Outboard Foot Repaired with JB Weld

2014-08-03 written by: Brad

$3.00 in JB Weld and scrap aluminum sure beats the $150.00 price tag of a used foot for my little outboard!

I bought this old Mercury 110 9.8 hp a few years back and finally decided to try and get it running. I fired it up this weekend and found out it wasn’t pumping water so I decided to take the foot off to replace the impeller and while I was at it I figured it would be a good time to try and fix the big gapping hole that was in the foot.

There was a hole a little smaller than what is shown here and a crack just to the left of the main hole. I used my dremel tool to clean out the crack and the main hole and clean the paint away from anywhere the JB Weld would contact the aluminum casting

From what I have read about JB weld it works best when it glues to materials together in a surface to surface contact. With that in mind I carved out a piece of aluminum angle that would fit inside the hole and also have ears on either side that can be glued to the main casting.

Once I had it fitted in like I wanted I mixed about a teaspoon full of JB Weld. I applied a thin layer to the inside of the foot where the aluminum angle goes and also applied a thin layer to the ears of the aluminum angle and some on the bottom…basically everywhere it touched the aluminum casting. I pressed in the formed aluminum angle and started glopping on the rest of the JB weld to fill all the cracks and gaps.

JB weld is not super runny, but it is thin enough to slowly ooze out of the big holes and cracks I was trying to fill. I fought with it for about 10 minutes thinking it would thicken up and start staying put on its on, but that wasn’t the case. I finally went inside a grabbed a piece of aluminum foil in hopes it would act as sort of a casting form. It worked very well. I just stuck it to the JB Weld I had spread around and was actually able to form it somewhat to the shape of the casting I was repairing.

After the epoxy cured for 6 hours I went out and removed the foil only to find a small air pocket had formed. Not a really big deal, but if figured I would add a little JB weld to that hole too so It wouldn’t look bad…or worse…I know it looks bad, but I am not too concerned about that.

And here it is…I know it is ugly, but it is solid. I think it will work just fine. I’ll update this post in a few months or so and let everyone know if it is still holding up.

I ended up donating this old outboard to the local boy scout troop. It seemed to hold up fine for several years, however I am unsure of the status to date.

outboard motor foot repair
jb weld
mercury 110
cracked alluminum

Category: Miscellaneous Projects