resistance, get someone to turn the prop by hand while slipping it into gear), push throttle full open and inspect whether the throttle lever arm (at the cable cam wheel) is up against the stopper. It should be.

If not, before adjusting, pull throttle back to idle speed, put shifter in neutral, and follow the cables to the throttle cam wheel (on top of the engine toward the rear) and make sure they are not damaged or kinked.

At the throttle cam wheel, make sure the adjustment nuts are tight. Measure the distance between the adjustment bracket and the end of the cable adjustment threads. They should be 9 mm on both. If not, adjust.

Back to the throttle cam where the lever is located - measure the length from the end of the threaded part back to the adjustment nut - the open side (to your left as you are facing it) should be 14 mm. The close side (to your right) should be 19 mm. If not, adjust.

Put back in gear, and push throttle all the way forward. Throttle arm on the cable cam should be up against the stopper. If not, then you likely have a problem with the cable from your throttle control to your engine, which will need to be adjusted or replaced.

If the throttle arm is up against the stopper, then look at where the roller sits in the throttle cam. It looks like a fat inverted "L". The roller should be almost touching the top of the narrow part of the "L".

Then pull the throttle lever at your control all the way back, and put the engine in neutral. The roller should now line up with the "V" mark on the foot of the "L."

If not, adjust the linkages until the roller does what it is supposed to do – nearly touch the stopper at full throttle and line up with the "V" mark at minimum throttle.

For more detail, see pages 3-18 to 3-21 in the Helm Shop Manual.
 
So far so good. It appears my issues are currently resolved. The high idle was caused by an inproperly installed intake gasket. The previous owner (I assume) had the injectors rebuilt and incorrectly installed the intake gasket. Now she’s purring like a kitten. Now I just need to put some hours on it.
 
So far so good. It appears my issues are currently resolved. The high idle was caused by an inproperly installed intake gasket. The previous owner (I assume) had the injectors rebuilt and incorrectly installed the intake gasket. Now she’s purring like a kitten. Now I just need to put some hours on it.
 
Thanks Chawk . I will update when I get some hours on her. I sure appreciate everyone’s help. I suspect with a 14 y/o motor I’ll be back with more questions.
 
Update: I had a chance to put a few more hours on her and she’s running well. The current prop is a good fit as well (6100 rpms max). Since my ownership the trim guage has not worked. I tested the sensor and that checks out. I fiddled around with the connections on the guage itself and have determined the problem is internal so I’m in need of a replacement. If anyone has one hanging around taking up space in their garage please PM me.
 
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Did you check the readings at the gauge (i.e. right at the end of the signal wires). I replaced my sensor, which the arm had broken off, but still didn't have a signal at the gauge. Tracing back I discovered that the connector plug under the cowling was damaged also so I had to remove it and hard wire the sensor in place.
 
Yes I did. I cleaned all the stud terminals as well but noticed when any pressure was applied to the signal stud (pushed in or lightly pulled out) I would get erratic action on the guage itself.
 
You might want to check the bullet connectors going to that meter. According to the electrical wiring diagram in the back of my Helm shop manual, there are five of them. Assuming my eyes and magnifying glass are not playing tricks on me...

Black & red/white are the meter power connectors.

The sensor connectors are:
Black/yellow
Yellow/blue
Black
 
Starting to put a few hours on her lately.last night I finally had the opportunity to go fishing. She ran perfect on the way out and idled down well for trolling. We fished (trolled) for about 3 hours at about 700-900 rpms. We pulled lined and headed back In, once on plane I noticed a slight miss at rpms from 4200-5500. I’m assuming that the 3 hours at idle may have loaded her up a bit. Is this normal to expect this.
 
Are you talking a miss, or a change of about 100 to 150 rpm's. If rpm change, then it has happened to my engine, too. I think it's the intake air bypass (IAB) solenoid kicking in and out, or it's stuck. Some other folks have told me that it is the VTEC system kicking in and out.

In front of your HP fuel filter on the back of the engine, there is a vacuum diaphragm that controls the IAB arm. Loosen the right side of the upper cowling and peel it back. Take needle nosed pliers and grab the arm coming out of the diaphragm and pull it back as if the diaphragm is being activated. Then let it go. It should snap back into place. If not, then you will need to remove the IAB and get penetrating oil on the shaft to loosen it up.

If the IAB arm does snap back into place, then remove the vacuum line to the diaphragm. Use the needle nosed pliers again to push the arm back into the diaphragm and place your finger over the vacuum line opening. When you let go of the arm, it should move out a little bit and stop and stay there until you remove your finger. If not, then the vacuum diaphragm has failed. Unfortunately, it is not a separate part and is integral to the entire $340+ IAB assembly.

If you want more detail on removing and servicing the IAB, send an e-mail to me at [email protected].
 
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