Drain hole,Seep hole,water leaking from powerhead

[JDB123]

From a previous post about the impeller.

I installed a new impeller and after putting everything back on i lowered the motor into a tub of water and fired it up. Everything was perfect.

I pulled the cowling off and notice some water coming out of a hole by the top spark plug. After inspecting the motor it appears this has/was doing this for a while even before i aquired the boat from my father. Im not sure that this is a normal function however it does look like a normal function of the motor.

I also removed the water jacket on the back , this hole is not part of the jacket.
I have removed the plugs and all look good with no sign of water.

My manuals tell me of two ways to check that the water pump is working, one is the tell/tale and the other is the exhaust relief hole. Is this the exhaust relief hole?

Now im no expert but i did stay up for 5 hours reading the seloc manual (Yes the big thick one for my engine) and i did not find one mention of this hole in the entire book.

Could someone who may have some experience in this tell me what the cause of this is or is it normal?

I did see some pictures in the manual where water was coming out of the lower vents for the upper cowling, on some earmuff shots of some Mercury's and thats exactly what mine looks like when i have it turned on.

Also would like to add, the motor has never been over heated and is currently not getting hot.

1986 Mercury Classic 50,45hp

 

[Laddies]

Re: Drain hole,Seep hole,water leaking from powerhead

Thats not a drain or weep hole it's for a temp sender,chances are the water jacket cover gasket is whats leaking a very common thing on those engines

 

[JDB123]

Re: Drain hole,Seep hole,water leaking from powerhead

there is no threads on this hole, and it is not even connected to the water jacket.

I can remove the jacket completely. Actually replaced the gasket on it less than 24 hours ago.

I can also take a pencil and stick in the hole and know that the water is indeed coming from the hole and not the water jacket housing around it. Maybe i might be misunderstanding but what i believe is the water jacket is what you see there with the ten bolts in it. This hole in question is in the same part of the motor that the plugs are screwed into, not the jacket.

Now if this is indeed a hole for a sensor, such as the one below it with the plug in it(on the water jacket). Can i attatch a plastic fitting into it with a hole and have it drain out the vent below and have no worries?

Thanks for your response

 

[j442w30]

Re: Drain hole,Seep hole,water leaking from powerhead

I have the same 4 cylinder (1993 classic 40 horse) head like yours and on mine its for the temperature switch which is different from the sender for a water temp or pressure sensor which goes in the bolt between cylinders 2 and 3. If yours is not threaded then it must be for something else but I would not want water coming out of it and just emptying into that area. You could tap it out and plug it with a bolt and some teflon tape. Maybe someone else on this forum knows what it for specifically though.

 

[Laddies]

Re: Drain hole,Seep hole,water leaking from powerhead

If the water is actually coming out the hole then there must be a crack into the water jacket, it can't be that the hole is to deep as it would be going into the combustion chamber so if it were mine I would try to seal the hole with some type of filler and hope for the best

 

[JDB123]

Re: Drain hole,Seep hole,water leaking from powerhead

I talked to an old friend tonight about this. He told me that there is a gasket in this hole that when left dry over a period of time it will shrink up. After it has been re hydrated it expands and closes back up. Said it should seal back up after running it for a while.

Told me its perfectly normal for this to happen when a boat has set for a period of time for this motor. Which makes me feel very good.

I want to thank all of you who posted to this, but i wanted to share the solution in case someone else like myself is on here looking for an answer to this same problem.