Welding cylinder block and crankcase

[teded72]

I' ve got a johnson 50hp that has about a 1" hole in the block side(still have the piece that broke out) and a starlike crack on crankcase. Local outboard repair guy said it could be welded. Is this wise? I just don't want to spend money on a rebuild kit and then weld goes. Any leads on a used cylinder block and crankcase, if the weld thing is a bad idea? Model#50ESL75B Any info would be much appreciated.

 

[JasonAych]

Re: Welding cylinder block and crankcase

Welding aluminum is tricky, especially keeping it non-porous. All depends on how talented the welder is. If done right it should work.

I assume this is from the engine freezing?? If so, you may have internal damage as well.

I'd consider looking for another block .

 

[JasonAych]

Re: Welding cylinder block and crankcase

Also, if not tig welded, you may end up with other cracks that may no be apparent right away.

 

[bktheking]

Re: Welding cylinder block and crankcase

Depends on where it broken as well, broke a rod did ya?

If it's high up on the cylinder where the piston rides good luck getting a smooth surface for the ring to ride on, if it's low enough it might work, again depends on where it broke, you might be better off finding a powerhead.

 

[teded72]

Re: Welding cylinder block and crankcase

All the damage is in the lower part of the block. where the crank and rod pass. Called a local welder, said he could weld with a high frequency tig. Said the weld would be no problem and inexpensive. Just wanted to get some advice from boaters rather than a welder. Also, having a hard time finding the "correct" block and crankcase. What years and hp are interchangable? Mine is 50ESL75. Thanks for the help!

 

[Chris1956]

Re: Welding cylinder block and crankcase

I used some Marine-Tex to close up a hole in the block of my old Fat-Fifty Johnny. The repair was permanent. Of course, the hole was in a part of the block that didn't have any stress from the moving parts.

 

[JasonAych]

Re: Welding cylinder block and crankcase

With what you just said, I'd just go for it.

 

[mungo]

Re: Welding cylinder block and crankcase

For what its worth---
After TIG welding aluminium on areas that need a good seal i always smear Loctite wick-in all over the general area. This fills in and seals all porosity.Also when welding make sure the welder earth lead is attached to the block as close to the weld as possible---I`ve seen a few engines ruined due to arcing on bearing surfaces because the earth was incorrectly placed on the part to be welded

 

[bktheking]

Re: Welding cylinder block and crankcase

All the damage is in the lower part of the block. where the crank and rod pass. Called a local welder, said he could weld with a high frequency tig. Said the weld would be no problem and inexpensive. Just wanted to get some advice from boaters rather than a welder. Also, having a hard time finding the "correct" block and crankcase. What years and hp are interchangable? Mine is 50ESL75. Thanks for the help!

You'd get better advice from a welder, if he says he can do it then I'd just pay and get it done, what have you got to lose at this point

 

[kenmyfam]

Re: Welding cylinder block and crankcase

Could most likely be done but you have to stop the crack tendency first by drilling a small hole at the end of the extremes of the cracks. The "star" one could be an issue.
If the welder will warranty his work then go for it. If not thensteer clear.
Just my humble opinion though.

 

[5150abf]

Re: Welding cylinder block and crankcase

I am both a welder and a boater and I wouldnt hesitate to do this on my boat, if done correctly the repair should outlast the engine.