Lower unit hair line crack!

[leech~~]

Pulled the boat off the lift for the year and when it was sitting in the yard I noticed a wet spot on the lower unit. Looking closer I found about a 3" hair line crack that was leaking water and oil. I didn't notice it all year or when I changed the gear grease this spring. Anyone know of a good place around the metro that can do some repair work on them?

[CAMAN]

In my experience, welding cast aluminum is very difficult to create a complete seal and may create stresses and more hairline cracks while doing so. Also putting that much heat on the housing could possibly warp it and cause damage to the bearings.

Not saying you should or should not try repairing it, as I have not seen the crack in question. Just giving you a word of warning that you could be throwing money at a potentially irreparable problem and maybe looking at finding a new or used housing or lower unit assembly may be cheaper and less hassle than repairing.

[delcecchi]

Depends on the value of the motor. If it is old, I would be tempted to grind a little groove along the crack and give it a shot of JBWeld. Maybe drill a little stress relief hole on each end of the crack first. Or get it welded, if it doesn't work you aren't out much and can still put on the new lower unit. Or buy an new motor.

[leech~~]

Depends on the value of the motor. If it is old, I would be tempted to grind a little groove along the crack and give it a shot of JBWeld. Maybe drill a little stress relief hole on each end of the crack first. Or get it welded, if it doesn't work you aren't out much and can still put on the new lower unit. Or buy an new motor.

She is a 1993 75 Merc so I will be trying anything before replacing the lower unit! JB maybe the way to go?

[delcecchi]

Got boat insurance? You might have hit a rock.

[kfk]

Take it to a professional welding shop and get an expert to fix the crack. I did it years ago on a motor I once had and it worked great. If it's electric start and it's to be welded, make sure you disconnect the battery cables to avoid issues on your motor. I had a skeg welded once and when I got the motor back, I had wires burned off inside the engine compartment because I didn't do it, assuming that the repair guy would before he welded it.

[leech~~]

Take it to a professional welding shop and get an expert to fix the crack. I did it years ago on a motor I once had and it worked great. If it's electric start and it's to be welded, make sure you disconnect the battery cables to avoid issues on your motor. I had a skeg welded once and when I got the motor back, I had wires burned off inside the engine compartment because I didn't do it, assuming that the repair guy would before he welded it.

del, not much chance of hitting a rock in Lake Edwards since I only fish deep and the lake is mostly sand. kfk, thanks for the advise. I knew people had skegs fixed so I wasn't sure why they could run a small bead down it? I do have until next spring to get it fixed.

[BartmanMN]

I think del was saying that with a "winky" smile

[delcecchi]

I think del was saying that with a "winky" smile

Hey, there could have been a rock... or a log. Yeah, I guess I should have put the winkie on there. At least I didn't say it could have come loose and fallen off in deep water.

[Northlander]

Jay Soderbloom does real good work if your over in the Cromwell area ever.

[leech~~]

Hey, there could have been a rock... or a log. Yeah, I guess I should have put the winkie on there. At least I didn't say it could have come loose and fallen off in deep water.

Aaah, I'm a little slow at times. Actually the landing is a little rocky and shallow! Huum, where did I put that Allstate number again!

[harvey lee]

Depends on the value of the motor. If it is old, I would be tempted to grind a little groove along the crack and give it a shot of JBWeld. Maybe drill a little stress relief hole on each end of the crack first. Or get it welded, if it doesn't work you aren't out much and can still put on the new lower unit. Or buy an new motor.

No doubt the JB weld would work here. As stated, make sure to drill a small hole in the end of the crack and that way, it should stop it from going further.

After you have it done, I would flush the lower unit just to clean out any alum filings from drilling the holes if any dropped into the lower unit. Seems minor with alum filings but no need to take any chances.

[leech~~]

Thanks Hav for staying up so late to give me some ideas! Since it is a older motor I will be trying the easier fixes first and then try the weld idea. Then, start working on the wife for a new motor! Wish me luck on that!

[Whoaru99]

I've seen Loctite 290 used to seal small cracks and porosity.

It's a thin, wicking liquid generally used to seal/lock already assembled fasteners but will wick down into a crack or porosity area and seal it.

Might be worth a try.

[leech~~]

Well now I don't know what to think? I pulled the drain plug and only pure gear lube came out with no water at all? Not sure if it is a crack or just a nice scar? Any one that has gotten water in their lower unit, did it come out milky? I had no water at all come out.

[CAMAN]

Usually the lube is only milky for a day or two after it has been run. If it sits for a while the water and oil separate and when it comes out can look fairly normal if there isn't a ton of water.

[leech~~]

Usually the lube is only milky for a day or two after it has been run. If it sits for a while the water and oil separate and when it comes out can look fairly normal if there isn't a ton of water.

That is the odd part I found no water inside the housing? Unless, the water being thiner then the gear lube leaked out and only the gear lube remained! [PoorWordUsage]!

[Bambito]

I had the same exact thing happen to me. I bought the motor (82 25 hp johnson) from a guy. Got it home and noticed a horizontal hairline crack about 1.5 inch long.I took a little grinder and grinded the entire crack about 1/16th of an inch deep...NO MORE! Took some JB weld (Marine) and gooped her up real good! Took it to rainy lake this year and it sat in that lake the whole week and ran all over heck! havent had a problem with it yet!