Water on bottom spark plug and the oil on the treads look milky?

[Michael leblanc]

What causes this and it's a 1979 mariner 25hp

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

Forgot to tell y'all it starts up second crank and runs awesome

 

[oldman570]

Re: Water on bottom spark plug and the oil on the treads look milky?

You can get the water if the exhaust housing center plate is cracked or has a pin hole from corrosion and heat from the exhaust. The gaskets for both the housing an divider plate can be bad also. You should remove those and do repairs as needed, or the motor will be damaged if not repaired. JMO
Olman570

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

Ok now that u say that the gaskets look old and rusted like it would be bad I seen they don't make the gaskets anymore can I just buy gasket material for exhaust and cut it out would that work?

 

[Faztbullet]

Re: Water on bottom spark plug and the oil on the treads look milky?

If its a 79 model it the yamaha branded engine and it has a head gasket that can leak...

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

Yeah it's a 79 model I was looking at motor yesterday and where the exhaust gasket is on side the motor it is all rusted and crusted up my head gasket looks good I'm thinking its my exhaust gaskets but they don't make them anymore can I make the with exhaust gasket matiral

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

Head gasket would causes this too?

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

??????

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

Ima change head gasket and see if that works first

 

[Chris1956]

Re: Water on bottom spark plug and the oil on the treads look milky?

What about the lower crank seals? If they leak you get water in the lower cylinder.

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

Idk

 

[Michael leblanc]

Re: Water on bottom spark plug and the oil on the treads look milky?

It's not alot of water but its a little milky on just bottom plug...where lower crank seal located

 

[Chris1956]

Re: Water on bottom spark plug and the oil on the treads look milky?

On a standard merc, the lower crank seals are in the lower block end cap. Of course I could not find a listing for a '79 Merc 25HP motor. There was a 20HP and 40Hp versions.

 

[carholme]

Re: Water on bottom spark plug and the oil on the treads look milky?

It is a Mariner engine, made by Yamaha for Mariner:

25 M 695-000101 - 695-003445 1979

Parts List for s/ns 695-000101 thru 695-023895:

MARINER 25 - Mercury, Mercruiser, Force, etc. Parts Lookup

See lower crank seals, item 13 under CRANKSHAFT AND PISTON.

Mariner outboards are identified by engine
serial number. This number is stamped on a
plate riveted to the transom clamp. It is also
stamped on a welch plug installed on the
power head (Figure 1). Exact location of the
transom clamp plate and welch plug varies
according to model.

I am working on getting you the condensed version of the Clymer manual which is buried under a larger file. Can you PM me an email address that I can send information to you?

Gerry