Sealing outboard mounting bolts

[realslimshady]

May seem like a 'derrr' question, but I'm working with a blank canvas here and most of my experience is with outdrives/inboards.
Going to hang a 90 hp outboard on the back of my Marina 21 project, the two lower mounting bolts are well below the waterline. Is there an accepted
established recognised (quick thumb thru thesaurus ) method of sealing these bolts?

 

[RobWales]

Sikaflex...not sure which number sorry, but that's what I've used on all of mine in the past,and plenty of it too....

 

[aquapower]

May seem like a 'derrr' question, but I'm working with a blank canvas here and most of my experience is with outdrives/inboards.
Going to hang a 90 hp outboard on the back of my Marina 21 project, the two lower mounting bolts are well below the waterline. Is there an accepted
established recognised (quick thumb thru thesaurus ) method of sealing these bolts?

I sealed mine with silicone sealer and had no problems, you can use sikaflex but remember you might want to remove at some point.

 

[realslimshady]

so we're saying, 'fit with plenty of sealant of your choice'...
can do that!

 

[jfm]

Skiflex 291 and 3M's 3200 are nice polyurethane sealants but also adhesives, as Aquapower says. Don't use 292 or 3M's 5200 because those are like welding. White silicone is much easier to remove later and will work perfectly well. So imho:

If the boat is on chocks or a trailer, use silicone
If it's permanently in the water, maybe use the 291/3200

 

[Chris_robb_ndota]

Skiflex 291 and 3M's 3200 are nice polyurethane sealants but also adhesives, as Aquapower says. Don't use 292 or 3M's 5200 because those are like welding. White silicone is much easier to remove later and will work perfectly well. So imho:

If the boat is on chocks or a trailer, use silicone
If it's permanently in the water, maybe use the 291/3200

Couldn't have summed it up better than this really.

 

[realslimshady]

Thanks chaps, appreciate it.