water leak only while moving

shane772

Cadet
Joined
Jun 3, 2017
Messages
13
We got a 1992 Bayliner classic given to us that wasn't operational. Found out the sterndrive was completely run dry. New sterndrive installed, bellows looked good, new gasket, etc. Any tips where I should start looking for the leak? It takes on a substantial amount of water while moving down the lake. Doesn't seem to leak while sitting. I'm confused, LOL
 

rallyart

Lieutenant Junior Grade
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Jun 7, 2008
Messages
1,175
Engine cooling system. You pump water from the lake in and if there is a leak in the system from a hose, gasket, or fitting, you will get water in the boat.
 

bruceb58

Supreme Mariner
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Mar 5, 2006
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30,454
Or rotten transom that causes a leak when the drive flexes the transom under load.
 

Grub54891

Vice Admiral
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Jun 17, 2012
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5,908
If the block and manifold drain plugs are open or out, It will take a lot of water in short time. Check there first, they are on each side of the block, and the manifolds are on the bottom of them. After that, look at hoses and clamps. If it still leaks look for cracks in the block, and manifolds, check your oil levels, If the oil is milky, you have a cracked block.
 

Alumarine

Captain
Joined
Feb 22, 2005
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3,684
It could also be leaking because of a gap in the rub rail on the outside of the boat probably near the rear of the boat..
There is a seam there.

Also does the speedometer work?
If not the speedo tube that runs from the transom could be leaking.
 

H20Rat

Vice Admiral
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Mar 8, 2009
Messages
5,199
Does it leak while sitting but the engine is running? Need more info... Given that it is a '92 bayliner, I wouldn't rule out a rotten transom like bruce mentioned above.
 

shane772

Cadet
Joined
Jun 3, 2017
Messages
13
First, thanks for all the repies!
A little more info:
- Boat hasn't been stored in the water, not sure if that contributes to rotten transom or not. Father in law bought it new and it was always covered/garaged. If transom is rotten, is there a way to check?
- Oil is full and clean, no water/milky look.
- With engine cover off and engine running, can't see any water leaking.
- Can't find any water leaking while just sitting, either running or not. I haven't had anyone with me to check while on the move.
- Speedometer doesn't work and the tube isn't hooked up. The new drive has a different connection than the original. Maybe I should try to cover this?
 

Horigan

Chief Petty Officer
Joined
Jun 12, 2016
Messages
614
You need to plug the speedo tube if it's not hooked up. When under way it measures dynamic presssure and will flow water into the boat if the tube is not connected to anything.
 

bruceb58

Supreme Mariner
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Mar 5, 2006
Messages
30,454
While it's in the water(not running) have someone stand on the drive and kind jump up or do some squats on it and see if water flows in.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
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Jul 23, 2011
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47,297
Late 80s and eatly 90s bayliners had marginal workmanship that lead to stringer and transom rot.

With boat on trailer, put yout finger on the joint where the transom shield meets the transom and have a 250# friend bounce up and down on the outdrive. If you feel any flex, it is most likely the transom.

Or test it in the water like Bruce mentioned

If you forgot to connect a hose, it will show up while running on the muffs
 

shane772

Cadet
Joined
Jun 3, 2017
Messages
13
Tried it on the trailer and it feels really solid. I'm 220lbs and I was trying to make it flex. Next test will be in the water, whenever I can take it out . . .
 

wahlejim

Master Chief Petty Officer
Joined
Jul 23, 2015
Messages
884
It's probably the speedometer tube as mentioned previously. Make sure that is plugged up.
 
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