crack in lower unit

[scott craven]

Has anyone successfully repaired a cracked lower unit I've heard about J.B Weld epoxy, would it work ?
Or could it be welded ?

 

[daddystoy]

WOW! That is nasty looking. Is that were the prop shaft goes in? You must have hit something to do that. Personally I would be pretty hesitant to do either of those suggestions.

 

[profisher]

What motor is that?

 

[ComfortZone]

I think that housing is designed to have bearing races pressed into it, the housing is spread now, so even if welded you risk spinning the races further damaging the housing and internal parts...sorry to say but me thinks that housing is toast... maybe others have had experience repairing??

 

[scott craven]

What motor is that?

50hp Honda

 

[profisher]

Lots of those around, I would put a wanted ad in used vict for a not running parts motor. You would get a gear case and an easy swap plus some spare parts.

 

[SteelyDan]

Weld it.............

 

[Califbill]

I would see about welding it. Maybe a good propeller shop. As you need the case hole to be the proper size to hold the bearing and seals.

 

[GDW]

Depending on cost I'd try to fix it. Worst case it doesn't work and you end up needing a new Lower unit - which you need at the present time anyways. Do you know the cause or was that a surprise?

 

[bigdogeh]

I had a 50 horse merc lower unit tig welded years ago. damage was done from water freezing I believe. welding it worked for the life of the lower unit. got another 10 years or so out of it.... wasn't cracked in the same area as yours but i would attempt having it done. if you get it done, leave the full weld rather than having it ground down to try to look pretty. it'll be stronger that way. and of course, remove all the guts, etc and clamp it so the crack is pressed back together before having it welded.

 

[KV1]

Depending on cost I'd try to fix it. Worst case it doesn't work and you end up needing a new Lower unit - which you need at the present time anyways. Do you know the cause or was that a surprise?

Absolutely! Not much stress threre and a good weld will last forever. Lots around just ground down and painted.

 

[fishin solo]

weld it up but make sure they preheat it first and it will be good to go

 

[scott craven]

Depending on cost I'd try to fix it. Worst case it doesn't work and you end up needing a new Lower unit - which you need at the present time anyways. Do you know the cause or was that a surprise?

Was a surprise to me, although there was a small ding in the prop as well.
so much crap floating in the water.

 

[Sr SQ]

Are you getting any oil leaking or water in the LU?

I have successfully welded many LUs over the years but you are going to need a tig welder.
If no leaks, then its just in the exhaust hub…..lucky, there is likely a large seal ring inside that holds the brg and seal assembly in I would leave this in place as it will help lessen the warping from the heat.
I would grind a v notch ( aprox 1/2 the thickness deep) along the crack then get a couple of band clamps on the hub to see if you can close up the crack a little.
Starting at the base of the crack (towards the nosecone) I would start with a 1/2" back stitch and get off it till it cools, repeat till you get to the end.
Problem with taking it apart is its going to warp and you may need to machine it true after in order to true up the brg and seal surfaces, this will likely make the repair more than the cost of a replacement housing.
If you weld it assembled and your careful with the heat you may not damage the seal enough for it to leak, its worth a try.

If you have to replace the LU do not buy an offshore replacement they are absolute garbage in my experience, find an OEM part if you can

 

[profisher]

Not sure if you can do this to keep heat from taking out the seal. I had a customer who replaced carbide tips on oil drilling bits. it was done with the bearing section submerged in water to keep it cool while welding. If the bearing got damaged the bit was junk.

 

[Sr SQ]

Yeah maybe but I get lucky most the time………..
Like already mentioned, theres not much to loose.
Disassembly,welding,machining and reassembly could make the repair not cost effective if you need to pay someone to do it?
Welding it assembled give you a chance, if you do take out the seal out…….. oh well you would have replaced it anyway from the disassembly.
I make sure theres oil in them and take it slow….real slow, crank your amps up get on it hard and get out early, keep your stitches down to 2-3 puddles (1/2") or less then wrap a wet towel around the seal area I am trying to protect and let it cool right down. It can take me a day to do 10min of welding.

 

[Sculpin]

Yeah maybe but I get lucky most the time………..
Like already mentioned, theres not much to loose.
Disassembly,welding,machining and reassembly could make the repair not cost effective if you need to pay someone to do it?
Welding it assembled give you a chance, if you do take out the seal out…….. oh well you would have replaced it anyway from the disassembly.
I make sure theres oil in them and take it slow….real slow, crank your amps up get on it hard and get out early, keep your stitches down to 2-3 puddles (1/2") or less then wrap a wet towel around the seal area I am trying to protect and let it cool right down. It can take me a day to do 10min of welding.

Sounds like a great procedure. There is the slight chance of screwing up the internals if not grounded properly when welding. Other than that and the seal, he has nothing to lose.

 

[scott craven]

Had a very kind offer by a fellow forum member to weld the crack so I
dropped the lower unit this morning and took it out for service.
I am always thankful for the good folks here that help each other out.

 

[scott craven]

Nice job Dan....

 

[Fish Assassin]

Very interesting........ Fingers crossed