1960 johnson lower still leaking

[sheboyganjohn]

I did a rebuild on the lower unit for my boat last year. I replaced most of the seals and skiped the ones that were listed as the pain in the but don't do unless you have to ones. I had water in the lower this spring due to a bad job sealing up the two halves causing one of the bolt holes to leak. I resealed it properly this spring and still had water in the lower unit after the first run. Upon further inspection I found a few drops of oil coming from the tip of the water intake area just below the exhaust port. It seems the oil is coming from the water intake. Any idea of what to look at?

On edit, it is a 40 hp 22-rds

 

[tashasdaddy]

Re: 1960 johnson lower still leaking

did you use new seal washers on the drain and vent screws?

are you sure, it is not this. http://forums.iboats.com/showthread.php?t=207285

 

[sheboyganjohn]

Re: 1960 johnson lower still leaking

I replaced the drain and fill seals the first time I took it apart last summer but not this last time. I figured they would not go bad being used twice in less then two months. I had water in after the first rebuild and after the second reseal. The second time I had it in the drum running a decarb on it so it was run for about 45 minutes total and sat another hour or so in the drum. After that I had close to a 1/2 cup of water in the lower unit. I just noticed a small oil spot on the ground behind the boat after sitting overnight. I touched the drop on the back and it was light brown oil and smelled like gear lube so I figured it was either the shift rod seal or the drive shaft seal. I just want to narrow it down so I don't attack the wrong one.

A bit more history. I bought the boat with a split lower unit I bought a replacement from E-bay which is the one on there now.

 

[Vic.S]

Re: 1960 johnson lower still leaking

Difficult to judge without a diagram
but
If it is definitely gear oil and it is coming from the water intake it could very possibly be the drive shaft seals. Did you replace them and if you did are you sure you put them in correctly.

Not sure if it could be a gasket between pump and gearcase.

I don't know but i don't think a leaking seal on the shift rod will leak oil into the water intake but it could allow water into the gearcase.

As for the level and drain plug washers mine are original (1984) and I change the oil every year! Perhaps it's time I changed those washers as well.

 

[iwombat]

Re: 1960 johnson lower still leaking

Vic, I didn't know you were up north of Hadrian's Wall.

Blow the dust off the wallet and spend a few p on new washers, man.

 

[sheboyganjohn]

Re: 1960 johnson lower still leaking

I don't remember which ones I replaced last year. Guess that is what I get for doing half the job, should have done all the seals then no matter how hard they were to do. As usual I was just trying to get it done in a hurry and get out on the water. I am going to go out to the shed and get out the parts manual and the left over seals and see if I can figure out what I have left. If I cannot figure it out I will just order some new ones.

Thanks for the help.

 

[Joe Reeves]

Re: 1960 johnson lower still leaking

As Vic states..... Oil evident at the water pump intake screen area indicates that the upper driveshaft seals (under the water pump area) are leaking.

 

[sheboyganjohn]

Re: 1960 johnson lower still leaking

Thanks for the clairification Joe. I will get some new seals on order and replace them.

 

[sheboyganjohn]

Re: 1960 johnson lower still leaking

Just a little follow-up. Changed out the drive shaft seal today. When I put the shaft back in I had put some lube on the shaft and as I pushed it in past the lube it created pressure in the case, causing bubbling to come out the shift rod seal. Guess I will be pulling apart the lower unit in the near future and replacing the o-ring.

 

[samo_ott]

Re: 1960 johnson lower still leaking

The other option is to do a pressure test to see which seal is the culprit.

 

[Vic.S]

Re: 1960 johnson lower still leaking

causing bubbling to come out the shift rod seal.

no doubt then if the small amount off pressure you created caused bubbles from there that the shift rod seal is well and truly knackered.

 

[F_R]

Re: 1960 johnson lower still leaking

Half a cup of water in a couple of hours is a major leak. The suction of the water pump can draw oil out the drive shaft seals. That oil has to be replaced by something...that "something" is water being drawn in the shift rod seal.

 

[Evinrude Boater]

Re: 1960 johnson lower still leaking

Chances are you're not the first one over the last 48 years to neglect the shift rod seal. Why would the easy ones be leaking and not the others. Unless you pressure test the unit change everything then you'll know they're all new. And don't forget to replace the spagetti seal.