Brakes...so much for state inspections

[steved]

I bought this little 5vr last fall... brakes have been less than strong since we got it out this spring. I've literally been running with my controller almost full on to get any comfy stopping power out of it... when I bought it last fall, I could easily slide the wheels when I applied the brakes manually. So that got me thinking...



I just had the wheels off it last month for new bearings, brakes and magnets were good. I checked the adjustment, everything looked good (keep in mind it only had 150 miles on it since I brought it home). And it had just been through inspection (once before I got it, and once again this spring). I also replaced the half-worn-through trailer-to-truck wiring at that time with a new one... everything was soldered.



I remembered there being a ton of scotch-locs under it on the brakes, and I hate them with a passion... they tend to corrode and they sometimes don't fully contact the wires. So I decide today to start redoing the brake wiring. It has been spliced several times, so I simply bought new wire. When done, I will have four splices that will all be soldered.



I start following the routing of the wiring, paying particular attention to that which follows through the axles, and find that one brake was never hooked up. Not damaged, just never hooked up! I've been stopping with THREE brakes!



I have EIGHT connections using scotch-locs, of which all of them are exhibiting signs of corrosion. I do some resistance testing of those connectors... I have SIGNIFICANT resistance from the trailer to the brakes, no wonder I've lost significant braking power.



And to boot, the wiring was practically falling from the frame...



Now my question is, and I think I know the answer, are the magnets polarized? Do they have a positive and negative lead, or are they non-polarized? I don't think they are, or the wires would be well marked...

 

[HBarlow]

No, polarity should not be a concern. When 12v is applied the magnets will be activated.



If more owners checked the brakes and brake wiring on older trailers as you have they would find the same thing. Manufacturers often route wiring to the opposite side brakes by running a wire through one or both of the axles. Chafing occurs over time and the wire shorts. A common problem.

 

[steved]

Well, one thing turns into another, turns into another, and turns into another...

I ended up redoing a bunch of electric work... soldering connections instead of wire nuts, as well as getting the brakes done.

Everything works well, I'm getting battery voltage at the wheels when I pull the break-away switch. I also found several connections were corroded, which were probably causing the issue.

 

[AClayton]

HBarlow is right..... wait until you see the manufacturer's that use nylon wire ties to secure the wires to the axle tube for the opposite wheel brake. It lasts about a month before they come into my shop looking for repairs.



Alan

 

[steved]

I looked at the wires going through the axle tubes... wish ALL the wire was that grade... This wire not only has the common PVC insulation, but it also has a really tough plastic/teflon liner that was next to impossible to strip.



I inspected the access points, which had rubber grommets and the wire appeared fine. I also checked with a meter (to ground) to see if there might be a short, it checked fine.



If I needed to run new wire, I'd probably fish it through the axle tube... better protected there.



As for the tie wraps... that is what was used to attach the feedline to the frame... and they were definitely factory installed. I replaced with plastic wire holders, that are drilled and screwed to the frame.



The only thing I didn't like is the fact the one stretch of wire from the exterior junction box to the interior junction box is only 14ga... the rest is 10ga or 12ga. It hasn't caused a problem yet, and would be a PITA to fish through a new one.

 

[AClayton]

14ga. is good for 15A's in res/com. bldg. codes but stranded 14 used in wiring on trailers will handle 20% more ampacity safely and will not overheat if the insulation is in good shape. The Break-A-Away box is proof of that... . some of those things come with 16ga. wire for the switch. Although,I'm aware it is only used in an emergency situation. Anyway,from what I remember about your trailer from previous posts,it is only about 24 feet long and I doubt the small section of 14ga. will offer you any trouble. Not to hi-jack,but where is Shoemakerville?My family and I are going to invest in big-oil this weekend and take the MH up to Old Millstream in Lancaster,PA.



Alan

 

[steved]

Shoemakersville is north of Reading on I78... if you visit the Cabelas Store, you'll be within 5 minutes of my house... although I will most likely be on my way to Florida (I'll wave!).

 

[jelag]

Remember that electric trailer brakes have star wheel adjusters and need to be adjusted on a regular basis... .



Since these shoes do not self adjust we adjust the brakes each spring when we take the wheels apart and check the bearings...



When ever we come across a connection we don't care for we us a non insulated butt connector and some shrink tube... the key is that the shrink tube we use has an adhesive in the tube and when its heated to shrink it, the adhesive melts and makes a water proof connection... line the shrink tube used in water well applications...



We've had problems with the wires running through the axles... so we have pulled them out, and have tied the wires to the sides of the axles with nylon ties... .



Hope this helps. .