Surge Brakes Free Backing?

DaveJ50

Seaman
Joined
Apr 3, 2006
Messages
71
I just purchased an aluminum boat on a trailer with drum surge brakes. Winter forces me to put the boat away with a 2500lb 35hp 4x4 diesel mower by pulling up my driveway, turning a tight turn at the top, running downhill a little and then backing into the garage.

When backing, the boat just feels a little heaver than I expected and I find myself wondering if the surge brakes are really "free backing" and just how free is free backing.

There is no solenoid but there is a manual cap to turn to lockout the brakes but after stopping on the downhill run the whole mess is compressed enough that the lockout won't engage. There is also a little key I can insert but I would have to insert it before starting downhill for the same reason. I really haven't had the nerve to try it without the brakes enabled and don't think I will.

Is there any way other than cramming my outboard into the garage wall, setting the brake and jacking the trailer to spin a tire backwards to determine if and how much free backing it really is?


Thanks
 

Fl_Richard

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Jan 21, 2005
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1,428
Re: Surge Brakes Free Backing?

If the surge actuator is "compressed" when you turn the lockout the pressure in the brake lines from the original "compression" of the system wil continue to put pressure on the brake rotors as you move it around.

Free backing should be almost as easy as driving forward. The disc brakes will always drag a bit (there nature) but backing should be as easy as forward movement.

Just make sure there is no pressure on ball when you flip the valve and it should be OK.

Good luck and happy boating!
 

jeeperman

Lieutenant Commander
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Aug 2, 2001
Messages
1,513
Re: Surge Brakes Free Backing?

The answer above still applies to drum brakes. Other than when "at rest" the pads should retract a hair from the drum. You have to lock out the brakes when it is "at rest", when level or before you start to push or pull it.
 

SuperNova

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Mar 16, 2007
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Re: Surge Brakes Free Backing?

drum surge brakes.
The way the drum brakes are designed, they are free backing and you shouldn't need to do anything at the coupler to back up. It won't move quite as free as going forward, unfortunately, because the brakes do apply. However, the way they are designed, they can't put any real pressure against the drum, they kind of pivot away from it because of the direction the drum is turning, instead of being forced against the drum as they do when going forward and applying the brakes. If the brakes were truly applying when you were trying to back up, you would have A LOT of difficulty backing up, not just a little.
 

jeeperman

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Re: Surge Brakes Free Backing?

I keep thinking of automotive drum brakes, duh.
 

DaveJ50

Seaman
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Apr 3, 2006
Messages
71
Re: Surge Brakes Free Backing?

Thanks folks.

I checked with the actuator manufacturer yesterday and he said that the braking power would be around 15% in reverse. He also offered to sell me the parts required to install the bypass solenoid and gave me enough info do the install.

I'm going to do just that. The 15% isn't a lot but I have a feeling that I will be able to notice the difference especially on the mower.

The only way I could make the manual lockout work would be to chock the wheels and pull forward before turning the lockout cap. I would have to dismount again to remove the chocks. Even then, the brakes re-activate after any forward pull so this sounds like the way to go.
 

a70eliminator

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Sep 9, 2007
Messages
3,688
Re: Surge Brakes Free Backing?

My surge brakes have the reverse lockout feature, I only have to use it once a year, when I back the boat and trailer up the hill to the barn, backing uphill pushes on the actuator like crazy.
 

Texasmark

Supreme Mariner
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Dec 20, 2005
Messages
14,544
Re: Surge Brakes Free Backing?

I had surge brakes on an 18' boat-trailer that was pretty heavy for the length back in the early '70's. Pulled it with a 400 cu in Chev station wagon which was plenty heavy it'self. Never noticed any difference backing. Towing, when you got on the brakes, there was a slight pause before you felt the weight of the trailer on you, but you could feel the brakes mitigating that load also.

HTH

Mark
 

jeeperman

Lieutenant Commander
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Aug 2, 2001
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Re: Surge Brakes Free Backing?

Thanks folks.
The only way I could make the manual lockout work would be to chock the wheels and pull forward before turning the lockout cap. I would have to dismount again to remove the chocks. Even then, the brakes re-activate after any forward pull so this sounds like the way to go.

Another alternative is using a pin that renders the coupler inactive.
You might have to study yours a bit to determine where a hole is or could be drilled that if you inserted a pin it would prevent the coupler or master cyl. from sliding.
A 1/4" rope from the chocks to the tractor would allow you to yank'em out without getting off.
You will have to have 12volts from tractor to activate the solenoid?
 

DaveJ50

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Messages
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Re: Surge Brakes Free Backing?

Rope isn't a bad idea. I may just use that idea at least until I get my solenoid project done.

I will now slap myself on the forehead for not thinking of that.

My plan for the tractor was to wire a 5 pin cable using only the 5th wire and ground (assuming one of the 5 is a ground) and mount a toggle switch so I could just flip the brakes off before backing.

That plan calls for a 4-5 pin adapter for the trailer side with a pigtail for the solenoid but as of yet I haven't been able to find that exact adapter. I kind of hate to cut all the wires on a new trailer and wire in a new 5 pin plug.

Anyway, that would allow me to plug the tractor or truck into the same adapter and use the lockout on both.
 

SuperNova

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Re: Surge Brakes Free Backing?

Rope isn't a bad idea. I may just use that idea at least until I get my solenoid project done.

I will now slap myself on the forehead for not thinking of that.

My plan for the tractor was to wire a 5 pin cable using only the 5th wire and ground (assuming one of the 5 is a ground) and mount a toggle switch so I could just flip the brakes off before backing.

That plan calls for a 4-5 pin adapter for the trailer side with a pigtail for the solenoid but as of yet I haven't been able to find that exact adapter. I kind of hate to cut all the wires on a new trailer and wire in a new 5 pin plug.

Anyway, that would allow me to plug the tractor or truck into the same adapter and use the lockout on both.
Let me throw another complcation into the works. If you are going to go with the solenoid idea, there something you need to know. There are two styles of solenoid valve. One just blocks the line(deadheads) and the other blocks the line and allows the fluid coming from the master cylinder to be diverted back into the resevoir. I strongly recommend using the one that bypasses the fluid back into the resevoir. There is potential for the one that deadheads to possibly damage the seals in your master cylinder due to pressure buildup. Not always, but the potential is there and if you are going to be installing this from new anyway, why not go with the better design?
 

DaveJ50

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Apr 3, 2006
Messages
71
Re: Surge Brakes Free Backing?

I strongly recommend using the one that bypasses the fluid back into the resevoir.

I didn't know about the seals blowing but I wanted the bypass type so it wouldn't lock the brakes where they are just from stopping down hill.

He said that when I flip the switch the fluid should all return to the master cylinder and the moving portion will slide all the way back. That means that there will be no more brakes until I flip the switch and out run the trailer for a foot or 2 to pull the inner member back out.

That shouldn't be a problem since I can push the whole mess +15% braking backwards but it still sounds a little scary.
 

jeffnick

Senior Chief Petty Officer
Joined
May 24, 2004
Messages
695
Re: Surge Brakes Free Backing?

This is what I use for getting the trailer into tight places:
IMG_2419.jpg
 
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