Installing A Replacement Rubrail

Rubrail Replacement Instructions

BY: Ron Tanis, Tanis R & D LLC

List of things to have to complete this job: 

Battery drill (s) 

Caulking gun

100% silicone caulk black (Prefer LifeSeal)

Large flat screwdriver (preferably with very soft, dull edges)

Hot air heat gun

¾” masking tape


Safety Knife & single edged razor blades

Flat Pry-bar

Stainless #10 x 1” (Deck to Hull screws IF needed)

Stainless #10 x 1 1/4” (Base rail to hull screws)


Roll paper towel


TIPS: Chock the wheels to keep the boat stationary

  Removal Procedures of Old Rubrail:

1)      Remove center trim cap at transom & retain

2)      Using a screwdriver or pick tool, pull one of the vinyl insert ends out, grab with your hand & pull out from base rail. The warmer the insert the easier the pulling will be, if very cold prepare to pull pretty hard. Pull entire insert out.

3)      Remove all the screws from the base rail & remove, you may have silicone holding parts of it on, just pull & it will release.

4)      Begin cleaning the hull/deck joint with soap & water, then acetone, Scrape excess silicone off. Inspect caulk in the hull/deck joint (underneath) anywhere it is loose or missing will need to be recaulked. If it looks bad & there are a lot of questionable sections of poor caulk do the following:

5)      RECAULKING STEP: loosen all the hull/deck screws at least a ¼” out. Pry the joint apart with a screwdriver or flat pry-bar, keeping it spread open to remove the old caulk. Take a good safety knife & cut the old caulk out, this may take some time, the cleaner the work the better the new seal will be. Sometimes a single edged razor blade works well to remove all the old caulk.

6)      Use a high quality 100% silicone to recaulk & then tighten the hull/deck screws, if any are striped, simply add a new screw within an inch of the striped one. Use you finger to smooth out the caulk while making sure it is well sealed.

  Installing New Base Rail

1)      Begin by cleaning the deck surface with a rag soaked in acetone (be careful, acetone is VERY FLAMABLE) check all the deck to hull attachment screws are tight and countersunk. Repair as needed if only a few are stripped simply drill / countersink / and insert a new screw (#10 –1” stainless CS)

2)      Next run a band of masking tape around the whole deck just above where the base rail will go. Now mark on the tape a line where each hull/deck fastener is so you will not hit a screw head with the base rail fasteners.

3)      The goal is to have a screw every 4-6” through the hull/deck. You should have a mark on your tape about every 8-12” for each hull/deck screw. DO NOT USE THE PRE-DRILL HOLES IN THE BASE RAIL UNLESS THEY LINE UP WHERE YOU NEED THEM  (they rarely do, plan on drilling/countersinking all the base rail holes)

4)      Next is the base rail, this can be done by yourself or with a friend, I prefer this step by myself. If doing it alone you must have a suitable table to hole the rail for you. Get creative here, a small round table strapped to a creeper works, you want the coil to be flat, and at the same height as the installation level, and you want to be able to “unroll” the coil at your pace. I have also left the coil in the box and pulled it out as needed while on a table kept horizontal at the right elevation.

5)      Your coil “un-rolling” orientation will dictate whether you start to the right or left, just make sure the “lip” of the base rail is “down”. Begin at the center of the transom, pay attention to where the hull/deck screws are & where the center finishing trim cap screws will need to go when finished. Your first screw may be 3-6” away from the center of the transom. From here you simply look at your marks on the tape and “split the difference” pre-drilling a 9/64” hole then countersink the base rail and drive the screw in. This is done all the way around the boat.

6)      Bending the base rail around the corners: Be sure a screw is located  through the base rail  just before the radius begins if there isn’t one there, add one.

7)      I use a commercial grade heat gun on low if warm out, high if cold inside, a blow drier will work as well to heat the base rail. Begin by heating the rail over a 10” section that will make the turn, I heat both the inside & outside, and bottom moving the heat gun all the time, do not pause or you could burn the plastic. When the rail is warm enough it will draw around the corner with little effort,  keep some tension on the “feed” rail but too much tension & too much heat will cause the rail to stretch & deform, best to go slow & easy. If the bottom lip bulges out but the rest of the rail looks good keep going. (will attend to this in a minute) once the rail is pulled all the way around the corner hold it there until cooled, a wet towel will speed this up. Once cooled add a screw just after the turn, stretch out about 5 feet of rail & add screws to the first 12-18”. Now go back to the corner & address the bulged bottom lip if it bulged. With the rail secured you can reheat just the bottom lip & take a smooth large flat screwdriver and press & form the rail into position & let cool.

8)      Now stretch the rail along the deck side & place a screw about every 4-5 feet, stop when near the bow. Now is when you can adjust the rail up & down to get a straight appearance, if happy with the straightness go ahead & begin screwing between your marks on the tape. NOTE: the “tightness” of your screws need to be consistent, over tightening will cause the rail to distort & when done you will see a “rippled” effect when looking down the side of the job, be careful!  Most decks you will maintain the distance between the top of the rail & a radius or style line molded in the deck just above the rail. The bottom lip may or may not be consistent with the hull, that normal.

9)      Repeat the corner bending process when you get to the bow, gets a little trickier, but the procedure is the same, then repeat down the other side & back corner.

10)   Base termination, I always do a rough cut 4-6” beyond where the rail will need to be cut & let it lay on top of the other side & screw the rail up to about 10” from the end point. Now carefully cut the excess rail with a hack saw, or sawzall. NOTE: I always place a piece of ¼” plywood between the rails to prevent any “oops” with the saw. I also make this cut 1/8th “ long then carefully sand down the rest of the way to achieve a perfect fit.



 1)      VERY WARM INSERT IS THE KEY TO SUCCESS  Placing the insert in a black garbage bag & left in bright sunshine for an hour will work, placing in a large cooler filled with 150 deg. Water also works, the temp. needs to be as close to 150 deg. As possible, the insert will be like cooked spaghetti when ready. At the plant we had a large galvanized tub with a couple hot plate electric heaters underneath to warm the water.

2)      While the insert is warming up gather at least one additional set of hands & some leather gloves, the next step needs to move fast before the insert cools, a third set of hands is helpful. I suggest reading this part carefully & mentally going through the steps to avoid any pauses. If  you trip up & miss the opportunity to get it all in before it cools you can peel it out & start over, or warm with your heat gun & keep going at a slower pace.

3)      This is for 3 installers:

Installer with a flat screwdriver with rounded edges, presses the top insert edge down & with other hand pushes in, moving forward at a slow walk pace dragging the screwdriver while pressing down & in.

Helper#1 sets the insert bottom lip into the base rail 10-16” ahead of the installer

Helper #2 unrolls the insert carefully keeping the rail untangles & not allowing any twisting, he feeds helper #1 & stays 2-3 feet ahead of helper #1

4)      When everyone is ready the installer starts with placing the insert 1” longer than needed & begins the process (1” longer allows for shrinkage when cooled) Now start the installation moving quickly around the boat, if done right an Advance will take about 2 minutes. Again when you get to the center of the transom allow extra & cut 2-3” long. Now while cooling take a mallet & tap the insert in all around the boat & will snap in & should fit tight.

5)      Final Trim: With the insert cooled mark & cut both ends so they land flush & tight, I will mark, pull out 4-5” cut, re-warm with heat gun & press back into place. Now place the center trim cap & screw through the insert, and base rail.

6)      Next step is caulking the rail: (ONLY CAULK THE BOTTOM OPEN SEAM) I like to mask the hull & bottom of the rail all the way around to minimize the mess & do a clean neat job. This is the tedious part. Next take you favorite 100% silicone (black) & fill the cavity around the boat working 3-4 feet at a time (a roll around stool is really helpful here) Then take your finger & smooth out the caulk & keep working around the boat. When done carefully peel off the tape & your DONE!!


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