yamaha 225 - hole, water leak in engine block
#1
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I was fishing today - engine was running fine, no loss of power etc, ran about 5 miles out, engine was peeing fine, no alarms....I decided to take the engine cover off as I remembered while flushing it recently with fresh water I saw water coming out of the drain area beneath the cover...I pull the cover off and there is a stream of water squirting up thru a hole in the top of the engine. hole, about 1/16th of an inch, and could stop the spray by putting my finger over it, so not a ton of pressure....but in 25 years of boating I never had that happen...looks like corrosion caused the hole...I've always flushed after each use so??? It's on the top of the port engine below where the thermostat is, I guess the part would be the crankcase assembly...(part: 65L-15100-00-94 CRANKCASE ASSEMBLY )
what are my options...can the hole be tapped and plugged with a screw...marine epoxy/putty...or do I have to replace the whole block?
I took a picture for clarity, but can't see how/where to attach the image.
what are my options...can the hole be tapped and plugged with a screw...marine epoxy/putty...or do I have to replace the whole block?
I took a picture for clarity, but can't see how/where to attach the image.
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sorry - when I wrote below the stat, I did not mean the gasket that is part of the thermostat assembly...I meant if you are looking down at the stat, the hole would be down below, about 2" down and back about 1"....on the crankcase block itself...its actually a hole in the metal housing...for the life of me I can not see how to post a pic...I read the faq, and I do not see where you can check attach an image.
its a 1999 yamaha 225 ox66, fuel injection, 2 stroke
its a 1999 yamaha 225 ox66, fuel injection, 2 stroke
#4
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petep, go to a free photo-hosting site, like photobucket.com or fishpix.com, and upload your photo there. Then, copy the img info below the pic you want to put on here, and paste it in you reply. It will show the photo.
#6
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ok - here's a pic...
see just below the 2 blue wires/black wire...there is a small hole at 6 o'clock
http://s381.photobucket.com/albums/o...=yamaha007.jpg
see just below the 2 blue wires/black wire...there is a small hole at 6 o'clock
http://s381.photobucket.com/albums/o...=yamaha007.jpg
#9
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I think I will try some jb marine weld....
I'm going to check, but you can see that one corroded bolt up above...perhaps that provides a ground or electrical path, and there is no path now...so maybe just salt + electrolysis ate away at the metal....not nearly enough pressure to cause a weak spot in aluminum to fail....maybe a meter will tell me something...
I'm going to check, but you can see that one corroded bolt up above...perhaps that provides a ground or electrical path, and there is no path now...so maybe just salt + electrolysis ate away at the metal....not nearly enough pressure to cause a weak spot in aluminum to fail....maybe a meter will tell me something...
#10
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Looks like it's been leaking a while and that's why the bolt above it is rusted. Have you owned that motor since new?
#12
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An epoxy product, like JB Weld will work for a while, but the corrosion from where the water touches the joint between the aluminum and the epoxy will eventually spread and lift the patch. Welding it may be the best long term fix, but the problem is that there is usually a lot more corrosion inside the hole and the weld area may get to be pretty good size before the welder finds clean enough metal to get a good weld. The corrosion may have started at a void in the block casting. Hopefully all of the walls are not about to fail.
#13
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Had that happen to an early 80's black max, but not as old as yours, it was only 3 years old when it happened, merc replaced both heads for us.....bad casting or something....try a good welder....maybe you can get a couple more years out of her.
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I think there are other people that have had similar problems with big Yam's. A while ago there were multiple threads on this subject. I know there were some on Stripersonline discussing this matter. What year is your motor?
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similar problem. the leak caused starter to rust/fail. I notice when flushing water coming out of top as did you and tracked it down to the part of block near temp sensor. pics shown. I'm going to try JB Weld after cleaning and scraping area around hole plus maybe some fiberglass or fabric to hold it a little better. It would be nice to put something also to hold it down on the spot (besides the JB weld holding it) just to keep it from tendency to lift off. Any suggestions? 2006 F250TXR
#17

How about carefully drilling and tapping a few screw holes into the casting and then bolt the preshaped aluminium patch down over some JB Weld etc. Put Duralac or some similar isolator product on the bolts if using stainless or if you want to do it better thread up some marine grade aluminium bolts instead.
#18
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One of our 2006 Yamaha 225 with 900 hrs just developed the same hole. I was wondering if anyone's "patch" repair has held after some use. We have used JB Weld as shown by a video online...... but it isn't holding so far. Thanks.
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#20
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I have done this repair. Pm will be sent.