Help-merc 18 water everywhere

[sylvan14]

New to this site. It seems to have a wealth of information.

I have an 82 18hp merc. I just replaced the the impeller and water pump gaskets. Now I have water filling the drive shaft cavity along with cooling the engine? The water does not flow into the drive shaft cavity until the motor starts running.
There is a gasket under the water pump, should I have used gasket sealer there? I did not use any when installing the new gaskets.
I have no idea what to do next other than drop a bunch of money at dealer.
Any help would be great.

Thanks
Dave

 

[green4themoney]

Re: Help-merc 18 water everywhere

kk dont waste money at the dealers just yet, so its filling up the driveshaft cavity? how can you tell this? you do know that most of the water after pumped through the block falls down this cavity and exits the exaust no? the telltale just lets you know the engine is pumping water, thats not where all the water exits from my friend, are you running the the engine on muffs, and is water exiting the telltale and not overheating? a few more details plz

 

[sylvan14]

Re: Help-merc 18 water everywhere

Water is coming out of the telltale, and the exhaust like it should.
But it also comes out of the 3 drain holes at the top of the lower unitthat drain the drive shaft cavity. Water is also coming out from around the top of the rubber boot on the shift shaft where it exits the lower unit and enters the swivel bracket.
I have run it with muffs and in a container and received the same results.
Thanks
Dave

 

[westexasrepublic]

Re: Help-merc 18 water everywhere

my 70hp Mariner does the same thing... I thought it was normal, ill follow to see. Also FYI add pics, they're better than words, promise.

 

[sylvan14]

Re: Help-merc 18 water everywhere

Took a few pics this morning of the lower unit. Trying to add them.









The water comes out the exhaust and telltale while the motor is running. It also comes out the three small drain holesat the top of the lower unit(seepic 1 & 2(one on each side). The water will also come out from around shift shaft rubber boot(pic 4). When the motor is turned off, water continues to drain out of the 3 small holes in pic 1 & 2.

Any ideas please.

 

[corm]

Re: Help-merc 18 water everywhere

Normal, enjoy!

 

[green4themoney]

Re: Help-merc 18 water everywhere

to verify your problem, you have no problem, these are drain/vent areas so water can enter easier for pump to be primed.... the LU fills with water dam near instantly as its dropped in the water, and its normal when you run your engine on muffs to see water sqirt out of these holes.... nothing to worry about

 

[LOWEMAN 165]

Re: Help-merc 18 water everywhere

Have you taken it out and run it? Is it overheating? If its not ,maybe just run it, and see what happens. As long as you have a good stream at the peehole, and it runs cool, run it.

 

[sylvan14]

Re: Help-merc 18 water everywhere

Thanks for the replies.

I have not had it out yet and have only run it a short bit as the carb needs cleaned & rebuilt. Doing that this week.

I only have one other question/concern on this issue.
If there is enough water pressure in the drive shaft housing, won't it work its way up into the crankcase? Or is the crankcase sealed off from this happening?

I have never taken an outboard totally apart so I do not know how the drive shaft mates into the crankcase and what kind of seals are in this area.

Thanks

 

[green4themoney]

Re: Help-merc 18 water everywhere

the crank case is sealed off, and the driveshaft also has a seal (o-ring) that seals any water to get into the drive splines on the crankshaft.... water exits with exaust from the exaust port from the block of the motor.