Driving Screws into the transom?

[jfmagana]

I was installing a new washdown pump today and it made me nervous to be driving screws into the wood where the pump is mounted. My question is: is that wood actually the transom or is there an additional piece of plywood before the transom?

Also, I put a dab of 4200 on my screws before driving them in...is that a good or bad idea?

 

[BobP]

If you first drilled through fiberglass then into wood, yes it is the transom. As long as the screws were not too long, you did it the right way.

Next time, also smear the holes besides the the screw threads where ever you do something similar.

 

[Hookup1]

Transom

The transom is plywood cored - sandwiched in fiberglass. It is EXTREMLY important to completly seal any holes you make into or through the coring - especially if they are below the waterline or in a wet part of the bilge.

If that plywood should get wet it will turn to peat moss, loose its strength and cause the transom to fail. It more likley to intrude where there is some pressure - below the waterline, water churned up behind the boat, etc.

All it takes is some 4200 or 5200 in the holes, seal the fresh exposed wood, coat the screws & washers and tighten it up.

 

[seasick]

4200 prefered. It is likely that at some time you will need to remove the pump

 

[gradyfish22]

4200 is good, but 5200 is better, and contray to what many say 5200 can be removed we only use 5200 in the boats we build, no 4200 and we remove stuff all the time, you need to spray acetone on the 5200 and it will work apart with a little effort. Any time a screw going into a bulkhead or into any wood comes loose, add some 4200 to reseal it, as the boat gets older screws may rattle loose over time, and it is possible that a screw hole can be missed from time to time, after all boats have thousands of fasteners and ones bound to be overlooked.

 

[Brad1]

You would use 4200 for this application. According to 3m, while 5200 has additional adhesive strength over 4200, 4200 and 5200 have the same sealant properties. Only use 5200 when a chemical bond is required.

 

[NOTHING ELSE MATTERS]

You would use 4200 for this application. According to 3m, while 5200 has additional adhesive strength over 4200, 4200 and 5200 have the same sealant properties. Only use 5200 when a chemical bond is required.

Ditto.