bob's nosecone/low water pickup installation

[reacler]

hey guys, I have a bob's lwpu that I'm installing on a new lower unit. Specifically, a Yamaha 225 Excel. I've done this in the past, but I have issues with cracking/chipping filler and leaking water from the water jacket around the original intake area that's been covered up.

I'm looking for recommendations on what adhesives, and/or gap filler materials to use. Or if it's better to weld it solid, then what to use as filler?

I've always tack welded it to the lower and then used epoxy to fill most of the gap that's created. Then I use some filler to finish it. I've tried long and short strand fiberglass bondo, metal bondo, regular bondo, marine tex, and just more epoxy. It always seems to crack eventuallyyy although some work better than others. I think it's poor adhesion to the aluminum because that's where the failures always seem to be. I don't think it's bad surface preparation, I think it's because of the vibration of the engine.

wasn't sure if this was the right area to post this, but hope you guys can help I dont want to keep redoing it every season or 2

[Merc 2.5]

I've repaired mine with jbweld. (Original) not the 5 min stuff , it usually dont crack

bondo dont work good with water

[mrichartz]

Marine Tex, jbweld

The jbweld kwik weld 5 min will get soft,rubbery if in water.

[reacler]

thanks guys, I'll try the longer cure JBweld. I didn't know that about the 5 minute stuff and water, that's interesting.

[Merc 2.5]

thanks guys, I'll try the longer cure JBweld. I didn't know that about the 5 minute stuff and water, that's interesting.

I found it does good , just takes alot of it and hard to sand, but I guess u cant have ur cake and eat it to

[mrichartz]

It's definitely worth the extra effort sanding to just use just jbweld or Marine Tex..
using filler just makes for the possibility of cracking etc which usually always happens..

[Merc 2.5]

Yes I hear marine tex just as gud. maybe better. Idk