1987 Lund Predator Transom Rebuild

[fishinnut]

Got started on the transom rebuild today. The 60 hp outboard is hanging from an engine hoist. Removed the end caps and transom cap which was cracked in half. Poked my finger thru three different sections on the transom. Got to work using a 1/2 drill bit about 12 inches long. My ice fishing spud bar worked great for separating the wood from the aluminum skins. Took my son and I about 4 1/2 hrs. to completely remove all the wood. Inside of skins don't look bad at all. Minor corrosion that a little sanding should clean up. Decided that a pourable transom is the way to go as there are too many obstructions, rivets and tow eyes that would be impossible to remove/replace. The rep from Seacast was very helpful and answered all my questions. My biggest concern was how to seal the bottom of the transom, inside skin only goes down about 15 inches and then it is open. He said to use rolled up fiberglass mat and at least three layers of duct tape because of the heat generated. Two layers of tape won't hold. I have a small openning between the inner skin and the side of the boat that's about 1/8 inch that needs to be filled also. Thought silicone would work there but I'll have to ask if Seacast is compatible and won't eat thru the silicone. Took numerous pics and will post later.

 

[DaveInGA]

Sounds good, can you post some pics of the work as you go so we can see how you're doing and how the seacast works?

 

[fishinnut]

Decided that Seacast wasn't the way to go. To much of a problem to seal bottom of transom cavity. Went with marine plywood. Got lucky and found a lumber yard that sells 2x8 sheets. I needed 1/2 and 3/4 for a 1 1/4 transom. No one has 5/8 marine. So buying 1/2 sheet of each saved me some dough. Made my first template using cardboard and then transferred that to 1/2 inch foam board. After minor trimming I then traced the outline onto the plywood which was glued and screwed together. It's now drying. Next vstep cutting it out and waterproofing. Leaning towards nmerous coats of Thompson's waterseal but haven't decided yet. CPES was an option but not sure it's worth the $80 pricetag. Last transom wasn't treated and it lasted 25+ years!!

 

[lckstckn2smknbrls]

On the less expensive side is Spar Urethane on the high end is Epoxy Resin.

 

[fishinnut]

It's done!!! Solid as the day I bought it. Marine plywood glued and screwed together then several coats of Thompsons waterseal. Fit nice and tight in the transom cavity. All bolts replaced and coated with 5200. Had to re-rivet gunnels, transom cap. Probably over 100 rivets in all. Can't wait to give it a test run..

 

[lckstckn2smknbrls]

Pictures.

 

[fishinnut]

Picture showing deflection of transom. Notice gap where engine transom bracket meets transom.

 

[fishinnut]

Cracked transom cap.

 

[fishinnut]

Rotten transom core.

 

[fishinnut]

More rot.

 

[fishinnut]

Transom cavity after rotten wood was removed.

 

[fishinnut]

This mulch was 80% of the transom. Don't know how it held the 60hp and 8 hp kicker. Lund makes good boats!!



Had to remove gunnels on both sides to remove tow eyes. Foam also needed to be removed and then replaced with Great Stuff.

 

[fishinnut]

Made a cardboard template of transom and transferred to the 1/2 inch foam board. Checked fit and trimmed as needed.

 

[fishinnut]

After glueing together 1/2 in and 3/4 in marine plywood the foam template was used to draw transom on plywood. Cut out shape with power saws, treated with numerous coats of Thompsons.