1993 Mercury 40hp Classic Water in Bottom Cylinder and Crankcase

[ptochman]

I have a 1992 Mercury 40hp Classic 2 stroke 4 cylinder that ran great last year. This year it was hard to start. I found water on the spark plug for the bottom cylinder and removed the exhaust cover and found milky water in the crankcase.

How do I determine where the failure is? How do I clean the crankcase?

I will attach pictures. I have not done anything at this point. Your help is appreciated.

I thought I could order a Sierra 18-4325 Powerhead Gasket Kit for starters.

 

[ptochman]

I have a 1992 Mercury 40hp Classic 2 stroke 4 cylinder that ran great last year. This year it was hard to start. I found water on the spark plug for the bottom cylinder and removed the exhaust cover and found milky water in the crankcase.

How do I determine where the failure is? How do I clean the crankcase?

I will attach pictures. I have not done anything at this point. Your help is appreciated.

I thought I could order a Sierra 18-4325 Powerhead Gasket Kit for starters.

Compression is 125-125-120-120

Here are pictures of the exhaust baffle.

 

[Faztbullet]

Replace bottom seals on powerhead

 

[ptochman]

Replace bottom seals on powerhead

The crankshaft seal(s)?

 

[racerone]

Correct there are 2 oil seals on bottom crankshaft bearing housing.---Replace them and perhaps the bottom ball bearing as well.

 

[ptochman]

Any tricks to getting the crankshaft end cap off? I got the 3 bolts loose and tapped it with a wooden stick and a hammer but I am leary of hitting it too hard.

Also, no emulsified oil and water around or in the end cap. Still change the seals? The powerhead gasket has what seems to be a lot of carbon buildup and a crack in the gasket by the driveshaft.

 

[ptochman]

I found a post by emckelvy to remove the end cap.

How do I clean and protect the inside of the engine?

Thanks for the help guys!