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Pwoida
27-04-2006, 10:27 AM
Pulled the water pump off my 1978 Evinrude 115 and found the drive shaft to have pitted around the water pump area. How bad is it? I had one engineered years ago but I can't remember what state it was in to need repair.

Pwoida
27-04-2006, 10:29 AM
.

blaze
27-04-2006, 10:51 AM
they lathe off about 1mm (or more depening on damage) then use a spray power to build up (like blowing molted metal back on) then machine off and grind to original finish. Any good engineering shop should be able to do it for you
cheers
blaze

Pwoida
27-04-2006, 11:16 AM
I've had it done before, but what I'm trying to gauge is how bad does it need to be before going to that extent?

blaze
27-04-2006, 01:58 PM
It needs doing
It only takes the smallest burr/chip to take the sealingedge off a seal in one single turn. Rule of thumb, if you can feel it with a fingernail it needs doing and you can feel things with your nail that are only just visable
cheers
blaze

blaze
27-04-2006, 04:53 PM
Its not going to let water into your gearbox but from looking at my manual there is a o'ring and a grommet there?, these will not last long (about as long as it took to put them there) if the damage is not repaired. Dont believe this would have any depremental effect on the longjepity of your motor. If it was mine, I would repair.
cheers
blaze
Ps
I suppose it boils down to cost, can you dismantle the box yourself.

Pwoida
27-04-2006, 05:17 PM
As far as I know from working on other OMCs is that I shouldn't have to dismantle the box to get it out. If I do then I'll probably just run the motor until I do find water in the box and then upgrade, but I should just be able to pull it out without too much dramas from memory and get it to the engineering shop. Better to have the job done properly i guess.
Thanks for your help.

Peter.

Pwoida
01-05-2006, 07:22 PM
I've just bolted my lower unit back on after doing a rebuild on it and I'm getting some water leaking out of the join where the lower unit meets the upper leg. Everything else seems fine, there's a strong tell tale, exhaust seems ok, I tightened the bolts to torque specs., but there's some water leaking out of the join. Spraying out in some spots. I don't think thats normal is it?

catchy_fishy
02-05-2006, 05:06 AM
they lathe off about 1mm (or more depening on damage) then use a spray power to build up (like blowing molted metal back on) then machine off and grind to original finish. Any good engineering shop should be able to do it for you
cheers
blaze

Pwoida

Following on Blaze's advice, a painful solution but one that will work, all be it for a while, is to sand it down with water sandpaper - very fine grain.

I had to do this with a seized wheel bearing on my shaft in my landy, during one XMAS when all the engineering shops had closed.

The problem is that if you are not careful you can remove more than the required amount, and the seals end up not sealing properly. It was Ok on the landy to take off a little too much, as I don't go in water that often with her, but on your pic you might need to get it done properly - by the look of it itr needed doing a while ago.

Hope it's not too expensive.

Mike

Spaniard_King
02-05-2006, 07:58 AM
Pwoida,

what did you end up doing with the shaft :-/??

What sort of rebuild did you do?/

Garry

Pwoida
02-05-2006, 09:13 AM
After recieving advice from various sources I decided to leave the drive shaft as is and install a new water pump kit and new drive shaft seals in the upper bearing housing. The problem that made me pull it apart in the first place was some sort of blockage resulting in no tell tale. That turned out to be a damaged water tube grommet.

Anyway, it all seems good so far, I was just wondering about the water coming out of the join where the lower unit bolts back on as I've never noticed it before, but I've now been told that it's not unusual to get that as there is no gasket on that surface.

As far as the shaft pitting goes, I'll wait and see if I get any water in the gear box but technically, so I've been told, the shaft wear around the impellor shouldn't affect the drive shaft seals which are below the impellor plate and underneath the upper bearing housing.
Fingers crossed.

If anyone is interested, I got some of my info from an american forum dedicated to outboard repair, which has a resident expert for most brands of outboard. PM me for details as I don't think I should post the link here. I also got great info from you guys and from my recently purchased manual on a CD off Ebay.

seatime
02-05-2006, 07:12 PM
Hi all, I read some interesting info on stainless steel recently. Stainless has an oxidised layer on the surface of the metal created by the chromium reacting with oxygen. When this hard outer layer is buffed and polished the underlying metal becomes corrosion resistant. When immersed in oxygen rich water the corrosive resistant layer is actually enhanced.

Pwoida, what has happened with your shaft is, it has been starved of oxygen underneath a rubber seal and corrosion has caused the pitting.
It appears there is no easy way to avoid this other than maintenance and regular inspections.
cheers Steve.