Hi, I bought an old tri-hull with a 1987 70hp Evinrude. The lower unit was cracked, pics below. I found a replacement, but the driveshaft I need is 4 spline and the one I found is 16. Does it look like this one could be welded or is it shot?
There is more to it then welding that.---It appears to be due to freeze damage and it was full of water.----And welding aluminum castings often distorts them and then on reassembly thing will not fit / go together.----------If you weld it before taking it apart then it may not come apart if you need to !!---Internals are likely rusted ?
Your need to get a lower unit from a 1978 to 1988 model 3 cylinder. The 1989 and later models have different lowers and more splines on the shafts and I believe the casting is different. They don't interchange
Once a case cracks like that, it may wind up distorted internally. welding it will just set the internal mis alignment and cause other problems. Scrap it.
OK, in that case I'm going to grab that other lower unit and try to swap the shafts, I have a service manual, looks like I'll have to track down a few OMC special tools, best place to do that on ebay?
