how to replace prop shaft seal, 1960 40 hp?

[rernst]

Ok, engine runs, took it out to test, now leaking from prop seal.

I have the seloc manual, but I couldn't find details on just changing the seal and o ring on the shaft. Do I have to remove the whole lower unit and disassemble to replace those seals? i'm hoping not.

Thanks,

Rich

 

[freddyray21]

Re: how to replace prop shaft seal, 1960 40 hp?

If the prop shaft seal is leaking the shift shaft and drive shaft seals probably are too. You do have to take it apart, but the good news is it is not such a bad job.

 

[samo_ott]

Re: how to replace prop shaft seal, 1960 40 hp?

Drain the LU oil. Then unscrew the lower skeg (very bottom) and the prop shaft should come out. The seal is on the prop shaft.

 

[Chris1956]

Re: how to replace prop shaft seal, 1960 40 hp?

Rich, If that is a mechanical shift, the very bottom phillips head screw is the shift cradle pivot. It must be removed before the gearcase will open. You need to drop the LU to get at the waterpump seals ans shift rod seals. The lower shift rod unhooks from the upper under the two screw plate on the midsection. You must remove the shift rod clamp screw entirely.

 

[Evinrude Boater]

Re: how to replace prop shaft seal, 1960 40 hp?

You have to disconnect the shift rod to allow the gears and prop shaft to be removed. You might as well take the lower unit off so you can work on it properly upside down on a bench. That way you can observe the order of assembly and you won't have gears and parts rolling out on the ground before you have a chance to see where they go. Be aware there's a bolt behind the mid section cover at the back that's hidden. This must be removed along with the eight bolts that are visible above the anti-cavitation plate. Also of importance is a pin on the upper half of the case that aligns in a hole in the bearing retainer. The seal is removed by puching it out from the opposite side. This is on page 8-43 of my Seloc manual. I have Seloc 1300 manual for 1956-1970 1 1/2-40hp 1 and 2 cylinder 2-stroke models.
Another item to take care of is the drain hole behind the shift rod. This drains the exhaust cavity through a drain hole on the starboard side. This cavity gets plugged up with carbon and dirt from lake water. You have to drill out the foreign material to clear the hole. I have some good photos that are too large to post here. Send me a private message with your e-mail if you would like these photos.

 

[F_R]

Re: how to replace prop shaft seal, 1960 40 hp?

There is an o-ring that goes on top of the water pump housing. Leave that sucker out and tear your hair out trying to figure out why it won't run with the hood on.

 

[rernst]

Re: how to replace prop shaft seal, 1960 40 hp?

Ok, looks like the best bet is to just bite the bullet and remove the lower unit and replace all the seals, etc.

Where's the best (cheapest/most inexpensive... place to get the kit? If online, recommendations please.

Second, I've heard the seal at the bottom of the powerhead is a likely failure point with very unpleasant results, I'm thinking of replacing that while much is apart. Where should I get a replacement for that as well?

Thanks again,

Rich

 

[F_R]

Re: how to replace prop shaft seal, 1960 40 hp?

Seal at the bottom of the powerhead? You speaking of the lower main bearing seal on the crankshaft? That is pretty reliable on that model. I wouldn't persue that unless I had a pretty good indication something is wrong, such as finding pieces of it when removing the lower unit.

Or, are you talking about the o-ring in groove at the drive shaft splines? I 'most always replace that when removing the lower unit, just because it's cheap.

 

[rernst]

Re: how to replace prop shaft seal, 1960 40 hp?

Yes, that's the seal I was talking about, heard it got old and hard and then failed at inopportune moments. If you say they're reliable on such an old motor, I'll not mess with it (less work is good...

yes, I'll find where to get a "kit", I hope, with all the seals I'll need to redo the lower unit, and I believe that includes the O ring at the top of the driveshaft.

now where to get that kit?

Thanks!

Rich

 

[freddyray21]

Re: how to replace prop shaft seal, 1960 40 hp?

right here at I boats http://www.iboats.com/mall/partfind...gd_poid=110561&gd_row=31&**********=704752828

get the impeller while you are at it.
http://www.iboats.com/mall/partfind...gd_poid=109125&gd_row=42&**********=704752828

 

[67Johnson6HP]

Re: how to replace prop shaft seal, 1960 40 hp?

Check the water pump housing too. If it's original it probably needs replacing plus it'll pump water much better.

 

[rernst]

Re: how to replace prop shaft seal, 1960 40 hp?

Great, I'll buy from the folks supporting this forum, excellent pricing too!

Weird about the impeller, I would have expected it NOT to work, or fail quickly after testing, but it's pumping just great. And this after sitting for who knows how long?

I'm not sure why I'd need to replace the impeller housing though, can you explain and why it would pump better if replaced? Isn't it a solid cast part?

Thanks,

Rich

 

[Evinrude Boater]

Re: how to replace prop shaft seal, 1960 40 hp?

The pump housing can corrode and erode. There's a stainless steel plate below the impeller that wears away too. The impeller blades can wear too, especially if started dry or if the motor is operated in murky water and sand is sucked in. If these parts are deeply worn then water escapes by the small gaps and isn't pumped up the tube to the power head. They're inexpensive and easy to replace so it's worthwhile to replace them if there's any question about their condition. I would recommend replacing an impeller that has been "sitting for who knows how long".

 

[samo_ott]

Re: how to replace prop shaft seal, 1960 40 hp?

It's a good point. Last year I changed the impeller on my 18 and it made not much difference (didn't pump in reverse), then I changed the housing (which looked fine) with another I had on the bench and it worked much better.