Thanks Dave,
I have managed to get a picture of the 'plans' off Google but they are not too wonderful are they!
I am thinking that a cut and paste replacement of the rotten parts will be required, but as I would not even class myself as a carpenter let alone a model maker I can see exciting times ahead! The black bits on my boat are really black, and spongy. I will pm you as I think I am going to need all the help I can get.

Chris

Hi Chris
Sounds like it was an IC model. That black stuff is ply impregnated with nitro fuel. I have a copy of the original plan but it was intended more as a building guide for the pre-cut parts.
All Aerokits followed the same basic design and had a ply keel running the entire length of the keel. Vertical formers attached to the keel were skinned with thin plysheets. The oil usually seeps down along the keel from the inside and causes the ply to delaminate. You can usually get away with removing just the damaged parts and replacing with new ply wood. if you can do that and fill any dents etc with plastic padding followed by a covering and Eze-Kote it should be solid and watertight.
I am attaching some pics of a hull I acquired for the 48" Crash Tender in a part (badly) built state. The last pic is of my Sea Queen hull after stripping for comparison. You can clearly see how the gunge can get into the wood grain especially if it was not treated with Eze-Cote inside.
I have many more pics of various Aerokits restorations so if you would like copies I will share via Dropbox. Just send me a pm with your email and I will send you the link (it's all free)
Dave

Thanks Dave,
I applied my Black and Decker mouse detail sander to the hull, using only the weight of the sander. Turns out it has been epoxy coated, I have removed sufficient paint to see what is underneath it and there are 2 small areas where the wood is black and nasty. One consists of a few spots about half way between the bow and the stern, and mid way between the keel and the joint with the side skin, and the other is a line about 3 inches long and quarter inch wide running alongside the keel. The keel also seems to be poor on that side as well. What I really would like is a copy of the plans, so that I can see what I am dealing with. Nothing on E Bay! At the moment anyway.

Chris

If it's old chances are it has oil based paints and will need lots of elbow grease, paint strippers and if it's anything like my Sea Queen some careful use of a hot air stripper to get the final residue out of the wood.
I did start with Flash oven cleaner but changed to Nitromors and a scraper.
It will be a ply hull and if it had an ic engine fitted you will need to strip out much of the inside to get rid of any diesel impregnated wood. I would also consider replacing the prop shaft and re-positioning to a less acute angle as you will not need the height in the boat that an ic required. IC used prop shafts often have little or no bearing left and can also be badly bent or twisted.
Eze-Kote was very popular to protect the engine bay in a model plane and I still have a bottle bought some 20 years ago. it will protect the wood but I suspect you will need some form of tissue or cloth to make the hull waterproof. Others seem to prefer this to lay-up resin but I have not seen any pictures posted to prove its suitability.
Good luck and perhaps you will consider a build blog so others can see how you progress?
Dave