holy cow!! hit a rock today and broke the fine under the prop clean off

over there · 20 September 2008, 02:46

so i was out in halifax harbour today and was ripping around all day having a good time. then i my way back i smacked clean into a rock with my 40HP mercury and broke the fin under the prop clean off. haha not impressed at all, however the prop only has a little nick in it and it still drove home fine haha. does anybody have any idea as to what i can do to fix it or if i even need to have the fin put back on? lesson learned, stay away from the shore when driving at full speed during low tide! any one know where i can buy a good prop, cuz i have hit a few times before and probably need a new one. thanks

spartacus · 20 September 2008, 09:06

Quote:

then i my way back i smacked clean into a rock with my 40HP mercury and broke the fin under the prop clean off.

That'll be your skeg then. You'll need to find a repair shop that can do an aluminium weld using MIG welder. Only trouble - is that the heat can cause gearbox issues due to distortion. Would mean removing gearbox and oil to safeguard rubber seals. See link.

http://www.outboardrepairs.com/topics/011057.html

You can use the outboard without the skeg, but it's there to offer a degree of protection for the propeller. I'm sure it helps with tight turns too.

If there's enough of the skeg left you could bolt on another. Seems a few people have done this.

Stoo · 20 September 2008, 13:51

I'm sorry to say that I have done this more than once. My local Yammy dealer buys skegs from Yamaha, welds them on, paints them up and it's good as new. I dont recall what he charges me (haven't done it in a long time...) but it wasn't a lot.

All this assumes you didn't bend the shaft, but it doesn't sound like it. The prop can be touched up usuall for minimal cost.

I am going to try very hard not to use my new engine as a bottom sounder...

Nasher · 20 September 2008, 20:50

TIG welding would be far more suitable.

I think MIG welding a skeg would be near impossible.

Nasher

BogMonster · 20 September 2008, 21:10

I thought I read somewhere recently that you could only TIG or gas alli, but I might be wrong...

Nasher · 20 September 2008, 23:32

You can MIG Ali but the amount of power required is quite large.
There are probably other reasons which somebody far more knowledgable than me will let us know.

I have welded thin(2mm flat bar) Ali myself with my MIG using a reel of Ali wire, and I think it was Argon gas.
The main trouble was the soft Ali wire didn't like being pushed up to the gun, and would sometimes bunch up just after the pinch rollers.
Probably my technique more than anything.

Nasher.