# Sealing transom screws in aluminium



## wolfenstein (Jan 6, 2014)

I'm putting a new finder in an aluminum tracker. The current one has a few clips screwed in the hull to hold it in place. Just wondering what I should use to seal those screws in. Don't want something permanent in case I change again in the future. Thanks.


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## Snakecharmer (Apr 9, 2008)

I'd use a silicon caulk.


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## BuckeyeFishin07 (Apr 10, 2017)

3m 5200 is what I used to mount mine on my tracker.


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## Southernsaug (May 23, 2019)

BuckeyeFishin07 said:


> 3m 5200 is what I used to mount mine on my tracker.


Absolutely, this is what you want. Used it putting a second fish finder/GPS on my Aluminum tracker and it's still solid and dry. Just shoot some in the hole and run your screw in make sure it squeezes out around the head


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## fastwater (Apr 1, 2014)

X's 3 on the 3m 5200.


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## Ranger6 (Dec 27, 2015)

If you want the ability to remove these screws easier, if needed, I would use the use the 3m 4200. The 5200 is more permanent.


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## wolfenstein (Jan 6, 2014)

Thanks guys. Just ordered some 5200


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## DiverDux (May 19, 2012)

wolfenstein said:


> Thanks guys. Just ordered some 5200


I am going to preface this post by saying that I have no horse in the race and I won't lose any sleep over what you do, but...
You will regret taking this advice. 3M 5200 is a permanent bedding agent and should never be used if there is the slightest posibility that you will have to remove or take apart the object you are bonding with 5200. The truth is that there are very few applications where 5200 is recommended. You would be better served with 3M 4200 or 3M 4000 UV as a bedding agent. But, you do as you wish, just remember this post when you need to remove those screws! 

Need more... 
Watch this video. Watch the whole thing, but the 2:13 mark is pertinent to this thread.


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## wolfenstein (Jan 6, 2014)

They had what seemed like regular silicone. Not planning on changing it up for a long time. But I did see another video of the 5200 pulling a wooden table apart. Maybe a bit stronger than I want.


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## bridgeman (Aug 26, 2010)

Don't sweat using the 5200, I've removed a number of screws and bolts that were seated in it. No issues at all.


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## privateer (Apr 26, 2012)

I removed the transducers from my fiberglass boat a number of years ago. 30' Baha Cruiser that sits in water 6-months of year. the 5200 used to seal them essentially made threads and i had to unscrew the transducers. They were in good too. I had to use a pipe wrench, a 3' extension pipe, and even then had to brace my feet on the trailer cross members to unscrew the things. Then to clean out to fiberglass, i had to use a dremel grinder. Not complaining, just saying it is darn good for underwater use. I used 5200 to put the new ones in too...

That said, i am not going to use 5200 on my trailered Alumacraft that i am putting new transducer on. I plan to use BoatLife Life Caulk. This is the same stuff i use on all my above waterline on the Baha. I further plan to put two of the plastic mounting plates on the hull and then screw the transducers to these. This will give easy adjustments where i will not have to make new holes in the hull. bolt the plates and seal, then just screw the transducers to the plate. Since this boat goes in/out of the water, dealing with a small leak is not an issue as it is with the big boat in the water.

one other thing to consider. i have found that both 5200 and 4200 will yellow over time. The BoatLife stuff has not yellowed. and comes in white, black, and clear...


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## bowhunter1487 (Aug 13, 2014)

Trailer boat, get any old silicone caulk and it will be fine.

Docking it, epoxy a mounting bracket don't even tempt fate.


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## bustedrod (May 13, 2015)

been using flex seal for years on my boat , works real nice lol


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## Bluefinn (Jan 26, 2007)

bustedrod said:


> been using flex seal for years on my boat , works real nice lol


I replaced my transom last year with 5200 on my aluminum. The transducer holes still leaked & I was able get it all off. I had to put an aluminum backing plate on the inside & redid it with 5200. I think life calk is even stronger.


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## wolfenstein (Jan 6, 2014)

Changed it up, got the 4200. One of the cable ties keeps leaking water after I pulled the screw. 2/3 up transom...no idea where It comes from


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## $diesel$ (Aug 3, 2018)

I've been using silicon for years and i have never had it fail.....just say'n.


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## cincinnati (May 24, 2004)

Drill through & squeeeeze that silicone between fender washers! 😲


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## TRIPLE-J (Sep 18, 2006)

I mount a small piece of 1/2 or 3/4 inch plastic to the transom on my boat...roughly 4 inches tall by however long you can get on there ...and then mount all my add ons to that..that way I'm not putting holes in my transom everytime I want to mount something back there...just screw it into the plastic....if the plastic gets too many holes in it I put a new piece on using the old one as a template and re-use the original mounting holes in my transom for the plastic...
Just saves putting more holes in your transom


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## privateer (Apr 26, 2012)

TRIPLE-J said:


> I mount a small piece of 1/2 or 3/4 inch plastic to the transom on my boat...roughly 4 inches tall by however long you can get on there ...and then mount all my add ons to that..that way I'm not putting holes in my transom everytime I want to mount something back there...just screw it into the plastic....if the plastic gets too many holes in it I put a new piece on using the old one as a template and re-use the original mounting holes in my transom for the plastic...
> Just saves putting more holes in your transom


couple of places sell panels for this. think last one i got was branded from cabelas. think is made from starboard


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## Jim white (Feb 19, 2018)

There's several different brands of that stuff nowadays. It is expensive


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