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Honda BF225 Corrosion

T

Tom L

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Pruchased my BF225 in 2009. In 2015 had to replace the lower unit due to corrosion. I was out of warranty by one year. Honda sold me a new lower unit for half the price ($1600). Now in 2017 there is a hole in the block and heads. Water shooting out under the cowling all over the place. Honda said sorry but we can't help you. I got a repair estimate of $8000 to replace the block and heads. I'm really disappointed I only got 8 years out of this motor. Will never purchase another Honda product again.
 
This is something I've never heard of. Sorry you feel that way - how many hours did you put on the engine?
I have a 2007 225 with about 970 hours on it and no corrosion issues. Maybe something specific to where you boat?
 
Outboards are quickly joining the " it can not be repaired , buy a new one " line of products.---- That was started by VCR / television / radio / electronic products years ago.
 
Agree with Metal-Chicken on this. My 2007 BF 225 has 2000 hours. All in saltwater. Flush after every use. Keep on a lift in front of the house. No discernible corrosion. Well, there are some rust spots on some of the bolts, but I treat that whenever I pull maintenance.

Aristikat put over 3000 hours on his BF 225's - all saltwater. The Coast Guard regularly gets 5000 hours or more out of them.

How often do you change your zincs? How often to you clean the mating surfaces to make sure they have good contact? Do you make sure that the mating cable from the engine bracket zinc has good connection to the engine? Zinc's should be checked & cleaned at every 100 hour maintenance. When they lose 30% to 40% of their weight, they should be changed.

One other issue. If you park your boat in a marina for any length of time, make sure your motor is lifted out of the water and kept there. Stray currents for shore power to adjacent boats will accelerate galvanic corrosion.
 
My 02 popped a hole thru the block at the T-stat at 600 hrs, right after I replaced the Mid-Shaft bearing! I have a thread on it on here somewhere. Not sure where your hole is but I have been using Steel Stick with great results . I have about 900 hours on mine now . Just have to keep an eye on it.
 
Is the hole in the water jacket at the bottom of the block, port side? If so, I had the same thing happen to my 200. Do you happen to boat in shallow water? I think on my block, it just cannot flush out sand and sediment adequately. That is what causes the block rot. All of the manufacturers have this happen. It is not exclusive to Honda.

I ended up buying a factory new short block and doing the swap myself. I could probably do it in 4 days now that I have done it. It took my a total of 12 working days spread over six months to do it the first time. Anyway, it is a straightforward project,hella lot cheaper than a repower or paying someone else. Factory new short block is $2400. Probably another $400 in other parts. Just need an engine hoist and some hand tools.
 
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My creek isn't the deepest, but I am not churning up mud every trip. My prior boat had a 130 Evinrude that held up much better than this Honda. Again, it runs great, but the other issues with it make me think a new Honda is not in my future . paint sucks, corrosion, and lack of dealer support in my area, to name a few
 
A deep dealer network is really the only problem with the Honda outboards. But, I have found mechanically they are simple to work on. The fuel system is the real bugaboo, and these engines are sensitive to proper fuel flow. I think the fuel injection system is the single largest section of the service manual. Honestly, most of the issues stem to lack of use in my opinion. The day you buy a boat, everything is broken, you just don't know it yet.
 
For any motor, higher hours are better when discussing corrosion. Motors / engines are built to start and run, continuously. Since the motors have 2,000-3,000 hours on them I assume your are using them quite often compared to 900 hours. Corrosion starts the minute you shut the motor off and continues until it is started again. Standing idle for long periods of time is not ideal. I flush mine too after each use, but I feel it doesn't do all that much. Many of my friends in Maine never flush and leave their boat on mooring all summer. Typically the lower the hours, the higher corrosion.

Mine are 2006 and replaced 1 powerhead last year. They have about 900 hours.
 
My 2003 BF225 with 700 hours is in bad shape and I could use some advice. The engine oil is a murky beige. Cylinder #6 failed a leak down test and after an endoscope inspection of the cylinder, I can see drops of the nasty water/oil sludge on the piston. Is it just the block that is likely leaking or is it the head as well?

Given a complete re-power with a different brand is pushing my comfort zone, I would like to get some opinions on the pros/cons of replacing the short block ($2449 at boats.net). Who's done it before and a) was it easier than it looks and b) did it substantially increase the life of your engine or are finding that you should have re-powered from the beginning because other parts are also failing?
 
16 years in saltwater? I would be inclined to let it go and buy new, if you rebuild it is going to be costly if you do it properly, even if you are doing it yourself.
 
Until you disassemble and determine what really needs to be done you are just shooting in the dark. My short block replacement was cost effective. If you have a cylinder head issue the math may change. A factory service manual is a good investment if you are going to tear down and diagnose. The work is fairly straightforward.
 
Agree with Ian. I suspect that the exhaust tubes were never upgraded IAW Honda Service Bulletin #56, which contributed to the problematic leak-down and corrosion in #6.

A 16 year old engine with only 900 hours will continue to have issues with all of the bolt-on items to the short block, so if I were in your shoes, I would do the re-power. As discussed from the beginning of this thread, all outboards have some issues. The big 4-strokes must especially be rigorously maintained. My 225 is an 07 with 2200 hours and still runs great, but I'm a stickler on maintenance and the boat hardly ever sits for more than six weeks without being run. Nine months of the year it's typically run at least once every week.

I am still convinced that the Honda 200/225/250's are the best big outboards on the market. From what I hear, the Yamaha's are a close second, but they too have issues.
 
Are you sure it is a hole in the block. I know this is a dumb question, but it's rare if it does have a hole. The reason I am asking is because there are a couple of hoses that could have deteriorated or become loose and caused this issue. One goes into the vst and another one goes vertical into the midsection near one of the heads, Im not sure which side exactly. Oh an another hose goes under the starter into the block. Keep us posted.
 
Thanks for the recommendations. I'm inclined to take the head off and determine where the water is getting in and which parts are bad. The clean picture is representative of cylinders 1-5, whereas the one with the drops on it is cylinder 6. The leak down test results are as follows, from cylinders 1 to 6 respectively: 22%, 18%, 25%, 28%, 20%, 38%.

View attachment 197881 - 5

View attachment 19789 6
 
And here's a shot of the starboard side indicating the corrosion is not too bad on the exterior. Of course, beauty may only be skin deep. That said, I really do like this Honda and hate to part with it without giving it an honest try. Are there any tips for an easy disassembly, and what else should I look for?
Starboard_small.jpg
 
Confirm you said there's a hole in the block behind the fuel pump? Assuming that is so , then chances are your heads will be corroding internally and no way of telling how much. I therefore see no sense at buying a short motor as well as heads and all the other things that are going to need replacing, but you have nothing to lose by pulling the heads off and having a look.
 
How does the head gasket look? The heads are very easy to access and take off, but Chawk is correct, you will need the Helm shop manual for proper reassembly and torque procedures. Keep us posted.
 
Port_Exhaust Manifold_1.jpg
The exhaust manifold is about what I expected, the anodes have probably been useless for quite some time.

Port_Exhaust port #6 looking into head_1.jpg
Looking into exhaust port #6 on the bottom, you can see the salt buildup. I'm wondering if this is a recent blowout or has it been bad for some time.
 
You stated early in your post that water was coming out everywhere, can you be more specific? If water is drawn through the air intake it ends up at the bottom of the plenum (No6) where it will be most evident, hence the ingress you're seeing.
 
iang, I think you are on to the problem with the minimum of clues and it's something that I would never have thought of. When I removed the Intake Manifold Upper Cover, about a 1/2 quart of water poured out. You can see the residue along the bottom. So I'm a crossroads: to continue taking all the dressing off the head assembly and pop it off to take a look inside OR make the logical assumption that the water ingress is somewhere along the intake manifold gasket and not from an internal block or head corrosion leak. I'd be an easy decision to press on if there weren't so many disassembly steps. Any thoughts on where the water is getting in and whether I should continue the disassembly? I hate to fix something that's not broke.


Water inside Intake Manifold.jpg Intake Manifold, close up w water.jpg View without manifold or valve cover.jpg
 
So if there's water at the input manifold, how does it get to the oil? Wouldn't it get turned to steam and sent out the exhaust port? I'm not saying this is good, just not sure how it's making my oil murky. To be honest, I'm hesitant to get my hopes up thinking this is the problem and the block is actually ok. Could it be that some of the 'leak' is making its way into the manifold, vice coming into the manifold via a bad gasket?
 
I would reassemble and run the engine on a hose with muffs and good water pressure wjth the covers off and look for an external leak because it must have been pulled through the intake. The head will ultimately have to be removed to sort out the rusty valves
 
I just finished a compression test, #6 topped out at about 40 psi, the others were much higher and close to one another. I'll pull the head off Fri am. BTW, can I replace all these rusty and corroded bolts with stainless hardware, or should I be concerned about dissimilar metals making the problem worse? And can I get the Honda head gasket at an auto parts store or did Honda make a custom block for the outboards. I once heard it was similar to a Honda Civic engine.
 
You are getting ahead here, you started this thread by saying you had "water coming out everywhere".I have suggested you run the engine again and as ascertain where the water is coming from.There is no point doing all this work if there is a hole in the block. Only use genuine gaskets, they are not the same as auto.
 
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