Water blowing up from bilge?
- thunder550
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Water blowing up from bilge?
First time out after I got my boat back from the swim deck install, I noticed that there was a lot more water than normal in the bilge. Our roughly 5 hour trip on Friday yielded probably 2-3 gallons of water that came out when I pulled the drain plug, and that was after the float switch on the bilge pump had kicked it on at some point earlier too. Still need to track down the source of the leak, planning to empty the engine compartment out this coming weekend and dip the boat to see if I can find where it's coming in.
When I was doing my prop testing last weekend, I would start to get water dripping down from behind the instrument panel onto my feet any time I got up over about 40mph. The covers that I keep in the compartment right in front of the driver's position were slightly wet from spray too. I dug around a bit and for the life of me I can't figure out where it's coming from. Only two changes from previous times out (with no water dripping) are the drive shower and swim deck. Only thing I can come up with is over a certain speed, there's enough airflow through the bilge to pick up some of the water and spray it around, but it just seems unlikely to me that there's enough air speed to pick it up from the bilge, draw it all the way up the inside edge of the hull and deposit it behind the instrument panel.
I checked the head compartment in the same position on the other side of the boat and it's dry. Same thing happened both Wednesday last week when I was riding solo and Friday when I had a couple more people in with me.
Anyone have any ideas on things to check? The fuel tank vent on my boat is right in the area where water is dripping, but it's definitely not fuel that's spraying around...first thing I checked. No smell at all.
When I was doing my prop testing last weekend, I would start to get water dripping down from behind the instrument panel onto my feet any time I got up over about 40mph. The covers that I keep in the compartment right in front of the driver's position were slightly wet from spray too. I dug around a bit and for the life of me I can't figure out where it's coming from. Only two changes from previous times out (with no water dripping) are the drive shower and swim deck. Only thing I can come up with is over a certain speed, there's enough airflow through the bilge to pick up some of the water and spray it around, but it just seems unlikely to me that there's enough air speed to pick it up from the bilge, draw it all the way up the inside edge of the hull and deposit it behind the instrument panel.
I checked the head compartment in the same position on the other side of the boat and it's dry. Same thing happened both Wednesday last week when I was riding solo and Friday when I had a couple more people in with me.
Anyone have any ideas on things to check? The fuel tank vent on my boat is right in the area where water is dripping, but it's definitely not fuel that's spraying around...first thing I checked. No smell at all.
1995 Cobalt 252 - 502 Mag EFI - Bravo 1 - 21" Revolution 4
Re: Water blowing up from bilge?
Yup. It's the speedometer hose. There's a little water hose that attaches to a finger thingy sticking off the bottom of your transom. The speedometer is operated by water pressure coming up through that hose. Due to the age of your boat the end of the hose has probably gotten a crack in it. You probably have enough slack in it to just pull it off and trim it back a tad.
But there's no way that's going to put two to three gallons of water in your bilge. Are you using an on-board cooler? The ice will drain into your bilge. Driller reminded me of that this summer when I had unexplained water coming out of the drain hole.
Your Bellows could have a small crack in it as well.
But there's no way that's going to put two to three gallons of water in your bilge. Are you using an on-board cooler? The ice will drain into your bilge. Driller reminded me of that this summer when I had unexplained water coming out of the drain hole.
Your Bellows could have a small crack in it as well.
2001 262 502 GXI (because it sounds better than an 8.2)
From the Land of the Red Man
"Black Boats Matter"
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From the Land of the Red Man
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- thunder550
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Re: Water blowing up from bilge?
Ooh good call guys...does that speedo hose go all the way up to the gauge?
I though the water was from the inboard coolers (used them the two previous times out), but we didn't use them on Friday, so that rules that one out. Will check bellows. The swim deck shop drilled 4 new holes below the waterline for the braces, and moved 2 of the mounting clips for my water temp sender wiring, so now have 2 unused holes (that they hopefully sealed) and 2 new holes for that as well. Plenty to check on I guess. Hoping it's one of those and not the bellows.
I though the water was from the inboard coolers (used them the two previous times out), but we didn't use them on Friday, so that rules that one out. Will check bellows. The swim deck shop drilled 4 new holes below the waterline for the braces, and moved 2 of the mounting clips for my water temp sender wiring, so now have 2 unused holes (that they hopefully sealed) and 2 new holes for that as well. Plenty to check on I guess. Hoping it's one of those and not the bellows.
1995 Cobalt 252 - 502 Mag EFI - Bravo 1 - 21" Revolution 4
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Re: Water blowing up from bilge?
Yes the dish hose hours to the guage. Pull it off trim it and put it back on. Just like yt said.
Sounds like your new platform may have sprung a leak. What 3m sealer did they use. Yes cross your fingers it's not the bellows but it could be. There's one other small fitting that leaks and Aslan replaced his. But sure if that's only on a b3 though. His dealership twisted the hose going to it.
Sounds like your new platform may have sprung a leak. What 3m sealer did they use. Yes cross your fingers it's not the bellows but it could be. There's one other small fitting that leaks and Aslan replaced his. But sure if that's only on a b3 though. His dealership twisted the hose going to it.
03Cobalt220 8.1gxi DP
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Neenah Wi
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"Kids in Tow2"
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Re: Water blowing up from bilge?
So you drilled some holes in your transom for that fancy swim platform and now shes weeping...?? Looks good and it was well worth it !
Get some one to help you as the through bolts for the transom brackets are most likely the culprit. (since this just happened after the install)
But as everyone stated re tighten everything..... even the strap hook on the corners as they are stud bolted and loosen. The slightest seep once under water a foot or two can leak. Some small screws I find aren't blind drilled and go all the way through the transom even though the screws only a 1/2 inch long.
Drain plugs and Brass housings get loose as we crank the drain plug on and off and the 3 screws loosen a lot.. ( I use Teflon tape on my drain plugs)
But isn't that why we have Bilge pumps?? .. Bet your bilge is nice and clean right?? HAHA
Get some one to help you as the through bolts for the transom brackets are most likely the culprit. (since this just happened after the install)
But as everyone stated re tighten everything..... even the strap hook on the corners as they are stud bolted and loosen. The slightest seep once under water a foot or two can leak. Some small screws I find aren't blind drilled and go all the way through the transom even though the screws only a 1/2 inch long.
Drain plugs and Brass housings get loose as we crank the drain plug on and off and the 3 screws loosen a lot.. ( I use Teflon tape on my drain plugs)
But isn't that why we have Bilge pumps?? .. Bet your bilge is nice and clean right?? HAHA
2008 272 , 496 HO fo SHO
California Delta
Table Rock Lake
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- thunder550
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Re: Water blowing up from bilge?
Thanks guys, will attack the speedo tube Saturday then. Didn't even think about that as a possibility.
Swim deck guys used 3M 4200 I believe. I have some white streaks where it looks like it got wet and ran down a bit, how long does 4200 take to cure? Had the platform installed on a Thursday and took the boat out Sunday, so it had a good 72 hours to cure. Maybe not enough? I used 5200 when I replaced the temp probe, no runs off that.
Swim deck guys used 3M 4200 I believe. I have some white streaks where it looks like it got wet and ran down a bit, how long does 4200 take to cure? Had the platform installed on a Thursday and took the boat out Sunday, so it had a good 72 hours to cure. Maybe not enough? I used 5200 when I replaced the temp probe, no runs off that.
1995 Cobalt 252 - 502 Mag EFI - Bravo 1 - 21" Revolution 4
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Re: Water blowing up from bilge?
That sounds have dried by then. I'm sure they have installed a thousand of there own platforms but they could have missed something.
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
- thunder550
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Re: Water blowing up from bilge?
With the amount of water that's coming in I'm hoping it's easy to find and fix. Fingers crossed!
1995 Cobalt 252 - 502 Mag EFI - Bravo 1 - 21" Revolution 4
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Re: Water blowing up from bilge?
Just put a piece of paper towel down to see the drops.lol
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
- thunder550
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Re: Water blowing up from bilge?
Greasy as hell down there! Probably cleaned half of it out with my elbows and knees so farcmattj wrote: Mon Nov 27, 2017 7:17 pm But isn't that why we have Bilge pumps?? .. Bet your bilge is nice and clean right?? HAHA
Think some UV dye in the lake would work?Big Block Power wrote: Mon Nov 27, 2017 8:20 pm Just put a piece of paper towel down to see the drops.lol
1995 Cobalt 252 - 502 Mag EFI - Bravo 1 - 21" Revolution 4
- Big Block Power
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Re: Water blowing up from bilge?
Oh your lake doesn't glow? I thought that was normalthunder550 wrote: Mon Nov 27, 2017 8:35 pmGreasy as hell down there! Probably cleaned half of it out with my elbows and knees so farcmattj wrote: Mon Nov 27, 2017 7:17 pm But isn't that why we have Bilge pumps?? .. Bet your bilge is nice and clean right?? HAHA
Think some UV dye in the lake would work?Big Block Power wrote: Mon Nov 27, 2017 8:20 pm Just put a piece of paper towel down to see the drops.lol![]()
Greasy bilge. Can't have. Buy some of this it's great.
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03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
- thunder550
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Re: Water blowing up from bilge?
Do they sell it in 55 gal drums? 
1995 Cobalt 252 - 502 Mag EFI - Bravo 1 - 21" Revolution 4
- Big Block Power
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Re: Water blowing up from bilge?
The paper companies give them away. Our fish glow in the dark too
03Cobalt220 8.1gxi DP
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
"Kids in Tow2"
"Pot The Jus" Originator :-)
Neenah Wi
#ItsBu'sfault
#FARCON Marine CC Core!
- thunder550
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Re: Water blowing up from bilge?
Dang, you guys are good
much appreciated!
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