Thru-Hull Fittings

9% off

Groco Combo XL Thru-Hull

$39.73 - $116.68

$39.73 - $116.68

1
9% off

Groco ASC Series Slotted Hull Strainer

$190.95 - $1,523.48

$171.91 - $1,523.48

0
9% off

Groco HSTH Series Combo High Speed Pickup Thru-Hull Fitting with Nut

$22.52 - $1,119.77

$22.52 - $1,119.77
45% off

Whitecap Straight Thru-Hull with Barb

$7.33 - $9.00

$4.38 - $9.00

1
46% off

Whitecap Plastic Mushroom Head Thru-Hull Fitting with SS Flange

$18.13 - $41.08

$14.45 - $41.08

0
16% off

Whitecap 316 Stainless Steel Thru Hull

$57.30 - $146.40

$57.30 - $122.21

0
9% off

Groco TH Series Thru-Hull Lock Nut

$6.23 - $447.47

$6.23 - $447.47

0
18% off

Apollo Conbraco 65-Series Bronze Thru-Hull Flanged Retainer Nut

$4.01 - $27.60

$3.28 - $23.55

0

About Thru-Hull Fittings

Thru Hull Fittings & Tools

Defender Marine offers a full line of thru hull fittings fabricated in a variety of materials. From ½ inch up to 5 inches, our boat thru hulls are the key to successfully rigging any type of intake/discharge pump above or below the waterline. Washdowns, circulating pumps and even saltwater cooled engines depend on the correct size boat thru hull, strainer, valve, and reinforced hose system. Strainers in several shapes, as well as tools to facilitate thru hull installation, are also available at Defender Marine.

What's the best way to install a marine thru hull fitting?

Remember that old adage - slow and steady wins the race? Well, there is no location on a boat to be more careful and slower than installing thru hulls below the waterline. First things first - haul your boat and let it settle, especially if it has a wooden hull. Next, get all of your details straight before you dig out that hole saw! Match pipe thread, determine if your job needs a seacock, fabricate and fit a backing plate and confirm that your metals are compatible to avoid electrolysis. Finally, make certain that all adhesives and sealants have cured prior to going back to the water!

The trials and tribulations of boat thru hulls and strainers.

Isn't it great when an overheated pump turns out to be a clogged or blocked strainer instead of an issue that requires a mechanic and all of his tools? Marine thru hull systems offers several layers of protection for your intake and the expensive mechanical equipment beyond. Strainers and thru hulls with strainer systems from Defender come in several shapes sizes and keep large debris from entering through the hull.

This thru hull fitting is made of what?

Defender offers thru hull fittings made of just about anything. There are several items to consider when choosing your boat thru hull. The most important is the strength of your fitting; in some applications, a seacock or backing plate may strengthen your project. The next is electrolysis. When it comes to boats, electrolysis is part of life, but boat thru hull fittings are normally located under the waterline where metals react more severely. Be certain metals are compatible or use plastic or Marelon thru hull fittings - these are guaranteed not to pit!

Thru-Hull Fittings

Groco Combo XL Thru-Hull

Groco ASC Series Slotted Hull Strainer

Groco HSTH Series Combo High Speed Pickup Thru-Hull Fitting with Nut

Whitecap Straight Thru-Hull with Barb

Whitecap Plastic Mushroom Head Thru-Hull Fitting with SS Flange

Whitecap 316 Stainless Steel Thru Hull

Groco TH Series Thru-Hull Lock Nut

Apollo Conbraco 65-Series Bronze Thru-Hull Flanged Retainer Nut

About Thru-Hull Fittings

Thru Hull Fittings & Tools

What's the best way to install a marine thru hull fitting?

The trials and tribulations of boat thru hulls and strainers.

This thru hull fitting is made of what?

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