1960 Johnson 40 HP Prop Shaft Seal

[jleiii]

New poster here, hoping someone can clarify this for me, and maybe I can return the favor in the future.

I just put this engine (RDS-22) back in service after having it in storage for 25+ years. I had my marina do the tuneup, carb, fuel pump and impeller, and I took it from there. Got it all set up on a 1970 Boston Whaler Sport 13, and have been using it for a few weekends now. I noticed last week a puddle of oil appeared below after sitting. The smell test indicated gear oil. I suspect the seals have failed due to age, and using it has caused it to leak. It did not drip a drop in the 25 years I've had it, as far as I know.
We took it to MD this past weekend, and now it's really leaking. The oil is crystal clear, so no indication of water in it yet. We ran it for probably a couple hours total over this past weekend. I looked at the docs I have (parts diagram) and there looks to be an oil seal and retainer behind the prop, but I have been unable to identify if this can be removed without dropping the bottom half of the gearcase. I assume it's screwed in as it has 2 pin holes typical of screw in retainers. Am I on the right track, or is disassembling the whole gear case the only option?
I have a spare lower unit that I will practice on before I tackle the leaking one. I've searched here and read dozens of posts, but no mention of that retainer, only dropping the whole unit and taking it apart.

Regards, John

 

[kfa4303]

Re: 1960 Johnson 40 HP Prop Shaft Seal

Hi J. Welcome to iboats. Here are some handy links to walk you through a reseal job. You can get the reseal kit itself right here at iboats, or from marineengine.com for about $25. The kit contains several oil seals and o-rings that are used to make the gearcase watertight. Each kit generally included an oil seal for both the drive shaft and prop shaft as well as o-rings for the top of the drive shaft, the small phillips head screw on the gearcase, one for the lower shift shaft rod, the spaghetti seal, as well as the two white, nylon crush washers that do on the DRAIN/VENT screws. You may want to check these first. They can be replaced for a few bucks and may solve your leak. The only special tools you need are an oil seal puller (about $7 at any auto store) and a tube of 3M 847 gasket sealant, which can be hard to find, but is available online, if need be. The job it self is pretty straight forward, but can be frustrating if the seals are stuck in place. Just take your time, use lots of penetrating oil and take care not to damage the relatively soft aluminum housing the seals are found in. Good luck. Holler if you get stuck.


http://www.marineengine.com/parts/v...ntage-evinrude-johnson/378128/37812800001.htm

http://www.duckworksmagazine.com/04/s/columns/max/24/index.cfm

http://forums.iboats.com/showthread.php?t=277190&highlight=lower+unit+seal+kit+installation

 

[jleiii]

Re: 1960 Johnson 40 HP Prop Shaft Seal

KFA4303,

Thanks. I've had the parts diagram for some time, and already found the other 2 links, but neither mentions or shows the prop shaft and/or retainer & seal (3rd link is broken on going to page 3). I suppose I should just do the whole thing regardless, but still don't understand how to access the prop shaft seal.
I guess I should just tear down the spare I have and see how it goes. Maybe it will be obvious.

Here it is just before the first launch. Not too bad looking considering it's 52 yrs old. The BW was overhauled too. The outside gelcoat was totally ground off, faired and has 1 coat of gelcoat. The interior was also ground down, but not all the gelcoat was bad. It's sprayed/faired with resin & ground glass to strengthen the surface. Both will get 2 coats of gelcoat after the season is over.

 

[lindy46]

Re: 1960 Johnson 40 HP Prop Shaft Seal

You have to drop the lower unit and remove the skeg to access the propshaft seal. You'll have to remove the Phillips head shift yoke pivot to get the skeg off. Once the skeg is off, the whole propshaft/bearings/gears and bushing can be lifted out of the gearcase. The seal is mounted in a bushing and the assembly slides off the end of the propshaft. I usually use a nail punch to knock the old seal out of the bushing. There may be two holes on the backside of the bushing to accomplish this.

 

[kfa4303]

Re: 1960 Johnson 40 HP Prop Shaft Seal

+1. When you drop the LU and split the two halves of the gear case, you'll see the bearing that the prop shaft passes through. The outward facing surface is recessed and the oil seal is seated in place. There is also an oil seal found below the water pump housing late that the drive shaft passes through.

 

[AlTn]

Re: 1960 Johnson 40 HP Prop Shaft Seal

just as an observation, it's been my experience that old fuel mix/ carbon mix get diluted when an engine is brought back from nonuse. This mix drips from the exhaust down onto the prop and propshaft housing and makes it difficult to determine the source of oil spots. I taped on a piece of aluminum foil shaped to fit the exhaust "snout" to help determine the source. It allowed the mix to flow out further than the prop so I could rule out the propshaft seal. If you've already determined it to be lu oil then disregard this advice.

 

[jleiii]

Re: 1960 Johnson 40 HP Prop Shaft Seal

just as an observation, it's been my experience that old fuel mix/ carbon mix get diluted when an engine is brought back from nonuse. This mix drips from the exhaust down onto the prop and propshaft housing and makes it difficult to determine the source of oil spots. I taped on a piece of aluminum foil shaped to fit the exhaust "snout" to help determine the source. It allowed the mix to flow out further than the prop so I could rule out the propshaft seal. If you've already determined it to be lu oil then disregard this advice.

It's gear oil, no doubt. Looks and smells like it, and it's only dripping off the prop.
Tried to open the spare unit I have last night, but impact bits were MIA. Ordered the seal kit (sorry iboats, out of stock) and hope to have it by the weekend. My son's already sweating it!

Thanks all for the help. I'll post again when I get it done.
John

 

[jleiii]

Re: 1960 Johnson 40 HP Prop Shaft Seal

Got the seal kit over the weekend, made a shift rod seal remover and went to work. Got the lower unit off, opened it up, and aside from it being clear this motor did time in salt water, everything looked good. We took apart the 'spare' unit first to make sure we understood what we were doing, and in the side by side comparison, the original is now the spare. The water cavities in the spare were like new, the water pump cover and impeller were brand new, but the water pump seal was damaged. My seal and impeller were also new, but the cover was just too corroded to consider. Seal on the way, and maybe we can have it ready by the weekend.
My nephew recently traded (even up!) a 17' bow rider for 21' cuddy cabin, and also expects to be in this weekend, and with the Red Bull Flugtag in town on the Delaware, I think the BW will be forgotten by them for now. John