[TOBO]

I had this repaired once and within 2 trips it was back to this condition. When I say fixed just had it welded by a reputable shop. So what is it, why is it, how isit and how much to get it fixed? Thanks for your resopnse. If you can only answer one of the questions I still thank you.

it is a 2001 susuki i got in 2002.

 

[alx340]

wher's the weld, i had one welded that lasted over 2 yrs, but it had an 1/2 wide bead on it. i don't see your weld?

 

[TOBO]

It is welded right were the crack is, it didnt have a 1/2 inch top on it. It just filled the gap.I sanded it and repainted it.

 

[Voodoo Lounge]

I would be on the lookout for a replacement gearcase. If the crack moves forward anymore, you'll be calling sea tow!! Let me know if I can help!!

 

[Breeze Fabricators]

I have been welding propellers, lower units and skegs back on for 25 years. The weld had no penetration which is okay as long as you leave some build up on the outside for strength. When you ground the weld smooth you took away the material that was holding the base material together. These cracks are usually caused by the carrier bearing nut being a slightly different alloy than the lower unit casting. Capilarity pulls salt water into the gap between the threads and acts as an electrolyte and causes the nut to swell cracking the case:mmmbeering!

 

[sosmarine]

The metal used in the casting of outboard and stern drive gearcases is very porous and is loaded with impurities. To compound the problem, more crap gets in the crack. I know a couple of good welders that wont touch this kind of stuff. Only someone that has a lot of experience with this type of repair should do it.

 

[Brandy]

If you chamfered the crack it would probably hold without grinding. The impurities are the enemy here. Aluminum and grease are a bad combination for welding.

What caused the crack?

The vertical crack opening up shows some heavy stress. Its always better to chamfer aluminum, alows more surface weld with less heat to original casting. The weld itself is the strongest part of the repair.

 

[TOBO]

I dont't know what caused the crack. So theoverall opinion is another weld , done right, should fix the problem? It does not have any water in the lower unit oil, its not milky.

 

[Downtime2]

I am not sure what the lower unit casting actually is. But, it is cast, not forged metal. I doubt it is 100% pure aluminum. I wouldn't weld it. Unless the penatration and heat are right, it's gonna crack again right beside the weld. The heat transfer on that stuff has gotta suck. Spend the bucks. Do it right. You won't have to worry near as much. I know what it would do to my confidence level dirt dobbering it back up.

 

[user207]

Just my opinion, but I think the proper way to repair the crack will be as follows. NOTE: I have welded several of lower unit cracks over the years. It all comes down to how its done, and how much money the custom is wanting to spend to get it fixed. (1) Remove lower unit. (2) Remove propeller (3) Remove aluminum flang nut. (not sure if that is actually what it is called) (3)*Optional, but reccommend* Remove main propeller shaft, and seals, clean thoroughly (4) Clean all carbon deposits on the inside of the housing, and paint on the outside surrounding the cracked area. (5) Find the end of each crack. NOTE: Sometime you have put a little bit of heat on the cracked area, this will open up any hidden cracks that may not be visible. (6) Once you have located all the cracks, drill a small hole (3/16" approximately)at the end of each crack. This will prevent the crack from growing any further during the welding process. (7) Grind each crack thoroughly, making sure that the inside is ground down also. (8) Insert copper flange nut. (This will need to be fabricate by someone who has access to a lathe), this copper piece will prevent exessive damage to the internal threads. (9) Weld repair outside of the housing. Also weld what you are able to access on the inside. Be sure to allow time for the part to cool down before attempting to remove the copper flange nut. (10) After the flange nut is removed, weld the rest of the damage area. If there is any damage to the internal theads, then use a pencil grinder with the proper bit to manually cut the threads until the original flange nut can be reinstalled with out any binding. (11) Everything should now be ready for re-assembly, painting.

 

[Halfmoon]

In my years abusing engines and lower units commercial fishing, Once you crack the gear housing its done.

I have welded them to only either, have it crack agian, or the housing expands where the gears do not sit in the housing true and you eat up the gears. Looks to me you need a new foot!!

Good luck! You can try it, but I can tell you, it will be a problem.

 

[jhall]

I had the same thing happen a couple years back to one of my motors. I caught mine when it was about half the size of yours. I drilled a small hole at the end of the crack and that solved my problem. I fished for about 2 more years with no more cracking. I never did weld the crack. I think you need to at least drill a hole like Tim Barry mentioned in a previous post.