How to repair a leaking boat?

How to repair hole in fiberglass boat?

• I have a 16ft fiberglass bass boat and recently hit a stump at a lake and ripped a pretty bad gash in the rear of the hull and part of the bottom of the transom. I am not sure exactly how thick my hull is but the damage area is approximately 3in by 12in and protrudes into the inside of the hull. The part that is leaking water is not this big, I can't even put my finger through the hull but the resin and glass is really beat up and cracked. I do have insurance but really can't afford the deductible right now. I have the supplies to repair it myself but choosing my strategy is the problem. I have removed the fuel tank for a closer look and concluded that it is nearly impossible to reinforce or repair from the inside. Evidently the impact upset the outer layer on the inside of the boat and it is purging up and will not lay down. Also the majority of the internal damage is under the plywood that the fuel tank lays on(which i don't want to remove because it is fiberglassed in).However, I have sanded down the clear coat down to the resin on the outside and am planning to patch over the hull with about 3 layers of bondo fiberglass mat and polyester resin.(I do realize this will cause a decent size lump in the outer hull and I am okay with that.) What I am concerned with is if this will be a good, sturdy way to repair the hull. I am open to and appreciate any suggestions Thanks, Caleb T

• Answer:

  Clean affected area with soap and water insuring anything that could cause contamination is removed. Otherwise, you'll sand contaminantes into hull and repair will delaminate over time. 1)fair edges of damage, two inches back from area 2)fill area in question with foam "little at a time" insuring it's sole purpose", making backing for repair is fullfilled. DO NOT try to force more foam than you absolutely need since "hydraulic pressure will delaminate interior of hull". 3)sand back foam evenly as possible. 4)mix "talcom powder" with fiberglass resin to "peanut butter" consistency 5)apply mixure over foam base to obtain even surface 6)apply 1 piece of matting over foam filler mixture to cover hole and provide foundation for following layers of material (insure matting only covers hole 7)cut several pieces of cloth, one larger than other until you feel comfortable, only a slight raise in surface shall occur. Secret to avoiding lump is too insure surrounding section of repair, two inches back is scarfed 12 to one. (meaning, multiply thickness of hull by 12 and that is how far back bevel shall go). 8)while still wet, apply as many layers of cloth are required until slight lump above surface is present. 9)let dry, then sand smooth and apply whatever coating is compatable with product you used. Good luck, believe "West Systems" web page has a section on how to repair fiberglass boats.