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Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Right Hand - 3,500 lbs
Demco

Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Right Hand - 3,500 lbs

Part Number: 18787
In Stock
$76.98
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Passenger's-side hydraulic trailer brake assembly features a single-plunger design. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern. 1-800-940-8924 to order Demco accessories and parts part number 18787 or order online at etrailer.com. Free expert support on all Demco products. Great prices and Fastest Shipping for Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Right Hand - 3,500 lbs. Accessories and Parts reviews from real customers.
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Demco Accessories and Parts - 18787

  • Trailer Brakes
  • Hydraulic Drum Brakes
  • Brake Assembly
  • Demco
  • 10 x 2-1/4 Inch Drum
  • Single Servo
  • RH
  • 3500 lbs

Passenger's-side hydraulic trailer brake assembly features a single-plunger design. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern.


Features:

  • Marine-grade hydraulic drum brake assembly is great for boat trailers
    • Designed for use with surge-type trailer brake actuators
  • Sturdy, corrosion-resistant steel construction
    • Galvanized backing plate
    • Stainless steel spring hardware
    • Zinc-plated wheel cylinder
  • Single-plunger design delivers 15 - 20 percent braking in reverse
  • Riveted brake shoes provide increased durability
  • Periodic manual adjustment required
  • Mounting bolts sold separately
  • Made in the USA


Specs:

  • Configuration: right hand (passenger's side)
  • Dimensions: 10" diameter x 2-1/4" thick
  • Mounting flange bolt pattern: 4 on 4"
  • Wheel size: 13" - 15"
  • Axle rating: up to 3,500 lbs
  • 1-Year warranty


SB18787M Demco Galvanized 10" Marine Trailer Brake Assembly - Single Servo - Right Hand




California residents: click here


Customer Satisfaction Score:

Ratings & Reviews

4.8

43 reviews
Passenger's-side hydraulic trailer brake assembly features a single-plunger design. Galvanized steel resists rust, making the assembly great for boat trailers. Mounting flange has 4-bolt pattern.

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Works well.



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Great product and fit perfect Great service and will order again!



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At my door today quick ship great communication have not installed yet but don't anticipate any issuses



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Quick and easy assembly with all the information needed



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Perfect fit. Works great. I wish I had known it didn't come with nuts and bolts. Other than that it was perfect.



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Perfect fit. Bolt on and go??



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Nice quality product. Easy to install... Well, as easy as any brake job could be. Spend a little bit and buy new bolts when you do this job.



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Easy to install and fast shipping.



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"great product low price" quote is valid. bolted right up. Note: I have a boat, and the only thing missing on the backing plate is the half inch hole for my water flush out that was on my old ones, had to drill one next to the flange mount. I packed a little extra grease in the calipers too.



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brakes hubs and bearings arrived very fast.all parts fit perfect.sales person was excellent in helping me with the boat trailer parts.thank you



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Like the assembly being galvanized to last longer and already assembled. Being labeled for left and right is a nice added touch, but not necessary with single piston cylinders. I added a flush kit to my trailer and had to drill a hole through the plate to add, not a problem.



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So happy i found etrailer. They had the quality parts i had been looking for at a great price. I am equally happy with the speedy free shipping. I recieved the brake assemblies and installed them in less time than it took to locate them. Thank you. You will be my go to trailer parts supplier for all future parts. I have 5 different trailers and am sure i will require your services.
Robert K.



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Great products. Easy cross referencing from old to new replacement. Great info video.



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Put new brakes, drums, bearings and seals and hubs on boat trailer found all parts here and received really fast always order parts for trailers here and always will



by:

Afternoon job for both left and right side of 2000 Jayco pop up camper.
Cheaper and easier than break job.

Fast shipping.



by:

Perfect fit. Just with it came with nuts and bolts.



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Put new brakes,drums, bearings and seals and hubs on boat trailer found all parts here and received really fast always order parts for trailers here and always will



by:

When I realized my brakes were in need of repair and no local shop worked on trailer brakes I decided to do it myself.
With the help of the etrailer folks I had a new set of brakes and was ready for another fishing season.
Great products, they do what they say and great customer support.



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These worked great. Much easier to replace the whole assembly like this, than replacing all of the original rusted out components. These are galvanized, so they should last a long time. I'm using these for a boat trailer for a 21 foot fiberglass euro styled V8 powered pleasure boat that weighs about 3000 pounds.



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So happy i found etrailer. They had the quality parts i had been looking for at a great price. I am equally happy with the speedy free shipping. I recieved the brake assemblies and installed them in less time than it took to locate them. Thank you. You will be my go to trailer parts supplier for all future parts. I have 5 different trailers and am sure i will require your services.
Robert K.



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After going to numerous trailer stores and auto part stores in my home town I called Bill at etrailer. I found Bill to be very professional and helpful.. The package was ordered on Monday afternoon and was on my door step on Wednesday afternoon. The item was exactly what I had ordered. I will continue to purchase my trailer needs from Bill.



by:

Wheel came off boat trailer, must have bent backing plate. New huds rubbed and would not turn. Got new plates from etrailer fit perfect. Got here fast and easy to install.



by:

Good price and bolted up perfect! Etrailer.com has great prices and fast shipping when you need your parts fast. This is the 3rd complete trailer rebuild and I wouldn't think about buying from any other supplier.

Bobby M. Maryland


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See what our Experts say about this Demco Accessories and Parts

  • Troubleshooting Surge Brakes Locking up When in Reverse
    With surge brakes, you have a brake actuator applying the needed pressure to the brakes but to be able to back up you will need to have a manual lockout or an electric lockout solenoid, like # T4748800, which will close when you shift the vehicle into reverse, allowing the trailer to be backed up. You may also need a solenoid cover like the Titan # T4835800183, depending on what brake actuator you currently have. Typically surge brakes are found on boat trailers, and commonly the trailer...
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  • Solution to Allow Trailer with Surge Brakes to Back Up
    You can install free-backing brake assemblies that won't activate when the trailer is backed up or you can install a lockout on the actuator. I attached a link to a page that has all of the free-backing assemblies we carry for you to check out. You'd need to measure the dimensions you currently have and then match the size you need by selecting it from the filters on the page. I'd need to know what brand of surge actuator you have to pick out the correct lock out you'd need.
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  • How To Activate Surge Brakes on Triple Axle To Verify Brakes Are All Working Properly
    There are 2 ways to activate a surge brake actuator. This is going to require you to have 2 people if you are wanting to then spin the tires to ensure the brakes are working correctly. I have linked a help article near the bottom of the page which goes into further detail and will help you visually see since there are images. The first way involves using a flat head screwdriver to manually push the master cylinder rod and send pressure to the brakes. Not all actuators have the ability...
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  • What Causes a Trailer With Surge Brakes To Lockup While In Reverse
    The issue your friend is having with his trailer is a mechanical one so we can rule the vehicle out. The reasoning for this is because the only way you would have been able to back up the trailer with using just a 4-way trailer connector is if you either physically applied a manual lockout or the trailer had free backing braking assemblies. Surely you would know whether or not the manual lockout was used or not so that leads me to think you have free backing braking assemblies. The free...
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  • Solution for Surge Trailer Brakes that Activate When Backing Trailer Up
    Surge brakes will activate when backing the trailer up unless you do one of two things to address the problem. You can install free-backing brake assemblies on the trailer (I attached a link to a page that has all of the ones we carry) or you can use a reverse lockout solenoid which will prevent hydraulic pressure from making it to the wheel cylinders when the reverse light circuit activates the solenoid. If you have a Titan actuator you would need the part # T4748800 or if you have...
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  • Troubleshooting Surge Brake Actuator that Won't Release Brakes
    Sounds like your trailer has an electric reverse lockout which prevents the brakes of your trailer from applying so that you can back the trailer up. If now the brakes won't release after the issue you had with someone else backing up the trailer that sounds like a mechanical problem. Possible something has bent inside the surge actuator which won't allow the inner piece to slide forward and release the brake pressure. You should inspect the coupler looking for any damaged or bent components...
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  • Troubleshooting Trailer Surge Brakes That Activate in Reverse with New Truck
    A surge coupler/actuator will activate the brakes on the trailer unless it has a lockout feature, either a manual lockout as with coupler # T63FR or an electric lockout as on part # T4854020. Since the same trailer backs up without any problem using your other truck, the 2012 F-150, most likely that truck has a reverse light circuit present on the trailer wiring to deliver a lockout signal for the coupler's solenoid. If your new truck has only a 4-pole wiring setup then you'll just need...
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  • Removing Surge Coupler-Actuated Brakes from Mc Clain Boat Trailer
    If you want to deactivate the hydraulic brakes on your boat trailer, you can certainly do so. The simplest way to do this would be to drain the brake fluid from the lines by disconnecting the brake lines from the wheel cylinders and allowing the fluid to drain. You'd then immobilize the articulating portion of the coupler by drilling holes in either side and sliding a bolt through to prevent the coupler from compressing. A better long term option would be to remove the coupler and replace...
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  • How to Know When a Trailer Coupler Shock is Bad
    If your trailer wants to slam forward and back as you apply the brakes of your tow vehicle the shock is bad and needs to be replaced. When a shock goes bad it no longer dampens the movement of the actuator which causes what I described. If the shock you have can easily be extended and retracted then it needs to be replaced. I attached a page that has all of the replacement shocks we offer.
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  • Trailer Surge Coupler Can be Pushed in By Hand and Brakes are Weak
    The coupler should be very difficult to push in by hand but it doesn't return on its own. There is likely a problem inside your coupler that will need to be addressed to get it working properly again. It is most likely the shock that is inside. There are replacement shocks but I would need to know the manufacturer and model of the coupler you have. I have included a link to the shocks we carry. If you can't find a part number or manufacturer on the coupler then you may be able to find...
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  • Determining if Replacement Shock is Needed for Brake Actuator
    A shock like the Replacement Shock # T1242600 for Titan Model 6 and 10 Brake Actuators is essentially designed to dampen the movement of the actuator. There are a couple things you can do to see if a replacement is in order. First, if you find that your trailer is slamming forward and back as you apply the brakes in your tow vehicle, this is an indication that the shock has gone bad. Also see if the shock can easily be extended and retracted without any resistance. This would also indicate...
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  • Troubleshooting Trailer Brakes Locking Up When Driving Forward
    Unless the trailer became completely unattached from your tow vehicle causing the breakaway pin to be pulled out, forgetting to lock the coupler to the hitch ball, while certainly something you want to double check the next time you tow, would not have caused the trailer brakes to engage during travel. The brakes locking up when going forward was likely caused by some kind of short in the trailer wiring. I recommend inspecting the brake output wire on the trailer for any exposed portions...
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  • How To Check if Trailer Surge Brakes Are Working Properly On Tandem Axle Boat Trailer
    Checking the brakes can be done in two ways. The easiest way is to raise one side of the trailer and spin the wheels while someone applies the surge brakes at the coupler. The better way would be to remove each of the wheels and brake drums and activate the brakes while making sure the wheel cylinders and brake assemblies are functioning properly. After this the first thing I would do is bleed the brakes using the trailers surge coupler to force the fluid from the brake lines and make...
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  • Correct Replacement for Atwood 159-80770 Braking Assemblies
    Yes, the Demco Hydraulic Drum Brake Assembly part # 18788 for left and part # 18787 for right will work well to replace the Atwood 159-80770 Braking Assemblies. They are both 10" x 2-1/4" with a 5 bolt flange so there will be no compatibility issues.
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  • I Want to Replace All of the Surge Brake Equipment on a 2002 Performance Boat Trailer
    The surge brake equipment of your trailer consists of the brake lines, drum brakes and the brake actuator. To ensure I recommend the correct parts for your trailer I will need a little more information. A brake line kit is pretty universal. For a single axle trailer, I recommend using part # T4829900. This kit comes with all of the lines and fittings you will need to replace everything from the actuator to the brake assemblies. For an actuator, I would need to know what type of actuator...
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  • Troubleshooting Reverse Light Fuse Blowing and Reverse Lockout Solenoid Wiring getting Hot
    It sounds like the problem is in the wiring of your reverse lockout solenoid. Most likely the circuit is shorting out somewhere and is causing the circuit to over-draw which is why the fuse is popping and the wire is getting hot. I would inspect the wiring of the circuit and see if you can find any obvious signs of a short and fix as necessary. Cut or exposed wiring or corrosion can cause shorts. I attached an FAQ on trailer wiring for you to check out also.
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  • Troubleshooting 2012 Glastron Boat Trailer With Catching/Slipping Brakes When Moving After Stop
    With your boat trailer, you will have a brake actuating surge coupler. This means that when you brake the hitch ball will pressurize the plunger of your master cylinder applying hydraulic pressure to your brakes. Once stopped the internal shock like # T1242600 should release that pressure and it should allow pulling again without a catch. Since you are feeling a slip or catch, it is likely that shock is not returning correctly to the pulling position. This is likely the issue if there...
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  • Troubleshooting Surge Trailer Brakes that Make Hammering Sound When Applied
    I bet it's a worn out suspension component that's flexing as the trailer pushes into the surge brake actuator and once the brake applies it pulls itself back and repeats the process quickly causing the hammering sound you are experiencing. Check out the suspension of the trailer to see if you can find any worn components that would cause this and fix as needed.
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  • Electric Reverse Lockout On Boat Trailer Surge Coupler is Not Working
    On a trailer that has a surge coupler, if the trailer does not have a manual or electric reverse lockout or free-backing brakes then the brakes will engage when backing up. Free-backing brakes are only available in drum brake applications. So you would have to have a coupler that has either a manual or electric reverse lockout feature. It sounds like you have an electric lockout. An electric lockout will be at the back of the master cylinder. It will be grounded to the trailer frame...
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  • How to Determine if Trailer Brakes are Require for a Boat Trailer
    That is going to depend on a few things. You will need to check with your local DOT to see what the requirements are for trailer brakes. You will need to know the weight of your trailer as well. Depending on the weight of your trailer will also affect how many brake axles are required. I attached a couple help articles on adding brakes to a trailer for you to check out as well.
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  • Recommended Surge Brake Solenoid for Backing Up Boat Trailer
    If you have the single servo brakes like the Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Right Hand - 3,500 lbs # 18787, then you should have the free backing. However if you have an odd angle that can impact the backing up so I do recommend adding the solenoid with the electric connection to your vehicle's reverse light circuit to keep your brakes from engaging. I recommend using the Replacement Solenoid Valve for Titan Brake Actuators with Reverse Lockouts...
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  • Disc Trailer Brakes are Weak on One Side After Replacing Calipers and Pads and Bleeding Brakes
    Like you said, you don't want the trailer wheels to lock up all the time. They should stop the wheels proportionally to how much force is exerted on the actuator. With that said it could be that you are not physically pushing in the actuator all the way to reach lock up. There could also be a leak somewhere but I think you would notice fluid dripping out. Sometimes the brake lines are not large enough depending on how far the actuator is from the calipers. A larger diameter brake line...
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  • Replacing The Hydraulic Brake Assemblies On A 1984 Shorelander Trailer
    We do carry brakes assemblies that will replace yours. It sounds like the brakes you have now are made by Atwood. They no longer make these and have not for quite some time. What we have to replace them are the Demco # 18787 and # 18788. Fortunately we are dealing with a standard size here with the 10" x 2-1/4". You will be able to easily swap these out and get back on the road.
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  • How to Find Surge Coupler, Wheel Cylinders and Bearings for 1997 Eagle Double Axle Boat Trailer
    For the actuator, you'd want to choose one compatible with drum brakes with sufficient capacity for the weight of your trailer. You'd also need to choose between a bolt-on or a weld-on application, the trailer ball size and the lock-out desired (none, manual or electric). You can see our selection by clicking the provided link. The wheel cylinder is a likely place to check for leaks, but if the trailer's been sitting for awhile, you might be better off replacing the brake assemblies,...
    view full answer...
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