y pipe leaking?

[saintlee]

first time posting. allways reading posts. great advise allways.
i have a 2005 volvo 5.0 gl-e carbed, dps outdrive
After running the engine i found a small leak coming from area around transom
after looking with mirrors, looks like possibly the top of y pipe but i cant see the top bolts
seems to stop after after an hour of stoping engine.
any ideas
i was going to pull boat out of the water, remove exhaust pipes and bellow after the risers, then somehow plug exhaust on outdrive, fill y pipe with water and check.

 

[Justin Kennedy]

Re: y pipe leaking?

Good luck. I had the same issue. There is an oring where the y pipe bolts to the transom bracket. Be sure when you reinstall the y pipe that the bolts snug it up so that it doesnt leak. your probably going to have to pull the motor.

 

[tkrfxr]

Re: y pipe leaking?

There are a lot of sources for your water leak....try to pinpoint the culprit before pulling the boat.....

get your engine manual, and go through each possible thing that crosses the transom assembly....

I had a leak from a poorly sealed trim sensor cable....just one of a bunch of things that cross the transom assembly.

You have to be a detective and stake out the leak...until you find it...otherwise you are going at it blinbly.

 

[saintlee]

Re: y pipe leaking?

thanks for the replys
over the winter i changed to a dp-sm drive from a sx. when i did that, gimbel bearing, bellows, and trim sensor were all replaced.
besides that when i look with mirrors i can see trim sensor pass-thu real well, and its definitly well below the drive shaft, shaft also looks
dry. im on vacation in a week, will test then, hopefully will slide engine forward about 12 inches
will report back then
thanks again

 

[saintlee]

Re: y pipe leaking?

ok, back from vacation, I pulled the boat today and to my surprise i cant get the leak back while running off the flush hose.
run the engine for half an hour thinking heated water might be the trick.
Back to the drawing board
Boat will be back in tomorrow and will check for leak again
still think it is y pipe seal
any ideas are welcome

 

[Don S]

Re: y pipe leaking?

I pulled the boat today and to my surprise i cant get the leak back while running off the flush hose.

Put it in the water and try it.

 

[Justin Kennedy]

Re: y pipe leaking?

sounds just like mine, y pipe oring leak very hard to see. on my boat, the joint in question actually sits into the transom cut out. no way i would have seen it w/o pulling the y pipe. The owner before me must have had issues before because they actually tried to seal it with silicone. What the did, and did not realize was the used bolts on the bottom of the y pipe that were too long. this prevented the y pipe from completely sealing up because the bolts would bottom out before it snug up the y pipe joint. possible you have a similar problem considering you had this assembly apart not long ago?

 

[saintlee]

Re: y pipe leaking?

back in water and tests are complete
launched boat and sat tied to dock for an hour, no leak
started engine and within 6 min leak started
ran boat for 20 min, leaked whole time
brought boat to my dock (2 min run) and shut off engine
leak stoped after about 3 min
i can see drive shaft, shift cable, water inlet, 2 hydrolic trim hoses, trim sender wires and black plug next to wires
no leak on any of those
my conclusion is y pipe o-ring
but why only when engine running?
any one else?

 

[Don S]

Re: y pipe leaking?

Have you considered the possibility that the water is running down from someplace higher and just dripping off the bottom of the Y pipe? Maybe from the exhaust hoses at the top of the Y pipe?

 

[saintlee]

Re: y pipe leaking?

yes
both sides are dry
there is small amount of water inbetween the top 2 bolt to the ypipe
i went to locale dealer and looked at used transum assem to get more familar with set up
i tried to go by process of elimination
since i cant actually see the leak
i will keep checking other possibilitys

 

[Justin Kennedy]

Re: y pipe leaking?

Again, sounds just like mine. I checked every way possible, never could see the leak, but everytime I had the boat out, the end of the day, i loaded it on the trailer and pulled the plug, I had 10 gallons or so very warm water in the bilge. I finally decided to pull the motor and check the y pipe and sure enough thats what it was. The y-pipe was so corroded i can't believe the boat didnt sink. It might have been because my flappers were stuck down there as well probably keeping some of the water out who knows! If you need a new y pipe, there is a surplus store here in my town that just got one in new, old stock that Im sure he would sell for a good price. Let me know if you need it and I'll get his number for you.