Proper Use of Sealant

I'm a little confused as to the best application of 5200 verses 4200 sealant. Which is best for sealing engine mounting bolts? Is one better than the other when used below water line? Which is stronger if you are attaching an object to aluminum or fiberglass and using as a glue and no fasteners? I have read the product information from the manufacturer but would appreciate real world, experience based application results.Thanks in advance for any replies.

Re: Proper Use of Sealant

Both are very good sealants, I think the question you need to ask yourself is do I ever want to get whatever you are installing off. If not then go with the 5200 it is permanent stuff that is very hard to remove. Drain tubes, gluing applications would be better served with the 5200. I personally went the 4200 on my motor mounting bolts just incase I need to make adj. in height or whatever. I wanted to be abel to get the bolts back out. Whichever you use make sure to clean the area well with acetone before application. Also if you are only doing a small job get the smaller squeeze tube instead of the cartridge type. None of it likes to keep real well and for what they get for it hate to have half a tube go hard. I'm sure alot of others will respond with their preferences as well..

Re: Proper Use of Sealant

the post above pretty well covers it. The 5200 could take 10 days to cure, 4200 a lot quicker, but both tough stuff..and true about once its an open tube, it starts to cure. It will keep longer if stuck in the fridge, but after a bit of time, its no good anymore

Re: Proper Use of Sealant

I appreciate both replies. If you should ever try to remove either sealant from the boat, is there a chemical that will soften it? Thanks for the information.

Re: Proper Use of Sealant

Yes - de-bond (or anti-bond) 2015 comonly available on many marine websites and stores. Spray it on and use very thin pinao wire to "saw" through the sealant, works good.