1998 DF70 hairline crack in foot near hub

[18pontoon]

There is a small crack about 1" long less than 1mm wide in the foot near where the prop attaches in my 1998 DF70. It does not cause any oil leakage from the lower unit but I don't want this to grow any more.

Can it be TIG welded? A friend recommended I try aluminum welding rods from harbor freight Aluminum Welding Rods - Pack of 8 Low Temperature Rods.

How would you suggest fixing this crack. I'll take pics next time I'm on the lake.

[BillCon]

If, it was mine, I, would just take the foot off and take it down to a welding shop that can weld aluminum and get it fixed right the first time to keep it from spreading, its not that expensive for a professional repair, maybe $50

[18pontoon]

Thats what I was thinking. I can remove the foot in the off season and have it fixed properly. Also I can clean up the paint and replace the water pump while I'm at it. Should any of the gearbox components be removed to help prevent heat damage or could this be repaired with everything inside the foot left intact?

[BillCon]

I, dont think so, because they woulnt get the case that hot, I, had a yamaha 115 that had a 4" crack fixed it ran right up to the outer seal, they just welded it in stages and it was fine, those low temp aluminum rods woulnt stick, I, tried that with no success.

[18pontoon]

Great info... Couple of more things. The very bottom of the skeg (lowest part of lower unit) is missing about 1" of material that broke off. Should I look into getting that bit of material replaced or not worry about it?

Also how would you recommend repainting the lower unit? Sandblast and scrape off old paint then repaint with this paint from Browns Point? ColorRite - 4650 - Suzuki Shadow Black Metallic Paint

Primer? The motor was run in salt water for many years so the whole lower unit could use a repaint job.

[Solarman]

welding

The bottom of the skeg can be ground and shaped, or can buy replacement skeg,(~$25), cut off how much is missing and whoever does the aluminum welding can replace that part/piece when welding, as well as shape it.

As far as painting, I would scuff up the existing paint (not sandblast or remove), with one of those green scruffy pads, and make sure all grease/oil is cleaned off, then take a few cans and spray it, one light coat at a time, until you get it covered well. I've had great results with those cans, without having to prime.
Tape/ cover those parts, or remove those you don't wish to paint. Prop, prop shaft, zincs, water inlet screens, etc.
Good luck

[BillCon]

If you happen to go thru to the bare aluminum when prepping your lower unit just use a primer made for aluminum thats no problem I, paint all the time, just remember dont leave bare metal exposed more than 6 hours before priming, it will start to oxidize then the paints dont bond and will start to peel, and like solarman said just reshape the skeg or get one of those skeg repair kits

[18pontoon]

Finally getting around to doing some of this work. What is the difference between the charcoal gray and shadow black? How do I tell which color is on my outboard?

[BillCon]

I, heard somewhere Suzuki used shadow black metalic, but it may not match the original anyway due to paint fade, I, always do a total repaint just to do it right, doesnt cost that much more and maybe a couple more hours prep time but its worth it in the long run.