Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

[frostmonkey]

Became a member of the stupid human trick club on Saturday, when my boat decided it wanted to be on the road, instead of the trailer. As a result I have some minor damage to the lower unit. Basically the bottom front of the torpedo is worn flat. Can this be welded, If not does anyone know of any product to build up the housing where its been worn. I'll attempt to attach some photos.

Thanks

 

[Evinrude Boater]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Welcome to iboats frostmonkey. Too bad your first post is an unfortunate incident. Is the skeg gone too? I've used JB Weld to seal a crack in my gear case and it has held out over two years including wintering in Ontario.

 

[angus63]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Welcome!!!!!
Sorry about your incident.....
Two things concern me
I wonder how much wall thickness remains to a critical component (bearing housing). Also did the impact cause any damage.
You can have it tig welded and shaped,but that much welding may cause distortion to internals, and will cause localized lower temper (strength) in the entire region around the weld.
If it was mine, Iwould find a junk lower unit with a good case, use the internals from your damaged one, and have it resealed in the process. Least expensive way to have a lower unit (like new) that I would have confidence in. I'm sure you'll receive many opinions.
Good luck

 

[angus63]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

If you do decide to build it up with epoxy, be sure to shape it smooth and close to original. You do NOT want cavitation or an assymetric shape that will load up your engine in one direction.
Again Good luck

 

[frostmonkey]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Welcome to iboats frostmonkey. Too bad your first post is an unfortunate incident. Is the skeg gone too? I've used JB Weld to seal a crack in my gear case and it has held out over two years including wintering in Ontario.

No the skeg suffered only minor damage. My concern with the lower housing is what happened inside,and how much wall thickness is left. i priced out a new lower housing today,cost about $1200.00 canadian, and about 500 to swap out the guts. I'm figuring thats a days labour plus materials ( The 500). Not sure if thats a fair price or not. What will happen If I run the engine like it is?

The other question I have is,how difficult is it to disassemble the lower unit and re-install the components into a new housing??? I have the repair manual for the motor.

 

[angus63]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Why new??? There are plenty of junk lowers with prisitine cases you can find for a song. You should be able to find a casing and have it swapped out with new bearings and seals for well under $1000 US dollars.

 

[samo_ott]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

What engine/size is it? And do you have a wider picture of it?

 

[frostmonkey]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Its a 2003 Johnson 90hp, 20" leg,type s gearbox. I do have a wider picture ofthe motorbut the file size is too large to post. I'll try and make it into a small file size.

 

[F_R]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Tell ya what, if it were mine and before shelling out all that dough for replacement I would first peck around on it to see if it is worn thin. It is probably pretty thick in that area. If you don't peck through, you have two options: Leave it like it is if it doesn't cavitate. Or try restoring it with one of the reinforced epoxies like JB or Marine Tex. I wouldn't weld on it. There's stuff inside.

 

[tashasdaddy]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

i agree with F R.

 

[yorab]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Just curious guys: if the damaged area does cause cavitation, then the cavitation erosion zone should be just behind the damaged area, correct? If this is indeed the case, then the drawback to using the damaged gearcase is a bit more damage to the already damaged gearcase. I would think that this would be okay as long as the gearcase is examined each time it comes out of the water (assuming that the wall thickness at the original damage is of a minimum thickness to be structurally sound). Are there other issues associated with cavitation such as fuel consumption or handling that I am not aware of?

 

[Gary H NC]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

I think if it was mine i would try the JB weld before buying a new lower.You can build it up in layers and sand it smooth.Paint it and its good to go.
If you get it close to the original shape it should not cause turbulance in front of the prop.
You could also find a used lower if you look around for 500 or less..

 

[F_R]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

yorab, my intention is not to get a long thread going about what cavitaition and/or ventilation is, but my concern was loss of performance due to air around the prop caused by disruption of the water flow in front of it. I just can't imagine cavitation erosion being an issue on the gearcase metal on a recreational outboard. At least not within the next 10 years or so. I suppose I could be wrong--have been before.

 

[angus63]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

From what I read here and tend to agree:

1) Welding is risky and will cost ya
2) Doing nothing is risky for cavitation and loading
3) Using epoxy is an inexpensive option as long as
a) There is no internal damage now
b) The remaining wall thickness is sufficient
c) It is smooth and symmetric when complete (make a template out of cardboard of the unaffected area and match it as close as possible)
4) Find a used case and swap internals with new seals and bearings. It should be less than $1000 US for everything
5) Find a used or rebuilt lower $1500-$2500 or so
6) New lower unit (You don't wanna know the price!!!!!)

My opinion is go for #4 for pc of mind if your gonna keep the rig
Go for #3 if your a gambler or trading up soon

Good luck

 

[Gary H NC]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

The JB Weld will work fine.There is not much if any stress on it.
If you look around you can find a complete lower for much less than you think.

 

[jtexas]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

ya, take your time, find an affordable case, meantime, break out the marine-tex and have some fun!

 

[mikesea]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

I would try using as is for about an hour,stopping often to check it out,this way,if there was a chance of failure,it would likely show in that hr and not be hidden by epoxy,.I have seen welders perform magic,a guy I used,welded many cracks that develop on some yamahas,no problems after he welded.One trick he used was to keep the oil in the gearcase to help disapate the heat buildup,also rest periods between welds,your situation could probably welded up,as for cost,dont know,personally,I would go with the 1 hr test running and do as the others whom suggested,jb weld or epoxy.Check your oil after each use,in the meantime,if your intending on keeping the eng.look for a used housing.as for swapping the parts,if you can use tools,you can do the work.about the only tool you may have difficulty getting is a large snap ring pliers,I mean big.

 

[frostmonkey]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

So what I've decided to do is.I will temporarily repair the lower unit to get me through the remainder of the summer. In the mean time I will look for a blown lower unit,and through the winter I will rebuild it my self...... I think..... I bought this motor new two years ago and have babied it.... well except for the road rash incident. I intend on keeping it for quite some time, actually I'm looking for a Deep-v hull to put it on. So I don't forsee me selling it anytime soon. I'll keep you guys posted on how the repair works out.

Thanks for all your input!

 

[Harker]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

Do you have insurance?

 

[frostmonkey]

Re: Joined stupid human tricks club!!! Need help repairing lower unit. Road Rash

No Sadly I don't! when I purchased the boat it had a 65 merc 650,on it which blew up the second summer I had it. Thats when I bought the new motor; with the intention of upgrading the hull later. Never considered insurance on the old set up, and never thought of it when I bought the new motor.... Aonther lesson learned!!!! this has been a good week. I've done lots of learning!