This is Part 2 of our series on How to Install Underwater Boat Lights, to continue to Part 3, click here. Or, if you need help picking a mounting location for the underwater lights, you can go back to Part 1, click here.

In Part 2 we walk you through how to drill through gel coat when wiring LED lights on a boat. During the video, we teach you about best practices for safely drilling through the gel coat on your boat as we prepare to install a set of Liquid Lumens Mavericks Underwater Boat Lights on a Supra SL550. If you want to skip ahead to one of the key steps in the process, here are the timestamps for the step-by-step:

0:41 – Step 1: Start drilling in reverse to begin the hole.

1:06 – Step 2: Finish drilling in forward.

2:08 – Step 3: Feed the wire(s) into the boat and test fit the light.

2:25 – Step 4: Visually align the light and check for issues.

3:00 – Step 5: Drill the first mounting hole.

3:42 – Step 6: If you used tape, remove it now.

3:47 – Step 7: Partially install a screw while maintaining back pressure.

4:13 – Step 8: While positioning the light, drill the second hole.

4:26 – Step 9: Partially install the second screw while maintaining back pressure on the drill.

4:30 – Step 10: Drill the remaining mounting holes.

4:54 – Step 11: Partially install the remaining screws.

4:57 – Step 12: Check final position of the light housing.

Congrats, you’re done drilling holes in your boat! Probably not nearly as scary as a lot of us thought it would be the first time we did it, right? Continue to How to Install Underwater LED Boat Lights Part 3: How to Use 3M Marine Adhesive Sealant to Install Boat Lighting for the next step in your install. Additional Underwater Light Installation Instructions are available here.

Comments and questions are always welcome. Let us know how your own installation went and if there is any other content you’d like to see us share in the future. Thanks for watching!

Transcription of Video

A couple of things to consider when drilling gelcoat.  It is very fragile and does not like drill bits.  If you drill in the forward position it will chip away at your gelcoat.  You may end up with a crack that could run out from the screw hole off the side of the light and have a damaged boat.  So, there are a few tricks that you can do to avoid letting your gelcoat crack.  

One is using some tape in the area that you’re going to drill.  We’ve put down some high temperature masking tape that we use for our powder coat process here.  You can also use blue painter’s tape or even just some basic masking tape.  

STEP 1:  Drill in Reverse to Start

We’re going to put the drill into the reverse drill position.   So instead of drilling forward, we’re going to drill backwards as we break through the outer color layer of the gelcoat.  By doing that, it will allow us to get through the outer color layer and avoid chipping.  Once we’re into the fiberglass, then we’ll put the drill into forward and finish the hole.  

STEP 2:  Finish Drilling in Forward

As you can see, we’re well into the fiberglass now, we’re through the gelcoat so we can put the drill into forward and drill right through.  Now we’ve got a nice pilot hole.  We still want to avoid letting this other hole that’s pre-existing let the drill bit wander.  Normally, we could move from here right up into the 3/8” size.  We’re going to step up a couple of drill sizes just so we can keep the hole centered where we want it and make it all the way through.

So, as we step up in drill size anytime, we need to repeat the process.  We’re going to drill in reverse at first and then we’ll switch it to forward, avoiding any cracks in the gelcoat.  Now we’re ready for our final drill size – 3/8”.    

We’ve got two nice holes, obviously this hole is plenty big to handle whatever we need.  The other wire should fit nicely here.  We’re going to test that now.  Before we drill any of the screw holes, we want to feed the two wires into the boat, position the light, make sure everything looks good.

STEP 3:  Feed Wire(s) into Boat

We’ve got our first Mavericks light here, we’ve unbundled the wire, we’re going to feed it into the boat.

STEP 4:  Visually Align the Light and Check for Issues

You can see with the position we’ve selected we like how the lights position on the boat and where it’s sitting.  We’re running into one problem.  This surf exhaust is getting in the way of our drill getting a nice clean 90 degree angle into the gelcoat, so rather than trying to drill on an angle or cause a problem, we’re going to run over to the hardware store and snag a 90 degree angle drill head so we can have the proper tools for this install that is a little bit unique.  

STEP 5:  Drill the First Mounting Hole

We’ve got our 90 degree angle drill head that we snagged at the hardware store and I’m using a friend here to help me position the light just the way we need it.  He’s got it visually lined up the way that it gives us about the same clearance on one side as the other.  We’ve put tape underneath this very first corner screw hole and we’re going to follow the same process as drilling the wire hole.  We’re going to put the drill bit in reverse.  We’re actually going to use  the light housing as the drill template now because it will align the screw straight into the gelcoat.  We’ll drill in reverse to start and then all the way through.  

Use one hand to give back resistance so as you break through the fiberglass you don’t run your drill into the light housing and put a scratch in your paint. This isn’t our final mounting.  We’re just going to secure that first hole in position for drilling the other hole so we can more easily secure the light.  

STEP 6:  If You Used Tape, Remove it Now

So move it out of the way for just a second.  We’ll get this masking tape off.  

STEP 7:  Partially Install a Screw While Maintaining Back Pressure

We don’t need to go all the way in.  We’re just going to get it set far enough into the gelcoat that it will secure the light for us to pivot and position the other holes.  

Gelcoat and fiberglass are incredibly strong.  We drill that hole just slightly undersized so that you have good purchase into the material with these mounting screw holes, so be sure to maintain good back pressure on the drill as you’re going in, otherwise you’ll end up stripping the heads on your screws.  

STEP 8:  While Positioning the Light, Drill the Second Hole

We’ve got one screw started into the gelcoat to help us with the pivot and now, again I’m going to start drilling in reverse and prep us a hole for the second screw.  

STEP 9:  Partially Install the Second Screw While Maintaining Back Pressure

Now I don’t need a friend.  I’ve got two screws set.  I’m just going to drill the last two holes.  

STEP 10:  Drill the Remaining Mounting Holes

We’ll set a couple of screws in them.  Make sure everything aligns then we’ll pull all four screws out, clean the housing, put our Marine Grade sealant on it then put it all back together.

STEP 11:  Partially Install the Remaining Screws

STEP 12:  Check Final Position of Light Housing

The housing is where we want it.  Everything is lined up nice.  We’re going to pop the screws out, clean it up, put the sealant on it and put it back together the final time.

Continue to Part 3

The post How to Install Underwater LED Boat Lights Part 2: How to Drill Through Gel Coat appeared first on Liquid Lumens.

This is Part 1 of our series on How to Install Underwater Boat Lights, to continue to Part 2, click here.

In Part 1 we cover how to pick the best mounting location for LED Underwater Lights on your boat during installation. During the video, we look at various Liquid Lumens products and where they would work best on this Supra SL550. After reviewing a few different products and mounting locations, we go into detail with selecting the best mounting location for a set of Liquid Lumens Mavericks Underwater Lights. If you want to skip ahead to one of the key steps in the process, here are the timestamps for the step-by-step:

1:31 – Step 1: Look for a location about 1/3 of the way in from each side of the boat if possible.

1:47 – Step 2: Select a flat surface.

1:51 – Step 3: Be sure lights will not interfere with the boat’s equipment.

2:10 – Step 4: Remove any necessary items or panels to gain access to the bilge.

2:27 – Step 5: Inspect the interior area of the boat before you drill.

2:55 – Step 6: Use a reference point to verify where the drill will break into the bilge.

3:50 – Step 7: Cut out drill template and tape to mounting location.

Now you are ready to begin drilling! Continue to How to Install Underwater LED Boat Lights Part 2: How to Drill Through Gel Coat When Wiring LED Lights on a Boat for more help with your installation, or visit our Installation Instructions page for detailed a step-by-step guide. Comments and questions are always welcome. Let us know how we did and what other content you’d like us to see from us in the future. Thanks for watching!

Transcription of Video

Hi, I’m Rob with Liquid Lumens and today we’re going to teach you how to pick the best mounting location for a set of underwater lights on your boat.  We’re going to evaluate a few of our different products.  The Surfrider model light here is representative of the same size and dimensions as our Skinny Dip light, just different components and a different lens.  And the Pipeline here is applicable to either the Pipeline Single color lights that we sell, as well as the RGBW configuration.  The footprint of these two products is actually the same.  They are both right around 4 1/2” in diameter.   As you can see the height and thickness of the housing is varied between the two products.  The thicker housing in the Pipeline, the RGBW allows us to project a little tighter beam angle lens and get you a brighter candela rating off of the light.

As you can see, we’ve removed the factory lights.  We’re going to have to drill some new holes for the bolt hole pattern on our product.  If you’re replacing some factory lights, you’re going to want to reuse as many holes as you can or cover up the old existing holes.  By checking our Surfrider model light or the Pipeline light, we’re able to see that we can cover the whole bolt pattern of the factory light on this boat.  There’s a paper drill template that would come with your set of lights.  We wouldn’t be able to reuse either screw hole in this case, but we can at least cover up the factory pattern so you would never know the factory lights were there.

Let’s walk through a couple of other options if we had a clean boat with no factory lights on it.  In some boats, in the past, we’ve seen customers try to mount their lights out here on the hips of the boat.  

STEP 1:  Look for Location One-third of the Way in from Each Side of the Boat

We prefer to mount about a third of the way in from each side if there is real estate available.  That leaves us this area here.  We have a little bit of a seam in the gelcoat here, so we would likely mount here or here.  

STEP 2:  Select a Flat Surface

We don’t want to go too low because as the surf tabs are actuating and coming up, we don’t want them to risk bumping into the light or blocking light and creating a shadow in the water.  

STEP 3:  Be Sure Lights Will Not Interfere with the Boat’s Equipment

If we can go a little bit higher, about here, we’d be able to clear this surf tab or here.  Other lights, like our Mavericks light, we’ve seen them mounted both here and also vertically here.  

Inside the back of the Supra SL, there’s a surf locker and you can see inside the locker there is a plastic panel to help drain water out of the interior of the boat.  

STEP 4:  Remove Any Access Panels to Gain Access to the Bilge

We’re going to remove that panel so we can see the inside of the transom area of the gelcoat where we need to drill holes.  

STEP 5:  Inspect the Interior of the Boat Before You Drill

Here’s a little bracket that had some wire and tubing zip tied onto the back of it.  We’ve already snipped the zip tie and we’re going to move it out of the way and zip tie it over here to these other hoses in the engine compartment while we’re drilling holes just to make sure we’re clear of anything and we won’t damage any of these items inside the boat.

If we look along the back wall, you can see that one tube and that one wire harness are the only two items back here that we’re concerned about.  It’s a pretty clean open space in the Supra.  One thing we always like to do in picking a mounting location is find an object in the back of the boat that you can reference  on the exterior.  In most cases, that’s going to be the exhaust port.  We can see the exhaust port down there with the clamps on it.  By measuring where we intend to mount the light on the exterior of the boat in reference to that flange on the exhaust port or one of the bolts we can then come and measure in the interior of the boat and verify that we see where that hole is going to come through so we don’t drill into something we don’t want to.  

STEP 6:  Use a Reference Point to Verify Where the Drill will Break into the Bilge

This is more or less the mounting location we have selected for the light.  By referencing the flange on the exhaust port we can see, we’ll call it an inch and a quarter between the bottom of the light and the screw.  We know that none of our drill holes are going to be lower than an inch and a half off of this bolt on the flange here, so if we measure an inch and a half up from that in the interior, verify there’s nothing there that we’re worried about, we should be good to start drilling holes.

STEP 7:  Cut Out Drill Template and Tape to Mounting Location

We’ve prepped the exterior of the boat, we’ve prepped the interior of the boat, we know we’re good to drill.  We’ve now cut out our drill template that was provided with the installation kit and we are going to pick our best mounting location here.  We clearly want to reuse this hole because it’s a big hole and it’s going to be right in the vicinity if we’re able to.  The wire hole locations on this drill template are here and here.  We’ve measured them and they are just about one and three-quarter inches apart.  We got lucky because on this Supra, as you can see, if we go to one and three-quarter inches we’ll actually be able to drill out this hole a little bigger for one of the wires on the Mavericks and the other wire is going to fit into the existing hole that was already on the boat.

A couple of things to keep in mind when you attach the drill template to the boat.  First of all, never use a level when checking the position of the drill template on your boat because the boat may not be level on the trailer and the trailer may not be on level ground.  This is more of a visual alignment or you can measure off of other reference points on the boat to make sure the lights are equally spaced and equally level to the position you want them in.  Now we have the template positioned where we intended to drill, but we’ve run into one issue, so we want to explain some things that you need to look out for.  It looked good where we could reuse the interior mounting hole from the factory light, and we have this large opening behind where this hole is going to go, so we were going to go with those two holes, however, we can see that there’s a little bit of a radius and a curvature on the back of the boat right here that we’re going to be butting up against.  What we want to avoid is, if the light is butting up against that radius, it’s going to lift it off the boat just a hair and prevent us from getting a good, water-tight seal on that upper edge of the light.  So, we’re going to offset it down just a hair.  We’ll end up moving this hole down just a little bit, but we’re going to be drilling a bigger hole here than what exists so we’ll end up consuming that hole anyway in the process and it should be just fine.

Continue to Part 2 – How to Drill Through Gel Coat

The post How to Install Underwater LED Boat Lights Part 1: Where to Mount LED Underwater Lights on Boats appeared first on Liquid Lumens.