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-   -   exhaust water leak help please (https://www.offshoreonly.com/forums/drives-lower-units/303316-exhaust-water-leak-help-please.html)

yoanalmirall 09-23-2013 01:20 PM

exhaust water leak help please
 
Hello i have a 26 foot formula with twin 4.3 mercruisers one of then is leaking water to the inside trough the exhaust Y pipe end side that seals with transom side i posted a video to be more exact , i need to know thats necessary to repair this problem is my first boat thanks here is the video of the Y flange leaking http://youtu.be/ZYMccnovm-E http://youtu.be/ZYMccnovm-E

Unlimited jd 09-23-2013 01:39 PM

Water will leak into the boat even when it's not running. And it will rot the transom if not addressed

phragle 09-23-2013 01:43 PM

easiest is to pull the motor to get to it unless you have access to an 18" tall mechanically inclined anorexic midget. Sorry to be the bearer of bad news...

yoanalmirall 09-23-2013 02:27 PM

Ok thanks buy my question is do you seal it from the inside or the out side or both sides ? Someone told me I have to.remove engine and drive is this true?

seafordguy 09-23-2013 02:52 PM

Yes - you need to yank the engine. The Y-Pipe bolts up from the inside and it would be impossible to get to with the engine installed.

That is a lot of water leaking too and the transom is exposed there from the inside so you need to fix this sooner rather than later. It sounds daunting the first time through, but it will be easy..... Lots of help to be had here on OSO so feel free to ask a bunch of questions.

dereknkathy 09-23-2013 06:20 PM

i take it this is on land with a hose to the drive? cuz this is a BIG leak. will leak worse when engine is shut off. do NOT put this in the water!! not even for a 10 min test drive. something goes wrong and it quits 100 yards from the ramp, you could be in real unpleasantness real quik.

yoanalmirall 09-23-2013 07:34 PM


Originally Posted by dereknkathy (Post 4000902)
i take it this is on land with a hose to the drive? cuz this is a BIG leak. will leak worse when engine is shut off. do NOT put this in the water!! not even for a 10 min test drive. something goes wrong and it quits 100 yards from the ramp, you could be in real unpleasantness real quik.

Yea the video was on land with the hose on I brought this boat 3 month ago and I found out about the leak just after lowered through the ramp it got full of water till the oil pan in less of 5 minutes I really want to fix this before the colombus day regatta here in Miami

dereknkathy 09-24-2013 05:29 AM

then pull tjhe motor right away...it is probably a bad y-pipe. a dropped bolt or socket into pipe will rot it out cuz of differential metal electrolysis. where are you? i have a y-pipe. but shipping is a bit of a hassle for something that big. a quik leak test is to pull motor and back boat down the ramp. then u can really see what's going on.

yoanalmirall 09-24-2013 06:36 PM

I remove the drive today and pulled the motor forward the y pipe is rusted and the bolts were to long and stuck thats why it wasn't sealing what am going to do is seal the exhaust from the outside with a rubber cap and also eliminate the Y pipe if I can then go with straight pipes thru the transom and problem solve what do you guys think?

seafordguy 09-24-2013 07:05 PM

Would probably work. You better have a LOT of confidence in that "cap"

yoanalmirall 09-24-2013 07:19 PM


Originally Posted by seafordguy (Post 4001570)
Would probably work. You better have a LOT of confidence in that "cap"

Yea I know and thanks! I will change it every 6 month to prevent a disaster anyway is inexpensive and fast to replace besides sooner or later I was going to go with the loud exhaust

seafordguy 09-24-2013 08:10 PM

I still think I'd fix it the proper way. If you've got the drive off and the engine unbolted just yank it and undo the 10 bolts holding on the transom assembly. Then out on an actual block off plate and go with your thruhull exhaust

the deep 09-24-2013 09:05 PM

This is all you need to fix it right . You may be able to get it on with just the engine pulled forward . http://www.mercruiserparts.com/showS...sp?pn=861776A2This is what you use when using through hull exhaust . Pull the y-pipe off and install this . I'm sure it comes with a new o-ring too . Part #11 here . http://www.mercruiserparts.com/Show_...EXHAUST+SYSTEM

dereknkathy 09-26-2013 10:55 PM

NO! NO! NO!!! there are 2 other exhaust vents on bottom of transom assy. if you wanna go thru-hull, you must remove engine and install block-off plate. i bought my Nova twice. first time was for that very reason. guy tried to seal exhaust from outside when block-offs were rotted through. didn't work. i dragged it home and replaced the engines that failed the float-test. he tried to caulk the 2 vents after putting a ferko (that is home depot plumbing stuff) pipe cap over hole exhaust tube goes on. if you MUST try it, your only chance is to get a big pipe tap for the 2 vents and thread pipe plugs in there. you don't need to remove transom assy to do it right. y-pipe or block-off bolts on from inside. 4 bolts. stainless 1/2 12 point head. or are they 3/8ths? don't break them...if you have a cherry picker and can't get motor all way out, pick it up and swipe a small pallett or a 2 or 3 2x4's and drop motor on them at floor level. ok, miami. anybody in s. florida have a merc y-pipe this dude can get cheap?


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